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  • How do I check if a process is running from c++ code ?

    - by Maciek
    Hey all, I'm writing a C++ app that will communicate with another process via boost::interprocess, however I need to check if the other process is actually running first - as the other process is responsible for creating the inter-process shared memory. How do I check if the other process is running ? folks, I'm specifically required to check other processes

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  • How to use Bonjour?

    - by Roman
    First, what exactly Bonjour does (pleas read my guesses written bellow)? Here I found out that Bonjour enables automatic discovery of computers, devices, and services on IP networks. But I thought that it not only "discovers devices on IP network" it also creates an IP network by assigning IP addresses to devices where Bonjour is running. Am I right? And I still miss the essence. Does it work in the following way? First I connect devices (for example laptops) physically so that they potentially can communicate with each other. Then, let say, on some laptops I have Bonjour running and then, as a consequence, these laptops assign IP addresses to them self in automatic way. So, laptops (where Bonjour is running) build an IP network. Does it work in this way? Or may be a computer running Bonjour is not considered as a service and it does not broadcast itself just because Bonjour is running on this computer. I mean that the applications running on the computers need to use Bonjour to broadcast themself. So, it is applications that broadcast themself (not computers) and it is not done automatically (application needs to broadcast themself explicitly). Is it right? How exactly my application can broadcast itself? Can I use command line to register an service (so that all applications using Bonjour knows that a new service appeared)? Further, I would like to have an application which use the IP network created by Bonjour. For that my application needs to know which devices/services are present in the network. In more details, my application needs to have a list of services. Each service in the list should have a name, the IP address where it is running and the port which is used by the application. Can Bonjour provide this information in some way? If it is the case, how exactly it works. How my program can get this information from Bonjour? Can my program read some file created by Bonjour and containing the above mentioned information? Can I use some commands in command line to retrieve this information? I have a special interest in accessing the information about services from files, environment variables or commands in command line. These options seems to me to be the simplest! Since in these case I do not need to use any additional libraries to communicate with Bonjour from a particular programming language. P.S. Pleas ask questions if something is not clear in my question. I will try to formulate my question in a more clear way. P.P.S. I use Windows 7. ADDED: I plan to write my applications in PHP. Every computer should run a Apache web server. And I want to use Bonjour to help computer discover each other (computers are working in a local network).

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  • PPTP connection fails with errors 800/806

    - by Mark S. Rasmussen
    I've got a client (Server 2008 R2) that won't connect to our production environment PPTP VPN server (Server 2003, running RRAS). The server is behind a firewall that has TCP1723 open as well as GRE. Other clients at our office are able to connect just fine. Our office is behind a Juniper SSG5-Serial firewall, but all outgoing traffic is allowed, and multiple other clients are able to connect to VPN servers without issues. I've also setup a completely different VPN server on another network outside of our office. The functioning clients connect just fine - the Server 2008 R2 machine doesn't. Thus it's definitely a problem with this machine in particular. I've rebooted it. I've disabled the firewall, no dice on either. I've run PPTPSRV and PPTPCLNT on the server/client and they're able to communicate perfectly - indicating there's no problem using neither TCP1723 nor GRE. The Server 2008 R2 machine is also running as a VPN server itself (incoming connection) and that's working perfectly. We have the issues no matter if there are active incoming connections or not. I'm not sure what my next debugging step would be; any suggestions? EDIT: The event log on the server has the following warning from RasMan: A connection between the VPN server and the VPN client xxx.xxx.xxx.xxx has been established, but the VPN connection cannot be completed. The most common cause for this is that a firewall or router between the VPN server and the VPN client is not configured to allow Generic Routing Encapsulation (GRE) packets (protocol 47). Verify that the firewalls and routers between your VPN server and the Internet allow GRE packets. Make sure the firewalls and routers on the user's network are also configured to allow GRE packets. If the problem persists, have the user contact the Internet service provider (ISP) to determine whether the ISP might be blocking GRE packets. Obviously this points to GRE being a potential problem. But seeing as I have other clients connectiong without problems, as well as PPTPSRV and PPTPCLNT being able to communicate, I'm suspecting this might be a red herring. EDIT: Here are the anonymized events logged by the client in chronological order: CoId={742CB15C-A7E0-47B7-8240-0EFA1139CBD9}: The user XXX\YYY has started dialing a VPN connection using a per-user connection profile named ZZZ. The connection settings are: Dial-in User = XXX\YYY VpnStrategy = PPTP DataEncryption = Require PrerequisiteEntry = AutoLogon = No UseRasCredentials = Yes Authentication Type = CHAP/MS-CHAPv2 Ipv4DefaultGateway = No Ipv4AddressAssignment = By Server Ipv4DNSServerAssignment = By Server Ipv6DefaultGateway = Yes Ipv6AddressAssignment = By Server Ipv6DNSServerAssignment = By Server IpDnsFlags = Register primary domain suffix IpNBTEnabled = Yes UseFlags = Private Connection ConnectOnWinlogon = No. CoId={742CB15C-A7E0-47B7-8240-0EFA1139CBD9}: The user XXX\YYY is trying to establish a link to the Remote Access Server for the connection named ZZZ using the following device: Server address/Phone Number = XXX.YYY.ZZZ.KKK Device = WAN Miniport (PPTP) Port = VPN3-4 MediaType = VPN. CoId={742CB15C-A7E0-47B7-8240-0EFA1139CBD9}: The user XXX\YYY has successfully established a link to the Remote Access Server using the following device: Server address/Phone Number = XXX.YYY.ZZZ.KKK Device = WAN Miniport (PPTP) Port = VPN3-4 MediaType = VPN. CoId={742CB15C-A7E0-47B7-8240-0EFA1139CBD9}: The link to the Remote Access Server has been established by user XXX\YYY. CoId={742CB15C-A7E0-47B7-8240-0EFA1139CBD9}: The user XXX\YYY dialed a connection named ZZZ which has failed. The error code returned on failure is 806. Running Wireshark on the client shows it trying and retrying to send a "71 Configuration Request" While the server shows the incoming client requests, but apparently without replying: Given that this is GRE traffic, I think rules out the GRE traffic being blocked. Question is, why doesn't the server reply? This is the Configuration Request the server receives from the non functioning client (meaning no response is sent to the client request): And this is the Configuration Request the server receives from the working client: To me they seem identical, except for differing keys and magic numbers, and the fact that one client receives a response while the other doesn't.

