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  • My wireless network slows down every 7.5 minutes when my desktop is switched on

    - by Dog Ears
    My network has lag spikes lasting for a few seconds every 7.5 mins. The spikes also effect any other computer connected connected to my wirless router at the time. My wife has to connect her laptop via a cable to prevent the lag causing problems when she's VPNing into her work. If I switch my PC off the problem goes away! I've got an Edimax 7728ln 802.11n wireless card and Speedtouch 585v7 (I'm with Be) I've Tried... Updated the drivers from Edimax website: 2.0.3.0 (it does say 3.0.2.0 in devices properties though) WLAN Optimizer doesn't seem to be helping What can I do?

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  • How can I access my desktop computer from my Android phone?

    - by Qurben
    Is it possible to access a computer connected to the internet through an Android phone? (the internet goes through the phone by tethering) I want to use ssh to connect to the computer (from a different computer in the same network), but I am not able to access the computer. Is it possible to portforward, use some kind of transparent proxy or to use DMZ? My phone is rooted and I have Cyanogenmod installed and I can use iptables. EDIT: The changed title completely changed the question! My setup is the following: I have an android phone connected to a computer through the usb cable tethering internet from the phone, I wanted to ssh into the computer behind the android phone from another computer in the same network as the android phone. This was not possible, because the android phone creates a separate network for the connected computer, effectively shielding it from any incoming signals. It turned out to be quite simple to fix by just using iptables.

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  • Cannot access apache webserver running on home network from internet.

    - by user60382
    I am trying to setup apache web server in my home network. I followed the instructions found at http://www.boutell.com/newfaq/creating/hostmyown.html. I have a d-link dir-601 router with a cable internet connection. I am able to connect to the web server from my LAN using the url pointing to my server's ip 192.168.0.103 in the web browser. but when I am trying to browse the same with my phone on 3G network, I get a message "server cannot be found". My Public IP starts with 61.xx.xxx.xxx and my router has an IP of 192.168.0.1 Could anyone please help me in figuring out the isuue. Thanks in advance.

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  • Using a BTHomeHub as a wireless booster

    - by Ploo
    I currently have a BT HomeHub downstairs but the wireless signal isnt strong enough on the second floor. I have an old BT HomeHub from the previous contract that I wanted to set up upstairs. I currently have an ethernet cable leading up into the old router. I then took my laptop and plugged it into the old router in hopes of configuring it but when I cannot reach api.home which is the address of the router. I cannot connect to the router wirelessly either since the password was changed and I'd have to change it through config. At this point I am completely stumped, any ideas?

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  • Single PC Satellite Office Firewall

    - by Carl
    We are setting up a small, single PC office about 200 miles away. We plan on getting a cable internet connection but need some advice on a sufficient firewall. We would like to keep it under $100 if possible. 2 options we are considering are: Cisco RVS4000 (got some bad reviews) Linksys WRT120N (running DD-WRT) We need the ability for VPN but other than that we don't need anything special. We just want to keep that PC as safe as possible but easily maintainable because most work will be done remotely. What suggestions or solutions can you recommend for this application?

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  • How can I automatically switch audio to my speakers when my TV-as-2nd-monitor is not in use?

    - by Michael McGowan
    I have a normal LCD monitor as my primary monitor and an HD LCD television as a 2nd monitor (connected through HDMI). I also have a set of normal speakers for the computer (a Windows 7 machine) that I previously used (before I was using the TV as a 2nd monitor). When I am using the TV as a 2nd monitor, I would like audio to come from it. However, I'm oftentimes using the TV as a TV, in which case I would like the audio from my computer to come from my speakers. Is there any way to accomplish this? It seems that if I have the TV set up as the default audio, then even if I turn the TV off (or, more likely, to the input from my cable box), then the audio still goes through that rather than my speakers. Is there a solution that does not require me to manually change the settings every time I want to switch contexts?

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  • My Computer will not turn on?

