Search Results

Search found 1086 results on 44 pages for 'switches'.

facebook twitter digg google delicious technorati stumbleupon myspace wordpress linkedin gmail igoogle windows live tumblr viadeo yahoo buzz yahoo mail yahoo bookmarks favorites email print

Page 5/44 | < Previous Page | 1 2 3 4 5 6 7 8 9 10 11 12  | Next Page >

  • Two cisco gigabit switches refuse to link to each other. Any idea why?

    - by Prody
    I have 3 Linksys SR2024 switches which are basically non-managed 24 port Gbit + 2 miniGBIC. I now had to add another switch to the network, and my provider didn't have the SR2024 switch anymore, so I got the Cisco SLM2024 which was a bit more expensive. It's pretty much the same thing but with management (that I don't need). So I've connected the SLM2024 to a SR2024 via Cat6 cable, and for some strange reason, I get no link. If I connect any machine with a Gbit NIC to both switches, it links with 1Gbit autonegotiated. If I connect the SLM2024 to a non-Gbit switch (I have a cheap 4port ASUS switch), it will link just fine on 100Mbit full duplex. Since the SLM2024 has management, I've tried to see if something is misconfigured on it's side, but it's not, it advertises 1Gbit and lower. (hence the machines connecting succesfully at 1Gbit). Since the SR2024 that I'm trying to connect it to also connects successfully with another SR2024 and other Gbit machines, it means that it advertises Gbit too. But for some reason when I link the SR2024 to the SLM2024 I get no link. Please note that I've properly tested the wire. Does anyone have any idea what's wrong?

    Read the article

  • How does Brocade (Foundry) FastIron CX compare to Cisco 3750 stackable switches?

    - by Paul
    We're considering Brocade's CX series vs. Cisco's 3750 at both core and distribution layers for a new site with gig to desktop, without POE. If you have any hands-on experience with FastIron CX switches, I would greatly value your impressions. I'll gladly add mine to the discussion when we get some quality time with our eval units (one just arrived yesterday, another's on the way). Thank you!

    Read the article

  • How to make a queue switches from FIFO mode to priority mode?

    - by enzom83
    I would like to implement a queue capable of operating both in the FIFO mode and in the priority mode. This is a message queue, and the priority is first of all based on the message type: for example, if the messages of A type have higher priority than the messages of the B type, as a consequence all messages of A type are dequeued first, and finally the messages of B type are dequeued. Priority mode: my idea consists of using multiple queues, one for each type of message; in this way, I can manage a priority based on the message type: just take first the messages from the queue at a higher priority and progressively from lower priority queues. FIFO mode: how to handle FIFO mode using multiple queues? In other words, the user does not see multiple queues, but it uses the queue as if it were a single queue, so that the messages leave the queue in the order they arrive when the priority mode is disabled. In order to achieve this second goal I have thought to use a further queue to manage the order of arrival of the types of messages: let me explain better with the following code snippet. int NUMBER_OF_MESSAGE_TYPES = 4; int CAPACITY = 50; Queue[] internalQueues = new Queue[NUMBER_OF_MESSAGE_TYPES]; Queue<int> queueIndexes = new Queue<int>(CAPACITY); void Enqueue(object message) { int index = ... // the destination queue (ie its index) is chosen according to the type of message. internalQueues[index].Enqueue(message); queueIndexes.Enqueue(index); } object Dequeue() { if (fifo_mode_enabled) { // What is the next type that has been enqueued? int index = queueIndexes.Dequeue(); return internalQueues[index].Dequeue(); } if (priority_mode_enabled) { for(int i=0; i < NUMBER_OF_MESSAGE_TYPES; i++) { int currentQueueIndex = i; if (!internalQueues[currentQueueIndex].IsEmpty()) { object result = internalQueues[currentQueueIndex].Dequeue(); // The following statement is fundamental to a subsequent switching // from priority mode to FIFO mode: the messages that have not been // dequeued (since they had lower priority) remain in the order in // which they were queued. queueIndexes.RemoveFirstOccurrence(currentQueueIndex); return result; } } } } What do you think about this idea? Are there better or more simple implementations?