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  • udp through nat

    - by youllknow
    Hi everyone! I've two private networks (each of them behind a typical dsl router). The routers are connected to the WWW. The extern interface of each router have one dynamic IP address. I want to stream data via UDP directly between one client in private network A and one client in private network B. I've already tried a lot of things (see: http://en.wikipedia.org/wiki/UDP_hole_punching, or STUN). But it wasn't possible for me to transfer data between the two clients. It's possible to use a server (located in the WWW, with static IP) to transfer the extern IPs (and extern ports) from the routers between the clients. So imagine client A knows client B's external IP and client B's external port assigned by his router. I simply tried sending UDP packet to the receivers external IP/port combination, but without any result. So does anyone know what do to communicate via UDP throw the two NAT routers? It must be possible??? Or does Skype, for example, not directly communicate between the clients when the call eachother (voice over ip). I am sorry for my bad English! If something is confusing don't mind asking me!!! Thanks for your help in advance. ::::EDIT:::: I can't get pwnat or chownat working. I tried it with my own dsl-gateway - didn't work. Then I set up a complete virtual environment using VMWare. C1 (Client 1, WinXP Prof SP3): 172.16.16.100/24, GW 172.16.16.1 C2 (Client 2, WinXP Prof SP3): 10.0.0.100/24, GW 10.0.0.1 C3 (Client 3, WinXP Prof SP3): 3.0.0.2/24, GW 3.0.0.1 S1 (Ubuntu 10.04 x64 Server): eth0: 172.16.16.1/24, eth1: 1.0.0.2/24 GW 1.0.0.1 S2 (Ubuntu 10.04 x64 Server): eth0: 10.0.0.1/24, eth1: 2.0.0.2/24 GW 2.0.0.1 S3 (Ubuntu 10.04 x64 Server): eth0: 1.0.0.1/24, eth1: 2.0.0.1/24, eth2: 3.0.0.1/24 +--+ +--+ +--+ +--+ +--+ |C1|-----|S1|-----|S3|-----|S2|-----|C2| +--+ +--+ +--+ +--+ +--+ | +--+ |C3| +--+ Server S1 and S2 provide NAT functionality. (they have routing enabled and provide a firewall, which allows trafic from the internal net and provide the nat functionality) Server S3 has routing enabled. The client firewalls are turned off. C1 and C2 are able to ping C3, e.g. visit C3's webserver. They are also able to send UDP Packets to C3 (C3 successful receives them)! C1 and C2 have also webservers running for test reasons. I run ""chownat -s 80 2.0.0.2"" at C1, and ""chownat -c 8000 1.0.0.2"" at C2. Then I tried to access the Webpage from C1 via webbrower localhost at port 8000. It didn't work. Can anybody help me? Any suggestions? If you have any questions to my question, please ask!

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  • [GEEK SCHOOL] Network Security 4: Windows Firewall: Your System’s Best Defense

    - by Ciprian Rusen
    If you have your computer connected to a network, or directly to your Internet connection, then having a firewall is an absolute necessity. In this lesson we will discuss the Windows Firewall – one of the best security features available in Windows! The Windows Firewall made its debut in Windows XP. Prior to that, Windows system needed to rely on third-party solutions or dedicated hardware to protect them from network-based attacks. Over the years, Microsoft has done a great job with it and it is one of the best firewalls you will ever find for Windows operating systems. Seriously, it is so good that some commercial vendors have decided to piggyback on it! Let’s talk about what you will learn in this lesson. First, you will learn about what the Windows Firewall is, what it does, and how it works. Afterward, you will start to get your hands dirty and edit the list of apps, programs, and features that are allowed to communicate through the Windows Firewall depending on the type of network you are connected to. Moving on from there, you will learn how to add new apps or programs to the list of allowed items and how to remove the apps and programs that you want to block. Last but not least, you will learn how to enable or disable the Windows Firewall, for only one type of networks or for all network connections. By the end of this lesson, you should know enough about the Windows Firewall to use and manage it effectively. What is the Windows Firewall? Windows Firewall is an important security application that’s built into Windows. One of its roles is to block unauthorized access to your computer. The second role is to permit authorized data communications to and from your computer. Windows Firewall does these things with the help of rules and exceptions that are applied both to inbound and outbound traffic. They are applied depending on the type of network you are connected to and the location you have set for it in Windows, when connecting to the network. Based on your choice, the Windows Firewall automatically adjusts the rules and exceptions applied to that network. This makes the Windows Firewall a product that’s silent and easy to use. It bothers you only when it doesn’t have any rules and exceptions for what you are trying to do or what the programs running on your computer are trying to do. If you need a refresher on the concept of network locations, we recommend you to read our How-To Geek School class on Windows Networking. Another benefit of the Windows Firewall is that it is so tightly and nicely integrated into Windows and all its networking features, that some commercial vendors decided to piggyback onto it and use it in their security products. For example, products from companies like Trend Micro or F-Secure no longer provide their proprietary firewall modules but use the Windows Firewall instead. Except for a few wording differences, the Windows Firewall works the same in Windows 7 and Windows 8.x. The only notable difference is that in Windows 8.x you will see the word “app” being used instead of “program”. Where to Find the Windows Firewall By default, the Windows Firewall is turned on and you don’t need to do anything special in order for it work. You will see it displaying some prompts once in a while but they show up so rarely that you might forget that is even working. If you want to access it and configure the way it works, go to the Control Panel, then go to “System and Security” and select “Windows Firewall”. Now you will see the Windows Firewall window where you can get a quick glimpse on whether it is turned on and the type of network you are connected to: private networks or public network. For the network type that you are connected to, you will see additional information like: The state of the Windows Firewall How the Windows Firewall deals with incoming connections The active network When the Windows Firewall will notify you You can easily expand the other section and view the default settings that apply when connecting to networks of that type. If you have installed a third-party security application that also includes a firewall module, chances are that the Windows Firewall has been disabled, in order to avoid performance issues and conflicts between the two security products. If that is the case for your computer or device, you won’t be able to view any information in the Windows Firewall window and you won’t be able to configure the way it works. Instead, you will see a warning that says: “These settings are being managed by vendor application – Application Name”. In the screenshot below you can see an example of how this looks. How to Allow Desktop Applications Through the Windows Firewall Windows Firewall has a very comprehensive set of rules and most Windows programs that you install add their own exceptions to the Windows Firewall so that they receive network and Internet access. This means that you will see prompts from the Windows Firewall on occasion, generally when you install programs that do not add their own exceptions to the Windows Firewall’s list. In a Windows Firewall prompt, you are asked to select the network locations to which you allow access for that program: private networks or public networks. By default, Windows Firewall selects the checkbox that’s appropriate for the network you are currently using. You can decide to allow access for both types of network locations or just to one of them. To apply your setting press “Allow access”. If you want to block network access for that program, press “Cancel” and the program will be set as blocked for both network locations. At this step you should note that only administrators can set exceptions in the Windows Firewall. If you are using a standard account without administrator permissions, the programs that do not comply with the Windows Firewall rules and exceptions are automatically blocked, without any prompts being shown. You should note that in Windows 8.x you will never see any Windows Firewall prompts related to apps from the Windows Store. They are automatically given access to the network and the Internet based on the assumption that you are aware of the permissions they require based on the information displayed by the Windows Store. Windows Firewall rules and exceptions are automatically created for each app that you install from the Windows Store. However, you can easily block access to the network and the Internet for any app, using the instructions in the next section. How to Customize the Rules for Allowed Apps Windows Firewall allows any user with an administrator account to change the list of rules and exceptions applied for apps and desktop programs. In order to do this, first start the Windows Firewall. On the column on the left, click or tap “Allow an app or feature through Windows Firewall” (in Windows 8.x) or “Allow a program or feature through Windows Firewall” (in Windows 7). Now you see the list of apps and programs that are allowed to communicate through the Windows Firewall. At this point, the list is grayed out and you can only view which apps, features, and programs have rules that are enabled in the Windows Firewall.