    - by user269120
    I recently built a gaming pc. It was working fine before the following events: I installed a graphics card driver update then: in windows it said that the user experience index needed to be refreshed, so i started the test and somewhere in the middle of the test my pc just switched off. No shutting down just stopped. Now it won't turn back on. I have checked its plugged in and the switch on psu is down, i tried a different power cable and i checked all the connections. When i press the power button nothing happens, no fans no lights no post beep. Computer Parts: Motherboard: Gigabyte GA78LMT-USB3 CPU: AMD FX-6350 @ 3.9 Ghz RAM: 2x4gb Crucial Ballistix Sport Power Supply: Tesla 750w psu Graphics card: XFX Radeon 7870 DD Case: CiT Vantage R Gaming Case Hard Drive: 2TB Western Digital Caviar Green Please help me, this computer is only a week old since i built it. All anwsers are appreciated :)

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  • How to enable Integrated Load Balancing in Windows 8

    - by intodevelopment
    One of the cool new features many sites mention is "Integrated Load Balancing" in Windows 8. It is supposed to do the following: If you have multiple active network connections, Windows 8 will intelligently balance the network traffic between them for performance Source: Short: Some of what Microsoft didn’t show of Windows 8 I would love to see this feature in action. I am connected to a WiFi access point and to a different network by cable. Yet I don't see the operating system 'intelligently' balance the network load when for instance downloading multiple files. Is there any way to enable it or should I adjust my expectations?

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  • Combine WLAN with LAN

    - by fiatux
    I have D-link DSL 2750U wireless router. My PC and notebook are connected to router by Wi-Fi. They can share files or ping each other. I have a network storage unit plugged into router by an ethernet cable. Any of the computers cannot reach that storage unit or ping it. I guess my router isolates LAN network from WLAN network. Is there a way to combine them and get the router treat all devices connected to router in a single network? Thanks.

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  • Computer restarts infinitely after Bios/Motherboard screen

    - by user13176
    Like every morning I turn on my computer (which is kinda new and only couple months old) and I never had any issue with it until now. It starts booting, shows that very first screen which has some motherboard picture and stuff and then it show which buttons to press to enter BIOS and etc. Then it suddenly restarted and after that just kept restarting every 3-5 seconds forever. What could that be? I unplugged power cable, checked all the cables, moved a case, it had some wires stuck under it, blew some dust (but didn't open the case yet) and I tried to boot again and it booted successfully and I am writing this issue now. My specs: i3-3220 3.30Ghz 8GB DDR3 RAM 1TB HDD GeForce GTX 650 Windows 8 x64 I also recently upgraded my security software (that's the most recent thing I did) and it includes ZoneAlarm firewall, Comodo Antivirus and Spybot Search & Destroy. But maybe it doesn't have anything to do with this. Cheers

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  • messed System Files on Mac PPC

    - by glider
    My buddy deleted her System folder from her PPC Mac wanting to get that space for something else. She copied it first in another drive (she had partitioned disk).She haven't emptied the Trash Bin yet. The screen just froze right after she moved the folder to Trash. We tried to use the install disk but even if we try Power-C on booting,it would try to continue,display the apple logo page then quickly follow it with black screen filled with dumps of hex codes and "We are hanging here..." We have a Windows-based PC that we tried to connect using ethernet cable but we can't find her computer from there. What should we do now???

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  • How does communication between 2 computers in a single network happen?

    - by learner
    Lets say I and my friend connect our computers with a LAN cable. I ping my friend with his IP address. How does it work? Since we are in the same network, we don't even need IP addresses, do we? Isn't IP addressing only relevant in case of inter-network communication? What will the ping command do with his IP address? How will it eventually find his physical address (NIC address)? (no ARP here, because that would involve a router at the edge of the network, which doesn't apply here). Am I wrong somewhere?

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  • Is it worth having SATA 6GB/s cables? [duplicate]

    - by zyboxenterprises
    This question already has an answer here: Are all SATA cables compatible with SATA 3? 2 answers I've just received some SATA 3 6GB/s cables that I ordered last week, and it struck me how ordinary they look when compared to normal standard SATA cables. My PCI-E SATA3 card is yet to arrive. My question is, would a standard SATA cable have the same transfer speeds as my SATA 3 6GB/s cables? Question is similar to this one, but however it doesn't have an answer. This question isn't asking 'are all SATA cables compatible with SATA 3', it's asking whether SATA 2 and SATA 3 transfer speeds are the same.