    Read the article

  • Linux bonded Interfaces hanging periodically

    - by David
    I've several hosts that are showing problems with connectivity. When working from the command line, for example, typing is frozen for a second or so, then recovers - then it does it again. The most egregious example host would freeze (input) for 15-30 seconds, then recover and go out 5 seconds later. Switching cables didn't do anything - but removing one of the physical cables caused everything to clear up instantly (which why I think this is a network problem). Looking at the network I couldn't see any packets floating that would explain this. These ethernet interfaces (Gigabit Dell) were working normally previously, but since we moved the systems - and put them on a new set of switches - this has been a problem on multiple theoretically identically-configured hosts. The original switches were an HP Procurve 1810-24G and an HP Procurve 1800-24G connected with LLDP; the new switches are both Cisco SG 200-26, which I understand are rebranded Linksys switches. Is this caused by a problem with the switches? Is it the switch configurations? Are the Cisco switches incapable of handling this? I don't see where the configuration is located; I searched the usual /etc/sysconfig/network/devices but there's nothing in there about options (like mii polling) and nothing about the method of balancing the two. Searching scripts, I can't find anything in /etc/init.d/network either. The hosts are almost all Red Hat Enterprise Linux 5.x systems (5.6, 5.7) but some are Ubuntu Server 10.04.3 Lucid Lynx. I need help with both if it comes to that. UPDATE: We're also seeing some problems with servers on the original switches. The HP switches and the Cisco switches are also interconnected (temporarily); there is a cable run from one switch to the next. Pings on any of these hosts show about one ICMP packet out of every 5-6 getting dropped (timed out). Could there be an interaction between the two switches? Oh, and the hosts are using bonding with Balance-RR as the method.

    Read the article

  • Procurve Primary VLAN

    - by fukawi2
    I'm trying to depreciate usage of VLAN 1 on my ProCurve switches; 1 is unused. I understand that VLAN 1 must exist, but I want to remove it from all ports, especially trunks between switches. The problem I have is that stacking does not seem to work without VLAN 1. I have changed the primary VLAN and management VLAN on all the switches: (config)# primary-vlan 42 (config)# management-vlan 42 (config)# no vlan 1 untagged 25 Port 25 is the link between the 2 switches I'm testing with; the stack master and a member switch; I only want tagged traffic between the switches, no untagged frames. show stacking on the master shows all members as "UP" but I can not telnet any of them: Telnet failed: Connection timed out. All switches have manually assigned (static) IP addresses on VLAN 42, and all exist in the same /25 subnet, as does my desktop. I can telnet the switches directly from my desktop to the individual switch IP addresses, just not from the master switch. Do I need to reboot the switches to have the primary-vlan change take effect? Or is there something else I'm missing?

    Read the article

  • Why does cat not use options the way I expect UNIX programs to use switches?

    - by Chas. Owens
    I have been a UNIX user for more years than I care to think about, and in that time I have been trained to expect that when contradictory switches are given to a program the last one wins. Recently I have noticed that cat -bn file and cat -nb file both use the -b option (number blank lines) over the -n option (number all lines). I get this behavior on both BSD and Linux, so I don't think it is an implementation quirk. Is this something that is specified somewhere and am I just crazy for expecting the first example to number all lines?

    Read the article

  • Bootcamp's "Use all F1, F2, etc. keys" switches back automatically

    - by cheeesus
    I use Windows 7 in a Bootcamp partition on my iMac. I always check the option "Use all F1, F2, etc. keys as standard function keys", and when it's checked, everything works great. But recently, something switches this setting back to 'unchecked' every few minutes. I constantly have to open the Boot Camp Control Panel, uncheck the checkbox, check it again and click on 'Apply'. And five minutes later, the F2 key again controls the brightness of the screen and not the renaming of files in Explorer. This is driving me mad. What could be the cause of this? Is there a keystroke to switch this feature?