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  • Another Marketing Conference, part two – the afternoon

    - by Roger Hart
    In my previous post, I’ve covered the morning sessions at AMC2012. Here’s the rest of the write-up. I’ve skipped Charles Nixon’s session which was a blend of funky futurism and professional development advice, but you can see his slides here. I’ve also skipped the Google presentation, as it was a little thin on insight. 6 – Brand ambassadors: Getting universal buy in across the organisation, Vanessa Northam Slides are here This was the strongest enforcement of the idea that brand and campaign values need to be delivered throughout the organization if they’re going to work. Vanessa runs internal communications at e-on, and shared her experience of using internal comms to align an organization and thereby get the most out of a campaign. She views the purpose of internal comms as: “…to help leaders, to communicate the purpose and future of an organization, and support change.” This (and culture) primes front line staff, which creates customer experience and spreads brand. You ensure a whole organization knows what’s going on with both internal and external comms. If everybody is aligned and informed, if everybody can clearly articulate your brand and campaign goals, then you can turn everybody into an advocate. Alignment is a powerful tool for delivering a consistent experience and message. The pathological counter example is the one in which a marketing message goes out, which creates inbound customer contacts that front line contact staff haven’t been briefed to handle. The NatWest campaign was again mentioned in this context. The good example was e-on’s cheaper tariff campaign. Building a groundswell of internal excitement, and even running an internal launch meant everyone could contribute to a good customer experience. They found that meter readers were excited – not a group they’d considered as obvious in providing customer experience. But they were a group that has a lot of face-to-face contact with customers, and often were asked questions they may not have been briefed to answer. Being able to communicate a simple new message made it easier for them, and also let them become a sales and marketing asset to the organization. 7 – Goodbye Internet, Hello Outernet: the rise and rise of augmented reality, Matt Mills I wasn’t going to write this up, because it was essentially a sales demo for Aurasma. But the technology does merit some discussion. Basically, it replaces QR codes with visual recognition, and provides a simple-looking back end for attaching content. It’s quite sexy. But here’s my beef with it: QR codes had a clear visual language – when you saw one you knew what it was and what to do with it. They were clunky, but they had the “getting started” problem solved out of the box once you knew what you were looking at. However, they fail because QR code reading isn’t native to the platform. You needed an app, which meant you needed to know to download one. Consequentially, you can’t use QR codes with and ubiquity, or depend on them. This means marketers, content providers, etc, never pushed them, and they remained and awkward oddity, a minority sport. Aurasma half solves problem two, and re-introduces problem one, making it potentially half as useful as a QR code. It’s free, and you can apparently build it into your own apps. Add to that the likelihood of it becoming native to the platform if it takes off, and it may have legs. I guess we’ll see. 8 – We all need to code, Helen Mayor Great title – good point. If there was anybody in the room who didn’t at least know basic HTML, and if Helen’s presentation inspired them to learn, that’s fantastic. However, this was a half hour sales pitch for a basic coding training course. Beyond advocating coding skills it contained no useful content. Marketers may also like to consider some of these resources if they’re looking to learn code: Code Academy – free interactive tutorials Treehouse – learn web design, web dev, or app dev WebPlatform.org – tutorials and documentation for web tech  11 – Understanding our inner creativity, Margaret Boden This session was the most theoretical and probably least actionable of the day. It also held my attention utterly. Margaret spoke fluently, fascinatingly, without slides, on the subject of types of creativity and how they work. It was splendid. Yes, it raised a wry smile whenever she spoke of “the content of advertisements” and gave an example from 1970s TV ads, but even without the attempt to meet the conference’s theme this would have been thoroughly engaging. There are, Margaret suggested, three types of creativity: Combinatorial creativity The most common form, and consisting of synthesising ideas from existing and familiar concepts and tropes. Exploratory creativity Less common, this involves exploring the limits and quirks of a particular constraint or style. Transformational creativity This is uncommon, and arises from finding a way to do something that the existing rules would hold to be impossible. In essence, this involves breaking one of the constraints that exploratory creativity is composed from. Combinatorial creativity, she suggested, is particularly important for attaching favourable ideas to existing things. As such is it probably worth developing for marketing. Exploratory creativity may then come into play in something like developing and optimising an idea or campaign that now has momentum. Transformational creativity exists at the edges of this exploration. She suggested that products may often be transformational, but that marketing seemed unlikely to in her experience. This made me wonder about Listerine. Crucially, transformational creativity is characterised by there being some element of continuity with the strictures of previous thinking. Once it has happened, there may be  move from a revolutionary instance into an explored style. Again, from a marketing perspective, this seems to chime well with the thinking in Youngme Moon’s book: Different Talking about the birth of Modernism is visual art, Margaret pointed out that transformational creativity has historically risked a backlash, demanding what is essentially an education of the market. This is best accomplished by referring back to the continuities with the past in order to make the new familiar. Thoughts The afternoon is harder to sum up than the morning. It felt less concrete, and was troubled by a short run of poor presentations in the middle. Mainly, I found myself wrestling with the internal comms issue. It’s one of those things that seems astonishingly obvious in hindsight, but any campaign – particularly any large one – is doomed if the people involved can’t believe in it. We’ve run things here that haven’t gone so well, of course we have; who hasn’t? I’m not going to air any laundry, but people not being informed (much less aligned) feels like a common factor. It’s tough though. Managing and anticipating information needs across an organization of any size can’t be easy. Even the simple things like ensuring sales and support departments know what’s in a product release, and what messages go with it are easy to botch. The thing I like about framing this as a brand and campaign advocacy problem is that it makes it likely to get addressed. Better is always sexier than less-worse. Any technical communicator who’s ever felt crowded out by a content strategist or marketing copywriter  knows this – increasing revenue gets a seat at the table far more readily than reducing support costs, even if the financial impact is identical. So that’s it from AMC. The big thought-provokers were social buying behaviour and eliciting behaviour change, and the value of internal communications in ensuring successful campaigns and continuity of customer experience. I’ll be chewing over that for a while, and I’d definitely return next year.      

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  • What's up with LDoms: Part 4 - Virtual Networking Explained