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  • Social Media event Bandwidth requirements

    - by Bob G
    I have an one day event in July 2012, hosting 250 attendees for a social media event. We will be uploading live video to a website, allowing the press to access the web, and some vendors will be showing off their web sites for clients and visitors. The staff will need access for uploading files and information as needed. We had the event last year and tried a cable modem brought in with 2x2 megs just for the streaming video which worked well. I had 4 wireless hot spots, rented from a company 1.5 mbps x 780 kbps, which was were a complete failure. I was assured the 4 hot spots would be enough, but they did not work. What would be the proper way to get the bandwidth required to make the one day event successful? The setting is a Private Country Club where running cables everywhere is very tough.

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  • Computer won't start when connecting SATA HDD

    - by vlad
    I just bough a new HDD some time ago and recently i bought another SATA cable to have both HDDs connected at the same time, to transfer all the files from the older one to the newer. When i connected both of them, the computer started working, i tapped F2 to go to bios to make sure it was detected, and then after 5-10 seconds the computer instantly shut down. After this incident, my computer won't start at all when connecting the SATA power supply to the old HDD. If i connect only my new drive, it works without any problem. If i connect only my old drive, or both the old drive and the new one, and then push on the power button, the cpu fan simply rotates about 5 degrees and then stops.. and that's it, the computer doesn't start, and no sound from the pc speaker either. Is there any way to recover my files from the old HDD and transfer them to my new one? I do not want to use the old HDD any more, i only need to save all my files.

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  • Connecting Samsung Note 3 to Hitachi CPX3030WN via Samsung MHL 2.0 HD kit , Will there be video output? [on hold]

    - by Monolord's Knight
    I need the video output to projector. but nobody can assure me this may work or not. some says yes some says no.But they have no real experience. Some says an special android app is required for this. Depending on this answer, I will purchase Samsung MHL 2.0 cable . If it wont work it will be no use for me. I don't have a way to change my phone or projector. Just want to know will it work or not. Thanks

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  • Letter to Ballmer: Making Better Consumer Devices