    Read the article

  • Maxivista vs. Synergy vs. hardware KVM switches [closed]

    - by GetFree
    I have 2 PCs on my desk, each one with its own screen, mouse and keyboard. And it's a pain moving from one PC to the other (even though they are one foot away from each other). So, it's time to change to different approach: KVM switches. What would you recommend for a setup like mine? I dont need to change monitors since they are both in front of me. I just need a way to change mouse and keyboard. I use Windows on both PCs and money is not an issue if it worth it. What would be the best option for a seamless integration of the two PCs? Edit: What about other software similar to Synergy, like Input Director? What's more convenient in your experience?

    Read the article

  • Ubuntu 14.04 stalling. Problem with LightDM. Plymouth (and logging out) switches over to a black screen w/ white cursor

    - by Kage
    if its a duplicate, sorry. Couldn't find anything that fits my issue, much less that was on 14.04. I changed a few things recently. Switched to the Numix theme (from PPA), installed lm-sensors and psensor (ran all the I/O probes), Ubuntu Tweak, Pinta, and well, Team Fortress 2 on Steam. :P The system will get to the Plymouth 'ubuntu' screen, load load, all dots filled, switches over to LightDM, but wait! No LightDM. :I Just a blank screen with that white cursor. Can't switch out to tty1-6 - not sure if the Ctrl-Alt-F1 is disabled in 14.04 or if its literally just locked down. If I change any files, I have access to the filesystem from my Windows 8 partition. That's it. :/ I'm pretty familiar with Linux, especially Ubuntu, but I think I'm still at the point I know just enough to break things and not always how to fix 'em. Any help would be greatly appreciated. Thanks! UPDATE I was just able to get into my desktop briefly. I booted Ubuntu. When the black screen froze, I hit Ctrl-Alt-Del. When it started switching off, I hit Ctrl-Alt-Backspace. It rebooted. I plugged the second monitor in I had been using before the issue ever came about. Plymouth displayed on both. LightDM came up, displayed on both (it used to show only the ubuntu logo on the unfocused monitor though). I logged in just fine. Even ran some pending software updates. I logged out of the desktop though, and LightDM refused to show again. xP

    Read the article

  • Are there any 5.1 surround audio switches on the market?

    - by thepurplepixel
    (Somewhat related to this question) I have a set of Logitech 5.1 surround speakers, which use 3 stereo 3.5mm TRS connectors (minijacks) to transfer the audio (the typical green/black/orange audio outputs). I have a Griffin Firewave hooked up to my MacBook Pro, and my desktop has a Realtek ALC889 audio chipset. I have looked for a way to, essentially, switch the speaker inputs between my Firewave and my desktop without having to disconnect the cables from one, route them around my desk, and plug them into the other. I'd love to have something like an old Belkin DB-25/LPT switch, but for these audio cables. Of course, purchasing one and soldering my own cables on the connection terminals is always an option, but, is there a reasonably priced 5.1 audio switch (or 3x stereo) on the market that will accomplish the simple task of switching audio outputs between two computers into a set of 5.1 speakers? Thanks in advance!

    Read the article

  • Best way to provide redundant switching/links to server

    - by Myles Gray
    We have 3x ESX hosts and 2x SANS that we wish to move to a redundant 10G networking infrastructure. We have 4x Dell PowerConnect 8024F's to provide our backbone and are configured as so (only core switches relevant to this question): So the questions are: 1) Do the interconnects between the 4x 8024F's need to be LAG'd or just STP'd 2) As the NICs on the servers are split across 2 switches, does any special configuration need to be done here or on the switches? 3) If a link or switch fails will the switches automatically find a new path to the Server/SAN?

    Read the article

  • Ubuntu Natty 11.04, Turning the wireless switch off; switches it off permanently!