    - by Stefan Hinker
    I'm back from my summer break (and some pressing business that kept me away from this), ready to continue with Oracle VM Server for SPARC ;-) In this article, we'll have a closer look at virtual networking.  Basic connectivity as we've seen it in the first, simple example, is easy enough.  But there are numerous options for the virtual switches and virtual network ports, which we will discuss in more detail now.   In this section, we will concentrate on virtual networking - the capabilities of virtual switches and virtual network ports - only.  Other options involving hardware assignment or redundancy will be covered in separate sections later on. There are two basic components involved in virtual networking for LDoms: Virtual switches and virtual network devices.  The virtual switch should be seen just like a real ethernet switch.  It "runs" in the service domain and moves ethernet packets back and forth.  A virtual network device is plumbed in the guest domain.  It corresponds to a physical network device in the real world.  There, you'd be plugging a cable into the network port, and plug the other end of that cable into a switch.  In the virtual world, you do the same:  You create a virtual network device for your guest and connect it to a virtual switch in a service domain.  The result works just like in the physical world, the network device sends and receives ethernet packets, and the switch does all those things ethernet switches tend to do. If you look at the reference manual of Oracle VM Server for SPARC, there are numerous options for virtual switches and network devices.  Don't be confused, it's rather straight forward, really.  Let's start with the simple case, and work our way to some more sophisticated options later on.  In many cases, you'll want to have several guests that communicate with the outside world on the same ethernet segment.  In the real world, you'd connect each of these systems to the same ethernet switch.  So, let's do the same thing in the virtual world: root@sun # ldm add-vsw net-dev=nxge2 admin-vsw primary root@sun # ldm add-vnet admin-net admin-vsw mars root@sun # ldm add-vnet admin-net admin-vsw venus We've just created a virtual switch called "admin-vsw" and connected it to the physical device nxge2.  In the physical world, we'd have powered up our ethernet switch and installed a cable between it and our big enterprise datacenter switch.  We then created a virtual network interface for each one of the two guest systems "mars" and "venus" and connected both to that virtual switch.  They can now communicate with each other and with any system reachable via nxge2.  If primary were running Solaris 10, communication with the guests would not be possible.  This is different with Solaris 11, please see the Admin Guide for details.  Note that I've given both the vswitch and the vnet devices some sensible names, something I always recommend. Unless told otherwise, the LDoms Manager software will automatically assign MAC addresses to all network elements that need one.  It will also make sure that these MAC addresses are unique and reuse MAC addresses to play nice with all those friendly DHCP servers out there.  However, if we want to do this manually, we can also do that.  (One reason might be firewall rules that work on MAC addresses.)  So let's give mars a manually assigned MAC address: root@sun # ldm set-vnet mac-addr=0:14:4f:f9:c4:13 admin-net mars Within the guest, these virtual network devices have their own device driver.  In Solaris 10, they'd appear as "vnet0".  Solaris 11 would apply it's usual vanity naming scheme.  We can configure these interfaces just like any normal interface, give it an IP-address and configure sophisticated routing rules, just like on bare metal.  In many cases, using Jumbo Frames helps increase throughput performance.  By default, these interfaces will run with the standard ethernet MTU of 1500 bytes.  To change this,  it is usually sufficient to set the desired MTU for the virtual switch.  This will automatically set the same MTU for all vnet devices attached to that switch.  Let's change the MTU size of our admin-vsw from the example above: root@sun # ldm set-vsw mtu=9000 admin-vsw primary Note that that you can set the MTU to any value between 1500 and 16000.  Of course, whatever you set needs to be supported by the physical network, too. Another very common area of network configuration is VLAN tagging. This can be a little confusing - my advise here is to be very clear on what you want, and perhaps draw a little diagram the first few times.  As always, keeping a configuration simple will help avoid errors of all kind.  Nevertheless, VLAN tagging is very usefull to consolidate different networks onto one physical cable.  And as such, this concept needs to be carried over into the virtual world.  Enough of the introduction, here's a little diagram to help in explaining how VLANs work in LDoms: Let's remember that any VLANs not explicitly tagged have the default VLAN ID of 1. In this example, we have a vswitch connected to a physical network that carries untagged traffic (VLAN ID 1) as well as VLANs 11, 22, 33 and 44.  There might also be other VLANs on the wire, but the vswitch will ignore all those packets.  We also have two vnet devices, one for mars and one for venus.  Venus will see traffic from VLANs 33 and 44 only.  For VLAN 44, venus will need to configure a tagged interface "vnet44000".  For VLAN 33, the vswitch will untag all incoming traffic for venus, so that venus will see this as "normal" or untagged ethernet traffic.  This is very useful to simplify guest configuration and also allows venus to perform Jumpstart or AI installations over this network even if the Jumpstart or AI server is connected via VLAN 33.  Mars, on the other hand, has full access to untagged traffic from the outside world, and also to VLANs 11,22 and 33, but not 44.  On the command line, we'd do this like this: root@sun # ldm add-vsw net-dev=nxge2 pvid=1 vid=11,22,33,44 admin-vsw primary root@sun # ldm add-vnet admin-net pvid=1 vid=11,22,33 admin-vsw mars root@sun # ldm add-vnet admin-net pvid=33 vid=44 admin-vsw venus Finally, I'd like to point to a neat little option that will make your live easier in all those cases where configurations tend to change over the live of a guest system.  It's the "id=<somenumber>" option available for both vswitches and vnet devices.  Normally, Solaris in the guest would enumerate network devices sequentially.  However, it has ways of remembering this initial numbering.  This is good in the physical world.  In the virtual world, whenever you unbind (aka power off and disassemble) a guest system, remove and/or add network devices and bind the system again, chances are this numbering will change.  Configuration confusion will follow suit.  To avoid this, nail down the initial numbering by assigning each vnet device it's device-id explicitly: root@sun # ldm add-vnet admin-net id=1 admin-vsw venus Please consult the Admin Guide for details on this, and how to decipher these network ids from Solaris running in the guest. Thanks for reading this far.  Links for further reading are essentially only the Admin Guide and Reference Manual and can be found above.  I hope this is useful and, as always, I welcome any comments.

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  • Thread placement policies on NUMA systems - update