    - by andrewbrust
    Last year, I wrote Steve Ballmer an email, and he was kind enough to write me back.  The email contained a scan of a column I wrote praising Microsoft’s BI strategy.  His reply contained three simple words: “Super nice  thanks.” Well, now I’d like to write to Steve again, in an open letter format, and this time the love may be a bit tougher.  But I’m still super earnest. The past two days have been eventful ones for Microsoft: The company announced the departure of company veterans Robbie Bach and J Allard and the market announced Apple is now besting Microsoft in market capitalization. Plus, announcements were made that make it plain that Ballmer will, in effect, be running Microsoft’s Entertainment & Devices division himself. With that in mind, I’d like to offer my list of a dozen things I think Microsoft’s CEO should do to improve that division’s offerings and, hopefully, its bottom line. So here goes:   1. On Windows Phone 7, Stay the Course The press is teeming with headlines and reader comments proclaiming the death-before-arrival of Windows Phone 7.  That’s plain silly.  You’ve got the makings of a great and unique SmartPhone platform, and you’re the only company (even considering RIM) that can offer full fidelity Exchange integration, not to mention implementing Office on the device.  Let the existing team finish this puppy and ship it. And then have them pump out a few updates, over-the-air, quickly.  Show them that Google Android’s not the only product that can do good, rapid dot releases. And another thing: make sure your OEMs’ devices have flawless touch screens.  If they don’t, then you shouldn’t certify them for delivery to customers.  Period. Oh, and kill the Kin, quietly.  It was DOA, and you know it.   2. Move Media Center to the Xbox Platform Media Center is, at its core, a good product.  But delivering a media distribution and DVR platform on a sophisticated PC operating system like Windows 7 just creates too many moving parts.  Xbox already functions as the best Media Center extender device – it should actually be the hub as well. Media Center is mostly based on .NET code – and XNA is a .NET environment for Xbox – find a way to bridge that small gap and make Media Center a joy to work with instead of a frustration.  Beating Apple TV out of this sub-market is the lowest hanging fruit on the tree (goofy pun, but it’s true).   3. Integrate Media Center with Mediaroom, or Kill the Latter You have two media products with almost identical names.  One is for standalone DVRs and the other is for IPTV cable set tops with DVR capabilities.  Can we merge these please?  My previous request of putting Media Center on Xbox would seem to tie into this nicely, since you’ve announced plans to do that with Mediaroom already.   4. Fix the Red Ring of Death People love the Xbox, but they really don’t love sending their consoles back every 18-24 months, when they get a bunch of red lights flashing on power up.  You’ve handled this defect about as gracefully as possible, but it’s been around for a long time now and it doesn’t seem to be fixed yet.  You can do better.  In fact, you must do better, or you insult your customers.   5. Add Blu Ray to Xbox I know, streaming movies are the future; physical media is legacy technology.  So if that’s true, why did you back HD DVD so hard?  You know why: for now, the film studios won’t allow a large selection of new release, HD, surround sound content be distributed on any medium other than Blu Ray or cable pay per view/on-demand.  Don’t you want home theater buffs to see the Xbox as a fantastic device for their rigs?  Don’t you want to put PlayStation 3 out of its misery?  And if you follow my suggestions above (move Media Center to the Xbox and fix the Red Ring problem), you’d have it all sewn up.  Do I think Blu Ray functionality will move a lot of units?  No.  Do I think that it would move more units with desperately needed influential home theater consumers?  You bet.  And you might sell more ZunePass subscriptions in the process. But while you’re at it, make the fan quieter, please.   6. Make More of Windows Home Server Home Server is a fantastic product.  And for reasons unknown to me, it seems like you’re letting it languish.  Development of the add-in ecosystem seems underfunded.  WHS’ unparalleled ease of use and reliability for home PC backup (and emergency restores) goes unsung.  Product cycles are slow.  Support for your OEMs, who are doing great work, especially in the green space with Atom CPUs, seems lacking.  You’ve married a trophy girl and you keep her cloistered at home!  That’s cruel, unusual and, um, incredibly ill-advised.  Make use of this ace card, and while you’re at it, give it real integration with Media Center.  The integration thus far proof-of-concept quality.  You should go way past that – both products will benefit immeasurably.   7. Set Up a Partner Platform for Custom Installers There’s a whole sub-industry of companies that install, integrate and configure home theater, security and connected home products.  They have an industry group. They are influential in the high-end of the consumer electronics industry, and so are their customers.  They love Media Center and they love Windows Home Server.  But I have talked to several of them at the Consumer Electronics Show and they tell me you don’t love them.  They find it very difficult to do business with Microsoft, even though they want nothing more than to sell and evangelize your platform.  This is a travesty.  Please fix it.  Get Allison Watson and the Microsoft Partner Network on board and have her hire someone who knows how to run a channel program for consumer electronics companies.  Problem solved.  Markets expanded.   8. Make Your Own Hardware In other areas, I know you love your partners.  I help run one, so I appreciate that.  But when it came to Xbox and Zune you built them it yourself (albeit on a contract basis, which is fine).  Windows Phone 7 has a chance to work as an OEM play, but it would work better if you produced the devices.  At least consider building a reference device that sells alongside your OEMs’ offerings.  That’s what Google did with the Nexxus One.  And while that phone was not itself a big seller, it catalyzed two wonderful things : (1) a quality bar was set and (2) partners exceeded it.  Before the Nexxus One, the best Android handset out there was the Motorola Droid. The Nexxus One was better, and the HTC Droid Incredible and Evo 4G are now even better than Google’s phone, which is why Verizon and Sprint decided not to carry it.  Imagine if all Windows Phone 6.x devices were on par with the HTC HD2.  I tend to believe you’d have a lot bigger market share than you do now.   9. Continue with Your Retail Initiative From what I hear, it sounds like it’s going well.  And this goes right along with making your own hardware.  When you build it, they will come.  And then it makes the likes of Best Buy and Staples do better.   10. Make an Acquisition (or Two) TiVo and/or Moxi look ripe for the picking.  With their ability to build stuff people love and your ability to run a business, you might just have something.  But do a better job than you did when you bought Danger.  Buy the ideas, not just the customers, eh?   11. Make Beautiful Stuff You’ve heard this one before, I know.  But I have some head-shrinking advice on this one.  You know that Apple obsesses over its industrial design.  You know that appeals to consumers.  But it seems you think doing so is Apple’s game exclusively and so you shouldn’t even try.  Bull dinky.  Come to New York and visit the Museum of Modern Art’s Architecture and Design gallery.  You’ll see that lots of companies and product categories have had very high design value well before Apple existed.  You can do this, and the Zune HD was a great start.  Now run with that.  Find those negative voices in your head that are telling you that you can’t and shut them up.  For good.   12. Burst the Bubble Some of the products you’ve built seem like they were conceived in a bizarro world.  That would appear to be the result of groupthink.  You must do better.  And there’s lots of people willing to advise you.  This includes just about everyone in the Regional Director program, and probably a bunch of MVPs.  Heck, I bet the guys at Engadget could help out too.  Imagine if you let them see the Kin before it shipped.  Talk to high-end gear consumers.  Talk to Best Buy and CostCo customers too.   Signing Off I hope this was of value to you.  As I wrote this I kept telling myself how obvious, even trite, some of these pieces of advice were and then, because of that, doubting they’d really help.  But I decided that they must not be obvious to Microsoft.  Sometimes when you get wrapped up in stuff, it’s hard to clear your head.  I think my head’s pretty clear here though (I’m wrapped up in other stuff), so maybe my perspective can help.  If not, well, then, I guess they all can’t be super nice.