    - by ZiGi
    i'm using an hp pavilion dv2000 i turned the wifi switch off by mistake, the LED turned orange and the wifi got disconnected. and now when i turn the switch on, it remains orange and the wifi still isn't functional. this happened before; i found a fix that worked searching google. it was done via terminal commands and i didn't have to download anything but i can't find the solution anymore! wlan0 shows up when i use: :~$iwconfig #BLA BLA BLA #... wlan0 IEEE 802.11abg ESSID:off/any Mode:Managed Access Point: Not-Associated Tx-Power=off Retry long limit:7 RTS thr:off Fragment thr:off Power Management:off more results: :~$ sudo ifconfig wlan0 up SIOCSIFFLAGS: Operation not possible due to RF-kill :~$ rfkill list all 1: phy0: WirelessLAN Soft blocked: yes Hard blocked: yes :~$ sudo rfkill unblock all :~$ rfkill list all 1: phy0: WirelessLAN Soft blocked: no Hard blocked: yes :~$ sudo ifconfig wlan0 up SIOCSIFFLAGS: Operation not possible due to RF-kill it's still hard blocked! even though the switch is turned on; gives the same result eitherways a direction to a page with a working solution is a much appreciated answer!

    Read the article

  • Ubuntu Natty 11.04, Turning the wireless switch off; switches it off permanently!

    - by ZiGi
    i'm using an hp pavilion dv2000 i turned the wifi switch off by mistake, the LED turned orange and the wifi got disconnected. and now when i turn the switch on, it remains orange and the wifi still isn't functional. this happened before; i found a fix that worked searching google. it was done via terminal commands and i didn't have to download anything but i can't find the solution anymore! wlan0 shows up when i use: :~$iwconfig #BLA BLA BLA #... wlan0 IEEE 802.11abg ESSID:off/any Mode:Managed Access Point: Not-Associated Tx-Power=off Retry long limit:7 RTS thr:off Fragment thr:off Power Management:off more results: :~$ sudo ifconfig wlan0 up SIOCSIFFLAGS: Operation not possible due to RF-kill :~$ rfkill list all 1: phy0: WirelessLAN Soft blocked: yes Hard blocked: yes :~$ sudo rfkill unblock all :~$ rfkill list all 1: phy0: WirelessLAN Soft blocked: no Hard blocked: yes :~$ sudo ifconfig wlan0 up SIOCSIFFLAGS: Operation not possible due to RF-kill it's still hard blocked! even though the switch is turned on; gives the same result eitherways a direction to a page with a working solution is a much appreciated answer!

    Read the article

  • Why should I use a switched network over routed?

    - by SRobertJames
    Now that routers are affordable, why should I build a network using Layer 2 switches, which degenerate to broadcasting under poor conditions, and not just use real routing at Layer 3? Edit: Got some great replies. Let me clarify the question: Of course, at the lowest level, you want to plug your end nodes into a switch, not a router (as demonstrated by AlReece). I'm referring to switches which are used to bridge traffic between segments - that is, switches connected to other switches.

    Read the article

  • VMware two vSwitches Guests can't communicate between them

    - by Aaron R.
    I have some servers in this configuration: And I am not able, from VMGuest1, to ping either VMGuest3 or VMGuest4. I can, however, ping Host1 and Host2, which are attached to pSwitch1. The behavior is the same with VMGuest3 or 4 trying to ping VMGuest 1 or 2. I don't have promiscuity enabled for any of these switches, nor do I have a bridge set up inside ESXi for the virtual switches. I know that one of these options is usually necessary when trying to get connectivity between two virtual switches. These switches are connected, however, through their respective physical switches which are bridged together. Ping just times out, arp request looks like this: [root@vmguest1:~]# arp -a vmguest3 vmguest3.example.com (1.2.3.4) at <incomplete> on eth0 [root@vmguest1:~]# arp -a host1 host1.example.com (1.2.3.5) at 00:0C:64:97:1C:FF [ether] on eth0 VMGuest1 can reach hosts on pSwitch1, so why can't it get to hosts on vSwitch1 through pSwitch1 the same way?