    - by Dave
    In a prior blog entry I noted that Solaris used a "maximum dispersal" placement policy to assign nascent threads to their initial processors. The general idea is that threads should be placed as far away from each other as possible in the resource topology in order to reduce resource contention between concurrently running threads. This policy assumes that resource contention -- pipelines, memory channel contention, destructive interference in the shared caches, etc -- will likely outweigh (a) any potential communication benefits we might achieve by packing our threads more densely onto a subset of the NUMA nodes, and (b) benefits of NUMA affinity between memory allocated by one thread and accessed by other threads. We want our threads spread widely over the system and not packed together. Conceptually, when placing a new thread, the kernel picks the least loaded node NUMA node (the node with lowest aggregate load average), and then the least loaded core on that node, etc. Furthermore, the kernel places threads onto resources -- sockets, cores, pipelines, etc -- without regard to the thread's process membership. That is, initial placement is process-agnostic. Keep reading, though. This description is incorrect. On Solaris 10 on a SPARC T5440 with 4 x T2+ NUMA nodes, if the system is otherwise unloaded and we launch a process that creates 20 compute-bound concurrent threads, then typically we'll see a perfect balance with 5 threads on each node. We see similar behavior on an 8-node x86 x4800 system, where each node has 8 cores and each core is 2-way hyperthreaded. So far so good; this behavior seems in agreement with the policy I described in the 1st paragraph. I recently tried the same experiment on a 4-node T4-4 running Solaris 11. Both the T5440 and T4-4 are 4-node systems that expose 256 logical thread contexts. To my surprise, all 20 threads were placed onto just one NUMA node while the other 3 nodes remained completely idle. I checked the usual suspects such as processor sets inadvertently left around by colleagues, processors left offline, and power management policies, but the system was configured normally. I then launched multiple concurrent instances of the process, and, interestingly, all the threads from the 1st process landed on one node, all the threads from the 2nd process landed on another node, and so on. This happened even if I interleaved thread creating between the processes, so I was relatively sure the effect didn't related to thread creation time, but rather that placement was a function of process membership. I this point I consulted the Solaris sources and talked with folks in the Solaris group. The new Solaris 11 behavior is intentional. The kernel is no longer using a simple maximum dispersal policy, and thread placement is process membership-aware. Now, even if other nodes are completely unloaded, the kernel will still try to pack new threads onto the home lgroup (socket) of the primordial thread until the load average of that node reaches 50%, after which it will pick the next least loaded node as the process's new favorite node for placement. On the T4-4 we have 64 logical thread contexts (strands) per socket (lgroup), so if we launch 48 concurrent threads we will find 32 placed on one node and 16 on some other node. If we launch 64 threads we'll find 32 and 32. That means we can end up with our threads clustered on a small subset of the nodes in a way that's quite different that what we've seen on Solaris 10. So we have a policy that allows process-aware packing but reverts to spreading threads onto other nodes if a node becomes too saturated. It turns out this policy was enabled in Solaris 10, but certain bugs suppressed the mixed packing/spreading behavior. There are configuration variables in /etc/system that allow us to dial the affinity between nascent threads and their primordial thread up and down: see lgrp_expand_proc_thresh, specifically. In the OpenSolaris source code the key routine is mpo_update_tunables(). This method reads the /etc/system variables and sets up some global variables that will subsequently be used by the dispatcher, which calls lgrp_choose() in lgrp.c to place nascent threads. Lgrp_expand_proc_thresh controls how loaded an lgroup must be before we'll consider homing a process's threads to another lgroup. Tune this value lower to have it spread your process's threads out more. To recap, the 'new' policy is as follows. Threads from the same process are packed onto a subset of the strands of a socket (50% for T-series). Once that socket reaches the 50% threshold the kernel then picks another preferred socket for that process. Threads from unrelated processes are spread across sockets. More precisely, different processes may have different preferred sockets (lgroups). Beware that I've simplified and elided details for the purposes of explication. The truth is in the code. Remarks: It's worth noting that initial thread placement is just that. If there's a gross imbalance between the load on different nodes then the kernel will migrate threads to achieve a better and more even distribution over the set of available nodes. Once a thread runs and gains some affinity for a node, however, it becomes "stickier" under the assumption that the thread has residual cache residency on that node, and that memory allocated by that thread resides on that node given the default "first-touch" page-level NUMA allocation policy. Exactly how the various policies interact and which have precedence under what circumstances could the topic of a future blog entry. The scheduler is work-conserving. The x4800 mentioned above is an interesting system. Each of the 8 sockets houses an Intel 7500-series processor. Each processor has 3 coherent QPI links and the system is arranged as a glueless 8-socket twisted ladder "mobius" topology. Nodes are either 1 or 2 hops distant over the QPI links. As an aside the mapping of logical CPUIDs to physical resources is rather interesting on Solaris/x4800. On SPARC/Solaris the CPUID layout is strictly geographic, with the highest order bits identifying the socket, the next lower bits identifying the core within that socket, following by the pipeline (if present) and finally the logical thread context ("strand") on the core. But on Solaris on the x4800 the CPUID layout is as follows. [6:6] identifies the hyperthread on a core; bits [5:3] identify the socket, or package in Intel terminology; bits [2:0] identify the core within a socket. Such low-level details should be of interest only if you're binding threads -- a bad idea, the kernel typically handles placement best -- or if you're writing NUMA-aware code that's aware of the ambient placement and makes decisions accordingly. Solaris introduced the so-called critical-threads mechanism, which is expressed by putting a thread into the FX scheduling class at priority 60. The critical-threads mechanism applies to placement on cores, not on sockets, however. That is, it's an intra-socket policy, not an inter-socket policy. Solaris 11 introduces the Power Aware Dispatcher (PAD) which packs threads instead of spreading them out in an attempt to be able to keep sockets or cores at lower power levels. Maximum dispersal may be good for performance but is anathema to power management. PAD is off by default, but power management polices constitute yet another confounding factor with respect to scheduling and dispatching. If your threads communicate heavily -- one thread reads cache lines last written by some other thread -- then the new dense packing policy may improve performance by reducing traffic on the coherent interconnect. On the other hand if your threads in your process communicate rarely, then it's possible the new packing policy might result on contention on shared computing resources. Unfortunately there's no simple litmus test that says whether packing or spreading is optimal in a given situation. The answer varies by system load, application, number of threads, and platform hardware characteristics. Currently we don't have the necessary tools and sensoria to decide at runtime, so we're reduced to an empirical approach where we run trials and try to decide on a placement policy. The situation is quite frustrating. Relatedly, it's often hard to determine just the right level of concurrency to optimize throughput. (Understanding constructive vs destructive interference in the shared caches would be a good start. We could augment the lines with a small tag field indicating which strand last installed or accessed a line. Given that, we could augment the CPU with performance counters for misses where a thread evicts a line it installed vs misses where a thread displaces a line installed by some other thread.)

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  • Oracle Tutor: Top 10 to Implement Sustainable Policies and Procedures