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  • The Other "C" in CRM

    - by Brian Dayton
    Folks who know me know that I rarely, if ever, talk politics. And I never talk politicians. Having grown up in a household with one parent leaning left and the other leaning to the right it was the best way to keep the peace. This isn't about politics. It's about "constituents" and the need to improve the services and service levels for people--at the city, county, state/province, etc. level all the way up to national governments. As a citizen and tax payer it's also important to me that these services be provided at a reasonable cost. If there's a better and more efficient way to do something then it's my hope that a public sector organization takes advantage of technology the same way private sector companies do. Social services organizations have a complex job. They provide the services that people need, from healthcare and children's assistance to helping people find jobs. But many of these organizations are still managing these processes manually or outdated, home-grown applications that could have been written up to 30 years ago. A lot has changed in technology. On the (this is as political as I'm going to get) political front, stakeholders like you and me are expecting greater transparency on where and how funds are spent. I'll admit that most of the time, when I think about CRM systems, I think about my experience as a customer of my bank, utilities company or cable operator. But now that I'm older, have children and a house--I find myself interacting more and more with agencies and services organizations. My experiences are sometimes good and sometimes not so good. Along those lines, last week's announcement of Siebel CRM 8.2 for Public Sector caught my eye. You may not work in the public sector, but you are a constituent of some--actually a lot--of public sector organizations. I don't know which CRM systems city and county utilize but I'm going to start paying closer attention.

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  • How to mount a blu-ray drive?