    Read the article

  • VMware vSwitches and spanning tree

    - by dunxd
    I have two redundant core switches I want to connect to a new vSwitch I am setting up on a VMware ESX host. The switch will have two physical NICs each of which will connect to one of the core switches. The core switches are connected. If this was a physical switch, I would worry about connecting it to both core switches, because this would create a network loop. Do I need to worry about this for a VMware virtual switch? VMware's documentation says it is not possible to connect two vSwitches in a loop, therefore STP is not required. However, I am worried about connecting two physical switches together via a vSwitch.

    Read the article

  • How to wire 20 computers and 20 phones and 1 server into LAN?

    - by John Smith
    I have currently 3 switches Two Netgear JFS524 with 24 slots, One Belkin with 16 slots. Server DSL Internet Router. Main question is how to connect switches together, two Netgear's are next to each other, yet one is about 100 feet away and holds about 5 computer and 5 phones. If i connect them with only 1 wire will that limit bandwidth? e.g. all 23 computers will be limited to speed of one CAT5e cable? If i connect switches with 2 cables will this give speed boost? What's the ideal scenario should i just move the third switch next to other two? Will the speed of computer connected to white switch be same as computer connected to top switch? Will moving white switch right next top switch and having 16 wires comming 100 feet instead of 1 wire comming 100 feet make it faster? EDIT 1: I actually have NETGEAR ProSafe GS105 Gigabit switch its only has 4 ports in it though, you think i can have use of it in current setup? Like connect all 3 switches and server into it and keep internet router and phone server on one of the slower switches EDIT 2: Everyone mention gigabit switches, but will they do any difference with 10/100 network cards? I then have to use gigabit cards in every computer too? I could in server perhaps, but users will be 10/100

    Read the article

  • What characters are illegal in Cisco IOS username secret passwords?

    - by Alain O'Dea
    I am using username secret to add users with encrypted passwords to our switches and firewall. I have been battling with the same switches and firewall for a couple of hours trying to get securely generated hard passwords for all admins. Sometimes, the passwords would go into config, but wouldn't work for login. According to the documentation for enable secret a password must not begin with a number and ? has to be entered as Ctrl-V then ? to escape it. I followed that and still got passwords I could not use sometimes. There was no error when I ran username, but the password would be rejected on login by some, but not all of the switches. They are all WS-C2960-48PST-L. The passwords it didn't like contained back ticks "`" (that character under tilde ~ under Esc). The "misbehaving" switches are running: Cisco IOS Software, C2960 Software (C2960-LANBASEK9-M), Version 12.2(50)SE5, RELEASE SOFTWARE (fc1) The "working" switches are running: Cisco IOS Software, C2960 Software (C2960-LANBASEK9-M), Version 12.2(46)SE, RELEASE SOFTWARE (fc2). The "misbehaving" switches are running a newer IOS, so this suggests a regression introduced somewhere between 12.2(46)SE and 12.2(50)SE5. I was unable to find any evidence of this being intentional in the release notes for 12.2(50)SE. I would like to avoid this next time the passwords are changed :) What characters are illegal in Cisco IOS username secret passwords? Thank you for your help :)

    Read the article

  • What to look for in a switch with LAN/WAN verses an iSCSI SAN?