    - by emily.chorba(at)oracle.com
    Overview Your organization (executives, managers, and employees) understands the value of having written business process documents (process maps, procedures, instructions, reference documents, and form abstracts). Policies and procedures should be documented because they help to reduce the range of individual decisions and encourage management by exception: the manager only needs to give special attention to unusual problems, not covered by a specific policy or procedure. As more and more procedures are written to cover recurring situations, managers will begin to make decisions which will be consistent from one functional area to the next.Companies should take a project management approach when implementing an environment for a sustainable documentation program and do the following:1. Identify an Executive Champion2. Put together a winning team3. Assign ownership4. Centralize publishing5. Establish the Document Maintenance Process Up Front6. Document critical activities only7. Document actual practice8. Minimize documentation9. Support continuous improvement10. Keep it simple 1. Identify an Executive ChampionAppoint a top down driver. Select one key individual to be a mentor for the procedure planning team. The individual should be a senior manager, such as your company president, CIO, CFO, the vice-president of quality, manufacturing, or engineering. Written policies and procedures can be important supportive aids when known to express the thinking for the chief executive officer and / or the president and to have his or her full support. 2. Put Together a Winning TeamChoose a strong Project Management Leader and staff the procedure planning team with management members from cross functional groups. Make sure team members have the responsibility - and the authority - to make things happen.The winning team should consist of the Documentation Project Manager, Document Owners (one for each functional area), a Document Controller, and Document Specialists (as needed). The Tutor Implementation Guide has complete job descriptions for these roles. 3. Assign Ownership It is virtually impossible to keep process documentation simple and meaningful if employees who are far removed from the activity itself create it. It is impossible to keep documentation up-to-date when responsibility for the document is not clearly understood.Key to the Tutor methodology, therefore, is the concept of ownership. Each document has a single owner, who is responsible for ensuring that the document is necessary and that it reflects actual practice. The owner must be a person who is knowledgeable about the activity and who has the authority to build consensus among the persons who participate in the activity as well as the authority to define or change the way an activity is performed. The owner must be an advocate of the performers and negotiate, not dictate practices.In the Tutor environment, a document's owner is the only person with the authority to approve an update to that document. 4. Centralize Publishing Although it is tempting (especially in a networked environment and with document management software solutions) to decentralize the control of all documents -- with each owner updating and distributing his own -- Tutor promotes centralized publishing by assigning the Document Administrator (gate keeper) to manage the updates and distribution of the procedures library. 5. Establish a Document Maintenance Process Up Front (and stick to it) Everyone in your organization should know they are invited to suggest changes to procedures and should understand exactly what steps to take to do so. Tutor provides a set of procedures to help your company set up a healthy document control system. There are many document management products available to automate some of the document change and maintenance steps. Depending on the size of your organization, a simple document management system can reduce the effort it takes to track and distribute document changes and updates. Whether your company decides to store the written policies and procedures on a file server or in a database, the essential tasks for maintaining documents are the same, though some tasks are automated. 6. Document Critical Activities Only The best way to keep your documentation simple is to reduce the number of process documents to a bare minimum and to include in those documents only as much detail as is absolutely necessary. The first step to reducing process documentation is to document only those activities that are deemed critical. Not all activities require documentation. In fact, some critical activities cannot and should not be standardized. Others may be sufficiently documented with an instruction or a checklist and may not require a procedure. A document should only be created when it enhances the performance of the employee performing the activity. If it does not help the employee, then there is no reason to maintain the document. Activities that represent little risk (such as project status), activities that cannot be defined in terms of specific tasks (such as product research), and activities that can be performed in a variety of ways (such as advertising) often do not require documentation. Sometimes, an activity will evolve to the point where documentation is necessary. For example, an activity performed by single employee may be straightforward and uncomplicated -- that is, until the activity is performed by multiple employees. Sometimes, it is the interaction between co-workers that necessitates documentation; sometimes, it is the complexity or the diversity of the activity.7. Document Actual Practices The only reason to maintain process documentation is to enhance the performance of the employee performing the activity. And documentation can only enhance performance if it reflects reality -- that is, current best practice. Documentation that reflects an unattainable ideal or outdated practices will end up on the shelf, unused and forgotten.Documenting actual practice means (1) auditing the activity to understand how the work is really performed, (2) identifying best practices with employees who are involved in the activity, (3) building consensus so that everyone agrees on a common method, and (4) recording that consensus.8. Minimize Documentation One way to keep it simple is to document at the highest level possible. That is, include in your documents only as much detail as is absolutely necessary.When writing a document, you should ask yourself, What is the purpose of this document? That is, what problem will it solve?By focusing on this question, you can target the critical information.• What questions are the end users likely to have?• What level of detail is required?• Is any of this information extraneous to the document's purpose? Short, concise documents are user friendly and they are easier to keep up to date. 9. Support Continuous Improvement Employees who perform an activity are often in the best position to identify improvements to the process. In other words, continuous improvement is a natural byproduct of the work itself -- but only if the improvements are communicated to all employees who are involved in the process, and only if there is consensus among those employees.Traditionally, process documentation has been used to dictate performance, to limit employees' actions. In the Tutor environment, process documents are used to communicate improvements identified by employees. How does this work? The Tutor methodology requires a process document to reflect actual practice, so the owner of a document must routinely audit its content -- does the document match what the employees are doing? If it doesn't, the owner has the responsibility to evaluate the process, to build consensus among the employees, to identify "best practices," and to communicate these improvements via a document update. Continuous improvement can also be an outgrowth of corrective action -- but only if the solutions to problems are communicated effectively. The goal should be to solve a problem once and only once, which means not only identifying the solution, but ensuring that the solution becomes part of the process. The Tutor system provides the method through which improvements and solutions are documented and communicated to all affected employees in a cost-effective, timely manner; it ensures that improvements are not lost or confined to a single employee. 10. Keep it Simple Process documents don't have to be complex and unfriendly. In fact, the simpler the format and organization, the more likely the documents will be used. And the simpler the method of maintenance, the more likely the documents will be kept up-to-date. Keep it simply by:• Minimizing skills and training required• Following the established Tutor document format and layout• Avoiding technology just for technology's sake No other rule has as major an impact on the success of your internal documentation as -- keep it simple. Learn More For more information about Tutor, visit Oracle.Com or the Tutor Blog. Post your questions at the Tutor Forum.   Emily Chorba Principle Product Manager Oracle Tutor & BPM 

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  • SOA Implementation Challenges

    Why do companies think that if they put up a web service that they are doing Service-Oriented Architecture (SOA)? Unfortunately, the IT and business world love to run on the latest hype or buzz words of which very few even understand the meaning. One of the largest issues companies have today as they consider going down the path of SOA, is the lack of knowledge regarding the architectural style and the over usage of the term SOA. So how do we solve this issue?I am sure most of you are thinking by now that you know what SOA is because you developed a few web services.  Isn’t that SOA, right? No, that is not SOA, but instead Just Another Web Service (JAWS). For us to better understand what SOA is let’s look at a few definitions.Douglas K. Bary defines service-oriented architecture as a collection of services. These services are enabled to communicate with each other in order to pass data or coordinating some activity with other services.If you look at this definition closely you will notice that Bary states that services communicate with each other. Let us compare this statement with my first statement regarding companies that claim to be doing SOA when they have just a collection of web services. In order for these web services to for an SOA application they need to be interdependent on one another forming some sort of architectural hierarchy. Just because a company has a few web services does not mean that they are all interconnected.SearchSOA from TechTarget.com states that SOA defines how two computing entities work collectively to enable one entity to perform a unit of work on behalf of another. Once again, just because a company has a few web services does not guarantee that they are even working together let alone if they are performing work for each other.SearchSOA also points out service interactions should be self-contained and loosely-coupled so that all interactions operate independent of each other.Of all the definitions regarding SOA Thomas Erl’s seems to shed the most light on this concept. He states that “SOA establishes an architectural model that aims to enhance the efficiency, agility, and productivity of an enterprise by positioning services as the primary means through which solution logic is represented in support of the realization of the strategic goals associated with service-oriented computing.” (Erl, 2011) Once again this definition proves that a collection of web services does not mean that a company is doing SOA. However, it does mean that a company has a collection of web services, and that is it.In order for a company to start to go down the path of SOA, they must take  a hard look at their existing business process while abstracting away any technology so that they can define what is they really want to accomplish. Once a company has done this, they can begin to factor out common sub business process like credit card process, user authentication or system notifications in to small components that can be built independent of each other and then reassembled to form new and dynamic services that are loosely coupled and agile in that they can change as a business grows.Another key pitfall of companies doing SOA is the fact that they let vendors drive their architecture. Why do companies do this? Vendors’ do not hold your company’s success as their top priority; in fact they hold their own success as their top priority by selling you as much stuff as you are willing to buy. In my experience companies tend to strive for the maximum amount of benefits with a minimal amount of cost. Does anyone else see any conflicts between this and the driving force behind vendors.Mike Kavis recommends in an article written in CIO.com that companies need to figure out what they need before they talk to a vendor or at least have some idea of what they need. It is important to thoroughly evaluate each vendor and watch them perform a live demo of their system so that you as the company fully understand what kind of product or service the vendor is actually offering. In addition, do research on each vendor that you are considering, check out blog posts, online reviews, and any information you can find on the vendor through various search engines.Finally he recommends companies to verify any recommendations supplied by a vendor. From personal experience this is very important. I can remember when the company I worked for purchased a $200,000 add-on to their phone system that never actually worked as it was intended. In fact, just after my departure from the company started the process of attempting to get their money back from the vendor. This potentially could have been avoided if the company had done the research before selecting this vendor to ensure that their product and vendor would live up to their claims. I know that some SOA vendor offer free training regarding SOA because they know that there are a lot of misconceptions about the topic. Superficially this is a great thing for companies to take part in especially if the company is starting to implement SOA architecture and are still unsure about some topics or are looking for some guidance regarding the topic. However beware that some companies will focus on their product line only regarding the training. As an example, InfoWorld.com claims that companies providing deep seminars disguised as training, focusing more about ESBs and SOA governance technology, and less on how to approach and solve the architectural issues of the attendees.In short, it is important to remember that we as software professionals are responsible for guiding a business’s technology sections should be well informed and fully understand any new concepts that may be considered for implementation. As I have demonstrated already a company that has a few web services does not mean that they are doing SOA.  Additionally, we must not let the new buzz word of the day drive our technology, but instead our technology decisions should be driven from research and proven experience. Finally, it is important to rely on vendors when necessary, however, always take what they say with a grain of salt while cross checking any claims that they may make because we have to live with the aftermath of a system after the vendors are gone.   References: Barry, D. K. (2011). Service-oriented architecture (SOA) definition. Retrieved 12 12, 2011, from Service-Architecture.com: http://www.service-architecture.com/web-services/articles/service-oriented_architecture_soa_definition.html Connell, B. (2003, 9). service-oriented architecture (SOA). Retrieved 12 12, 2011, from SearchSOA: http://searchsoa.techtarget.com/definition/service-oriented-architecture Erl, T. (2011, 12 12). Service-Oriented Architecture. Retrieved 12 12, 2011, from WhatIsSOA: http://www.whatissoa.com/p10.php InfoWorld. (2008, 6 1). Should you get your SOA knowledge from SOA vendors? . Retrieved 12 12, 2011, from InfoWorld.com: http://www.infoworld.com/d/architecture/should-you-get-your-soa-knowledge-soa-vendors-453 Kavis, M. (2008, 6 18). Top 10 Reasons Why People are Making SOA Fail. Retrieved 12 13, 2011, from CIO.com: http://www.cio.com/article/438413/Top_10_Reasons_Why_People_are_Making_SOA_Fail?page=5&taxonomyId=3016  