    - by Stephan Schielke
    Maybe it is for the best to close this question. This has nothing to do with a bluray drive in general anymore. Probably a hardware defect. I will try to test it with a windows system and different cables again... Thx so far. I have a bluray/dvd/cdrom drive with SATA. Ubuntu wont find it under /dev/sd wodim --devices wodim: Overview of accessible drives (1 found) : ------------------------------------------------------------------------- 0 dev='/dev/sg2' rwrw-- : 'HL-DT-ST' 'BDDVDRW CH08LS10' ------------------------------------------------------------------------- cdrecord -scanbus scsibus2: 2,0,0 200) 'HL-DT-ST' 'BDDVDRW CH08LS10' '2.00' Removable CD-ROM fdisk dont even lists it. Ubuntu only automounts blank DVDs, but neither CDROM nor Blurays. I also changed the sata slot, sata cable and the power cable. The drive works with a windows system. This happens when I try to mount: sudo mount -t auto /dev/scd0 /media/bluray mount: you must specify the filesystem type I tried all filesystems there are. I also installed makemkv. It finds the drive but not the disc. Here is my /dev ls -al /dev total 12 drwxr-xr-x 17 root root 4420 2011-11-25 19:36 . drwxr-xr-x 28 root root 4096 2011-11-25 07:12 .. crw------- 1 root root 10, 235 2011-11-25 19:28 autofs -rw-r--r-- 1 root root 630 2011-11-25 19:28 .blkid.tab -rw-r--r-- 1 root root 630 2011-11-25 19:28 .blkid.tab.old drwxr-xr-x 2 root root 700 2011-11-25 19:27 block drwxr-xr-x 2 root root 100 2011-11-25 19:27 bsg crw------- 1 root root 10, 234 2011-11-25 19:28 btrfs-control drwxr-xr-x 3 root root 60 2011-11-25 19:27 bus drwxr-xr-x 2 root root 3820 2011-11-25 19:28 char crw------- 1 root root 5, 1 2011-11-25 19:28 console lrwxrwxrwx 1 root root 11 2011-11-25 19:28 core -> /proc/kcore drwxr-xr-x 2 root root 60 2011-11-25 19:28 cpu crw------- 1 root root 10, 60 2011-11-25 19:28 cpu_dma_latency drwxr-xr-x 7 root root 140 2011-11-25 19:27 disk crw------- 1 root root 10, 61 2011-11-25 19:28 ecryptfs crw-rw---- 1 root video 29, 0 2011-11-25 19:28 fb0 lrwxrwxrwx 1 root root 13 2011-11-25 19:28 fd -> /proc/self/fd crw-rw-rw- 1 root root 1, 7 2011-11-25 19:28 full crw-rw-rw- 1 root fuse 10, 229 2011-11-25 19:28 fuse crw------- 1 root root 251, 0 2011-11-25 19:28 hidraw0 crw------- 1 root root 251, 1 2011-11-25 19:28 hidraw1 crw------- 1 root root 10, 228 2011-11-25 19:28 hpet lrwxrwxrwx 1 root root 14 2011-11-25 19:27 .initramfs -> /run/initramfs drwxr-xr-x 4 root root 220 2011-11-25 19:28 input crw------- 1 root root 1, 11 2011-11-25 19:28 kmsg srw-rw-rw- 1 root root 0 2011-11-25 19:28 log brw-rw---- 1 root disk 7, 0 2011-11-25 19:28 loop0 brw-rw---- 1 root disk 7, 1 2011-11-25 19:28 loop1 brw-rw---- 1 root disk 7, 2 2011-11-25 19:28 loop2 brw-rw---- 1 root disk 7, 3 2011-11-25 19:28 loop3 brw-rw---- 1 root disk 7, 4 2011-11-25 19:28 loop4 brw-rw---- 1 root disk 7, 5 2011-11-25 19:28 loop5 brw-rw---- 1 root disk 