    - by Luke
    I'm setting up a VMWare ESXi 5 environment with 3 server nodes. Dell recommended 2x Force10 S60 switches shared (iSCSI SAN, LAN/WAN). The S60 switches are extremely powerful. They have 1.25 GB of buffer cache, < 9us latency. But they are very expensive (online price ~$15k per switch, actual quote a little less). I've been told that "by the book" you should at least have 2 internal switches for SAN, and 2 switches for LAN/WAN (each with a redundant). I know some of the pros and cons of each approach. What I'm wondering is, would it be more cost effective to disjoin the SAN from LAN with less expensive switches? The answer to this question highlights what I should be looking for in a switch for the SAN. What should I be looking for in a LAN/WAN switch, in comparison to the SAN? With the above linked question for the SAN: How is buffer latency measured? When you see 36 MB of buffer cache, is that shared or per port? So 36 MB would be 768kb or 36MB per port? With 3 to 6 servers how much buffer cache do you really need? What else should I be looking at? Our application will be heavily using HTML5 websockets (high number of persistent connections). The amount of data being sent is small; Data sent between client <- server isn't broadcasted (not a chat/IM service). We will be doing some database reporting too (csv export, sums, some joins). We are a small business and on a budget. We'd probably only be able to spend no more than $20k on switches total (2 or 4).

    Read the article

  • How to make safe frequent DataSource switches for AbstractRoutingDataSource?

    - by serg555
    I implemented Dynamic DataSource Routing for Spring+Hibernate according to this article. I have several databases with same structure and I need to select which db will run each specific query. Everything works fine on localhost, but I am worrying about how this will hold up in real web site environment. They are using some static context holder to determine which datasource to use: public class CustomerContextHolder { private static final ThreadLocal<CustomerType> contextHolder = new ThreadLocal<CustomerType>(); public static void setCustomerType(CustomerType customerType) { Assert.notNull(customerType, "customerType cannot be null"); contextHolder.set(customerType); } public static CustomerType getCustomerType() { return (CustomerType) contextHolder.get(); } public static void clearCustomerType() { contextHolder.remove(); } } It is wrapped inside some ThreadLocal container, but what exactly does that mean? What will happen when two web requests call this piece of code in parallel: CustomerContextHolder.setCustomerType(CustomerType.GOLD); //<another user will switch customer type here to CustomerType.SILVER in another request> List<Item> goldItems = catalog.getItems(); Is every web request wrapped into its own thread in Spring MVC? Will CustomerContextHolder.setCustomerType() changes be visible to other web users? My controllers have synchronizeOnSession=true. How to make sure that nobody else will switch datasource until I run required query for current user? Thanks.

    Read the article

  • Shall the website switches language based on IP address or browser language?

    - by SuperRomia
    Geo-location has been using most by Websites to redirection, but I have found that several IP addresses locate a country which has using several languages. Meantime, some users prefer to using the language setup in their system. For example, a person from United States goes to Japan and using the Internet connection from there to surf Website, but the Website redirects him to Japanese language. So, shall I giving the web user choice to select the language detect on their browser or force them to the website detected by IP address?

    Read the article

  • How long is the time frame between context switches on Windows?

    - by mattcodes
    Reading CLR via C# 2.0 (I dont have 3.0 with me at the moment) Is this still the case: If there is only one CPU in a computer, only one thread can run at any one time. Windows has to keep track of the thread objects, and every so often, Windows has to decide which thread to schedule next to go to the CPU. This is additional code that has to execute once every 20 milliseconds or so. When Windows makes a CPU stop executing one thread's code and start executing another thread's code, we call this a context switch. A context switch is fairly expensive because the operating system has to: So circa CLR via C# 2.0 lets say we are on Pentium 4 2.4ghz 1 core non-HT, XP. Every 20 milliseconds? Where a CLR thread or Java thread is mapped to an OS thread only a maximum of 50 threads per second may get a chance to to run? I've read that context switching is very fast in mircoseconds here on SO, but how often roughly (magnitude style guesses) will say a modest 5 year old server Windows 2003 Pentium Xeon single core give the OS the opportunity to context switch? 20ms in the right area? I dont need exact figures I just want to be sure that's in the right area, seems rather long to me.

    Read the article

facebook twitter digg google delicious technorati stumbleupon myspace wordpress linkedin gmail igoogle windows live tumblr viadeo yahoo buzz yahoo mail yahoo bookmarks favorites email print

< Previous Page | 1 2 3 4 5 6 7 8 9 10 11 12  | Next Page >