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  • Reset DRAC to factory defaults

    - by yakatz
    I put a DRAC that has not been used in a long time into a PowerEdge 1750 running CentOS 5.8. Because we run our DRACs on a separate network, we don't change the password from the default (root/calvin), but evidently someone changed this one. I tried the regular command line reset (racadm racresetcfg), but I get the following error: ERROR: Unable to perform requested operation. If the operation attempted was to configure DRAC, possible reason may be that Local Configuration using RACADM is disabled. This implies to me that racadm is able to communicate, but there is a setting on the DRAC that is preventing it from working. I was not able to find any references to this error in any Dell documentation. Has anyone seen this problem and/or know what I can do about it? (The DRAC is useless is I can't log in to it.)

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  • Unable to configure DD-WRT SNMP monitoring with Zabbix

    - by Jien Wai
    Installed Zabbix on Ubuntu but not sure what setting I missed. Base on my concept, I would like to using SNMP to monitoring DD-WRT router which it using SNMP service. I did enable to SNMP service at DD-WRT router page. And also created a host at Zabbix with included DD-WRT template. After I done it I still unable to get any connection/information at Zabbix which mean the router doesn't communicate with Zabbix. The above picture is my DD-WRT's SNMP configuration. http://img13.imageshack.us/img13/2228/rhj2.png Also this is the Zabbix configuration which I have created the service to monitoring my DD-WRT router. http://imageshack.us/a/img853/7311/hlpr.png

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  • Getting a VMnet0 error in VMWare workstation after updating host computer from Windows 8 to 8.1

    - by Andrew
    Yesterday, I updated my computer from Windows 8 to 8.1. I have VMWare Workstation 10 running Windows XP on this computer and prior to the update I had no issues connecting to my network. However, since updating, I haven't been able to connect to any network and I'm getting the following error: "The network bridge on device VMnet0 is not running. The firtual machine will not be able to communicate with the host or with other machines on your network. Failed to connect virtual device Ethernet0" I've checked all of my settings which currently have my network adapter set for a bridged connection and under device status "connected" is checked. Not really sure where to go from here, but after doing some research I have seen that others users have reported getting this error when updating the OS (any OS, not windows 8 specifically) of the host computer. Thanks in advance to anyone who can help.

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  • Allowing creation/modification of virtual aliases using web.config

    - by user25018
    Hi, I've been given a problem to fix, and I initially thought of .htaccess files, except for one thing, I quickly realized it's an IIS server. Is it possible to allow a webmaster the ability to modify the virtual directories using web.config files in the same way you can using .htaccess files? If so, any ideas on where I can find details on how this is done that I can communicate with the end client? We want to be able to do this without having to provide access to the IIS console to the webmaster. An example of the desired change is: http://FQDN/Careers/Careers.aspx?locale=en-ca&uid=Careers have http:FQDN/careers point to the above, but modified/added/removed by the end user using web.config

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  • Most efficient way to connect an ISAPI Dll to a windows service

    - by Mike Trader
    I am writing a custom server for a client. They want scalability so I must use a thread pool and probably I/O completion port to regulate it. The main requirement is that a windows service manage the HTTP requests for a number of reasons. An example of one would be that a client session spans many requests and continuity must be maintained. Another would be that the ISAPI Dll will be in the IIS address space and so it's code will be lean and very carefully implemented. The extensive processing in the Windows service may get unruly for the duration of the lengthy development. If the service crashes it will not take out IIS. Anyway, the remaining decision is how to have these two processes communicate. We have talked about pipes, tcp, global memory and even a single pipe with multiplexed data ala FastCGI. Would love to hear anyones experience with a decision like this.

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  • Can't ping host from vmware guest using bridged networking

    - by user199421
    Host is Windows 7 Guest is Ubuntu 11.04 Network adapter is wireless I can ping other computers on the network but not the host. No firewall are involved. Sniffing the traffic with wireshark it looks like both the host and the guest are using the same MAC address. My guest simply doesn't receive a reply when asking for 192.168.1.101 (the host) My router has no problem giving both of them different IP addresses but maybe duplicate MAC address is the problem? It seems logical that both will have the same MAC address (from the host point of view) but it strange that there is no work around for this because otherwise I don't see how the host and guess are supposed to communicate.

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  • How to configure Linux to act as a Bluetooth RFCOMM SPP server?

    - by regulatre
    I'm writing a phone app for Android that connects to a bluetooth RFCOMM device in my car. My phone app talks AT commands with it. For development work, I often need to communicate with the device to try different commands and things. My neighbors are starting to think I'm weird because I sit in my car for hours on end with my laptop screen shining on my face, typing away like a script kiddie. I'd much rather configure one of my many Linux servers to act as a bluetooth RFCOMM device and allow me to connect to it (indoors, while I sit on my couch). I imagine I have to start with something like sdptool add SP But then what? I'm perfectly happy writing a perl app to handle the I/O, but I just don't know how to make the bluez stack accept connections and subsequently pipe that stream to a perl app.