7, 6 2011-11-25 19:28 loop6 brw-rw---- 1 root disk 7, 7 2011-11-25 19:28 loop7 drwxr-xr-x 2 root root 60 2011-11-25 19:27 mapper crw------- 1 root root 10, 227 2011-11-25 19:28 mcelog crw-r----- 1 root kmem 1, 1 2011-11-25 19:28 mem drwxr-xr-x 2 root root 60 2011-11-25 19:27 net crw------- 1 root root 10, 59 2011-11-25 19:28 network_latency crw------- 1 root root 10, 58 2011-11-25 19:28 network_throughput crw-rw-rw- 1 root root 1, 3 2011-11-25 19:28 null crw-rw-rw- 1 root root 195, 0 2011-11-25 19:28 nvidia0 crw-rw-rw- 1 root root 195, 255 2011-11-25 19:28 nvidiactl crw------- 1 root root 1, 12 2011-11-25 19:28 oldmem crw-r----- 1 root kmem 1, 4 2011-11-25 19:28 port crw------- 1 root root 108, 0 2011-11-25 19:28 ppp crw------- 1 root root 10, 1 2011-11-25 19:28 psaux crw-rw-rw- 1 root tty 5, 2 2011-11-25 20:00 ptmx drwxr-xr-x 2 root root 0 2011-11-25 19:27 pts brw-rw---- 1 root disk 1, 0 2011-11-25 19:28 ram0 brw-rw---- 1 root disk 1, 1 2011-11-25 19:28 ram1 brw-rw---- 1 root disk 1, 10 2011-11-25 19:28 ram10 brw-rw---- 1 root disk 1, 11 2011-11-25 19:28 ram11 brw-rw---- 1 root disk 1, 12 2011-11-25 19:28 ram12 brw-rw---- 1 root disk 1, 13 2011-11-25 19:28 ram13 brw-rw---- 1 root disk 1, 14 2011-11-25 19:28 ram14 brw-rw---- 1 root disk 1, 15 2011-11-25 19:28 ram15 brw-rw---- 1 root disk 1, 2 2011-11-25 19:28 ram2 brw-rw---- 1 root disk 1, 3 2011-11-25 19:28 ram3 brw-rw---- 1 root disk 1, 4 2011-11-25 19:28 ram4 brw-rw---- 1 root disk 1, 5 2011-11-25 19:28 ram5 brw-rw---- 1 root disk 1, 6 2011-11-25 19:28 ram6 brw-rw---- 1 root disk 1, 7 2011-11-25 19:28 ram7 brw-rw---- 1 root disk 1, 8 2011-11-25 19:28 ram8 brw-rw---- 1 root disk 1, 9 2011-11-25 19:28 ram9 crw-rw-rw- 1 root root 1, 8 2011-11-25 19:28 random crw-rw-r--+ 1 root root 10, 62 2011-11-25 19:28 rfkill lrwxrwxrwx 1 root root 4 2011-11-25 19:28 rtc -> rtc0 crw------- 1 root root 254, 0 2011-11-25 19:28 rtc0 lrwxrwxrwx 1 root root 3 2011-11-25 19:38 scd0 -> sr0 brw-rw---- 1 root disk 8, 0 2011-11-25 19:28 sda brw-rw---- 1 root disk 8, 1 2011-11-25 19:28 sda1 brw-rw---- 1 root disk 8, 2 2011-11-25 19:28 sda2 brw-rw---- 1 root disk 8, 3 2011-11-25 19:28 sda3 brw-rw---- 1 root disk 8, 5 2011-11-25 19:28 sda5 brw-rw---- 1 root disk 8, 6 2011-11-25 19:28 sda6 brw-rw---- 1 root disk 8, 16 2011-11-25 19:28 sdb brw-rw---- 1 root disk 8, 17 2011-11-25 19:28 sdb1 crw-rw---- 1 root disk 21, 0 2011-11-25 19:28 sg0 crw-rw---- 1 root disk 21, 1 2011-11-25 19:28 sg1 crw-rw----+ 1 root cdrom 21, 2 2011-11-25 19:28 sg2 lrwxrwxrwx 1 root root 8 2011-11-25 19:28 shm -> /run/shm crw------- 1 root root 10, 231 2011-11-25 19:28 snapshot drwxr-xr-x 4 root root 280 2011-11-25 19:28 snd brw-rw----+ 1 root cdrom 11, 0 2011-11-25 19:38 sr0 lrwxrwxrwx 1 root root 15 2011-11-25 19:28 stderr -> /proc/self/fd/2 lrwxrwxrwx 1 root root 15 2011-11-25 19:28 stdin -> /proc/self/fd/0 lrwxrwxrwx 1 root root 15 2011-11-25 19:28 stdout -> /proc/self/fd/1 