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  • Poor home office network performance and cannot figure out where the issue is

    - by Jeff Willener
    This is the most bizarre issue. I have worked with small to mid size networks for quite a long time and can say I'm comfortable connecting hardware. Where you will start to lose me is with managed switches and firewalls. To start, let me describe my network (sigh, shouldn't but I MUST solve this). 1) Comcast Cable Internet 2) Motorola SURFboard eXtreme Cable Modem. a) Model: SB6120 b) DOCSIS 3.0 and 2.0 support c) IPv4 and IPv6 support 3-A) Cisco Small Business RV220W Wireless N Firewall a) Latest firmware b) Model: RV220W-A-K9-NA c) WAN Port to Modem (2) d) vlan 1: work e) vlan 2: everything else. 3-B) D-Link DIR-615 Draft 802.11 N Wireless Router a) Latest firmware b) WAN Port to Modem (2) 4) Servers connected directly to firewall a) If firewall 3-A, then vlan 1 b) CAT5e patch cables c) Dell PowerEdge 1400SC w/ 10/100 integrated NIC (Domain Controller, DNS, former DHCP) d) Dell PowerEdge 400SC w/ 10/100/1000 integrated NIC (VMWare Server) 4) Linksys EZXS88W unmanaged Workgroup 10/100 Switch a) If firewall 3-A, then vlan 2 b) 25' CAT5e patch cable to firewall (3-A or 3-B) c) Connects xBox 360, Blu-Ray player, PC at TV 5) Office equipment connected directly to firewall a) If firewall 3-A, then vlan 1 b) ~80' CAT6 or CAT5e patch cable to firewall (3-A or 3-B) c) Connects 1) Dell Latitude laptop 10/100/1000 2) Dell Inspiron laptop 10/100 3) Dell Workstation 10/100/1000 (Pristine host, VMWare Workstation 7.x with many bridged VM's) 4) Brother Laser Printer 10/100 5) Epson All-In-One Workforce 310 10/100 5-A) NetGear FS116 unmanaged 10/100 switch a) I've had this switch for a long time and never had issues. 5-B) NetGear GS108 unmanaged 10/100/1000 switch a) Bought new for this issue and returned. 5-C) Linksys SE2500 unmanaged 10/100/1000 switch a) Bought new for this issue and returned. 5-D) TP-Link TL-SG10008D unmanaged 10/100/1000 a) Bought new for this issue and still have. 6) VLan 1 Wireless Connections (on same subnet if 3-B) a) Any of those at 5c b) HP Laptop 7) VLan 2 Wireless Connection (on same subnet if 3-B) a) IPad, IPod b) Compaq Laptop c) Epson Wireless Printer Shew, without hosting a diagram I hope that paints a good picture. The Issue The breakdown here is at item 5. No matter what I do I cannot have a switch at 5 and have to run everything wireless regardless of router. Issues related to using a switch (point 5 above) SpeedTest is good. Poor throughput to other devices if can communicate at all. Usually cannot ping other devices even on the same switch although, when able, ping times are good. Eventual lose of connectivity and can "sometimes" be restored by unplugging everything for several days, not minutes or hours but we're talking a week if at all. Directly connect to computer gives good internet connection however throughput to other devices connected to firewall is at best horrible. Yet printing doesn't seem to be an issue as long as they are connected via wireless. I have to force the RV220W to 1000Mb on the respective port if using a Gig Switch Issues related to using wireless in place of a switch (point 5 above) Poor throughput to other devices if can communicate. SpeedTest is good. Bottom line Internet speeds are awesome. By the way, Comcast went WAY above and beyond to make sure it was not them. They rewired EVERYTHING which did solve internet drops. Computer to computer connections are garbage Cannot get switch at 5 to work, yet other at 4 has never had an issue. Direct connection, bypass switch, is good for DHCP and internet. DNS must be on server, not firewall. Cisco insists its my switches but as you can see I have used four and two different cables with the same result. My gut feeling is something is happening with routing. But I'm not smart enough to know that answer. I run a lot of VM's at 5-c-3, could that cause it? What's different compared to my previous house is I have introduced Gigabit hardware (firewall/switches/computers). Some of my computers might have IPv6 turned on if I haven't turned it off already. I'm truly at a loss and hope anyone has some crazy idea how to solve this. Bottom line, I need a switch in my office behind the firewall. I've changed everything. The real crux is I will find a working solution and, again, after days it will stop working. So this means I cannot isolate if its a computer since I have to use them. Oh and a solution is not throwing more money at this. I'm well into $1k already. Yah, lame.

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  • What's required to configure Ubuntu to use a specific DNS server?

    - by ks78
    I've setup two Amazon EC2 instances, both running Ubuntu Server. One is configured as a DNS server running bind9, which will be used to allow EC2 instances to communicate with each other based on hostname rather than IP, since their private IPs may change. I think I have the DNS server setup correctly. I want to use the second EC2 instance to test the DNS server. Using Webmin, I've added the DNS server's private IP to the client's DNS Servers list and added the domain to the Search Domains list. I did have to edit /etc/dhcp3/dhclint.conf to make my changes stick. After reboot, I expected I'd be able to ping or nslookup the DNS server from the test client, but it can't seem to find the server. Is there something I'm missing? What's required to configure an Ubuntu client to use a DNS server? I just want to make sure I'm not missing something before I assume the server's the problem.

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  • coordinating a script to run on only one of identical load-balanced servers

    - by Amos Shapira
    I have two identically configured CentOS 5 servers (possibly more in the future). I need to run a cron job on any one of them and that it'll run only on one of them. I know about RedHat Cluster Suite (we use it on other servers), but it's a too big a gun to use for this task, plus it doesn't really behave well for less than three nodes. Is there anything light-weight I can use for that? The servers can communicate with each other directly. I suppose I can develope something over ssh or nrpe (two server which are already installed on these servers), but I was wondering whether there is something already available.

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  • How to connect devices behind Comcast router/modem with devices behind wireless router

    - by deeperDATA
    I know this is going to seem like a simple solution but I have been unable to find a clear answer through Google. Simple office setup: I have a Comcast modem/router that has 4 hard wired ports. In one of those ports I have a Cisco wireless router which also has 4 of its own ports. What is the method for getting devices behind the modem/router to ping/communicate with devices behind the wireless router? They are all on the same subnet but the IP ranges differ. The router produces 192.168.1.1 by default while the Comcast modem/router produces 10.1.10.1 by default. I think what I'm attempting to do might be considered "extending" the modem/router's network but I'm not sure. Thank you in advance for your assistance.

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  • How to use suse linux as a small router

    - by Mingo
    I has 2 subnet 192.168.1.0/24 and 192.168.2.0/24 and one suse linux, the linux has 2 interface, eth0 and eth1. I want to configurate the suse linux as a router so that make these 2 subnet can communicate with each other. This is my steps: 1.set the linux eth0 ip as 192.160.1.254,eth1 ip 192.168.2.254 2.add route in linux: route add -net 192.168.1.0 netmask 255.255.255.0 dev eth0 route add -net 192.168.2.0 netmask 255.255.255.0 dev eth1 3.set 192.168.1.0/24 gw as 192.168.1.254,and 192.168.2.0/24 gw as 192.168.2.254 I am not sure this will work or not? or some step i missing?

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  • Cant route VLAN over VPN between Cisco ASA 5505 and Cisco 870

    - by user60984
    We've had an existing VPN between a 5505 and 870 for some time. We've just added VLANs to the network on the 5505 side. We can't seem to figure out how to get devices on the VLANs to communicate with devices on the 870 network which have no VLANs. We're thinking we might have to use a router of sorts to handle the routing before hitting the ASA. We thought PFsense might work well. We've been banging our heads against this thing for 2 days so any immediate help would be great. We're up against a deadline. Thanks!!!

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  • Cannot access virtual machine via ping from the physical host machine

    - by Kenni
    I'm installing a FreeBSD Server on VirtualBox. I set up the IP address (192.168.10.5) for the virtual server to run a mail server and the host computer(Windows 7) with 192.168.10.184. The two machines cannot communicate or connect to each other. I cannot ping from the virtual machine to the host and vice versa. The host machine connects to a LAN. I want the mail server to run frm a VMachine. I think it's a problem with the network configuration of the virtual machine.

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