crw-rw-rw- 1 root tty 5, 0 2011-11-25 19:35 tty crw--w---- 1 root tty 4, 0 2011-11-25 19:28 tty0 crw------- 1 root root 4, 1 2011-11-25 19:28 tty1 crw--w---- 1 root tty 4, 10 2011-11-25 19:28 tty10 crw--w---- 1 root tty 4, 11 2011-11-25 19:28 tty11 crw--w---- 1 root tty 4, 12 2011-11-25 19:28 tty12 crw--w---- 1 root tty 4, 13 2011-11-25 19:28 tty13 crw--w---- 1 root tty 4, 14 2011-11-25 19:28 tty14 crw--w---- 1 root tty 4, 15 2011-11-25 19:28 tty15 crw--w---- 1 root tty 4, 16 2011-11-25 19:28 tty16 crw--w---- 1 root tty 4, 17 2011-11-25 19:28 tty17 crw--w---- 1 root tty 4, 18 2011-11-25 19:28 tty18 crw--w---- 1 root tty 4, 19 2011-11-25 19:28 tty19 crw------- 1 root root 4, 2 2011-11-25 19:28 tty2 crw--w---- 1 root tty 4, 20 2011-11-25 19:28 tty20 crw--w---- 1 root tty 4, 21 2011-11-25 19:28 tty21 crw--w---- 1 root tty 4, 22 2011-11-25 19:28 tty22 crw--w---- 1 root tty 4, 23 2011-11-25 19:28 tty23 crw--w---- 1 root tty 4, 24 2011-11-25 19:28 tty24 crw--w---- 1 root tty 4, 25 2011-11-25 19:28 tty25 crw--w---- 1 root tty 4, 26 2011-11-25 19:28 tty26 crw--w---- 1 root tty 4, 27 2011-11-25 19:28 tty27 crw--w---- 1 root tty 4, 28 2011-11-25 19:28 tty28 crw--w---- 1 root tty 4, 29 2011-11-25 19:28 tty29 crw------- 1 root root 4, 3 2011-11-25 19:28 tty3 crw--w---- 1 root tty 4, 30 2011-11-25 19:28 tty30 crw--w---- 1 root tty 4, 31 2011-11-25 19:28 tty31 crw--w---- 1 root tty 4, 32 2011-11-25 19:28 tty32 crw--w---- 1 root tty 4, 33 2011-11-25 19:28 tty33 crw--w---- 1 root tty 4, 34 2011-11-25 19:28 tty34 crw--w---- 1 root tty 4, 35 2011-11-25 19:28 tty35 crw--w---- 1 root tty 4, 36 2011-11-25 19:28 tty36 crw--w---- 1 root tty 4, 37 2011-11-25 19:28 tty37 crw--w---- 1 root tty 4, 38 2011-11-25 19:28 tty38 crw--w---- 1 root tty 4, 39 2011-11-25 19:28 tty39 crw------- 1 root root 4, 4 2011-11-25 19:28 tty4 crw--w---- 1 root tty 4, 40 2011-11-25 19:28 tty40 crw--w---- 1 root tty 4, 41 2011-11-25 19:28 tty41 crw--w---- 1 root tty 4, 42 2011-11-25 19:28 tty42 crw--w---- 1 root tty 4, 43 2011-11-25 19:28 tty43 crw--w---- 1 root tty 4, 44 2011-11-25 19:28 tty44 crw--w---- 1 root tty 4, 45 2011-11-25 19:28 tty45 crw--w---- 1 root tty 4, 46 2011-11-25 19:28 tty46 crw--w---- 1 root tty 4, 47 2011-11-25 19:28 tty47 crw--w---- 1 root tty 4, 48 2011-11-25 19:28 tty48 crw--w---- 1 root tty 4, 49 2011-11-25 19:28 tty49 crw------- 1 root root 4, 5 2011-11-25 19:28 tty5 crw--w---- 1 root tty 4, 50 2011-11-25 19:28 tty50 crw--w---- 1 root tty 4, 51 2011-11-25 19:28 tty51 crw--w---- 1 root tty 4, 52 2011-11-25 19:28 tty52 crw--w---- 1 root tty 4, 53 2011-11-25 19:28 tty53 crw--w---- 1 root tty 4, 54 2011-11-25 19:28 tty54 crw--w---- 1 root tty 4, 55 2011-11-25 19:28 tty55 crw--w---- 1 root tty 4, 56 2011-11-25 19:28 tty56 crw--w---- 1 root tty 4, 57 2011-11-25 19:28 tty57 crw--w---- 1 root tty 4, 58 2011-11-25 19:28 tty58 crw--w---- 1 root tty 4, 59 2011-11-25 19:28 tty59 crw------- 1 root root 4, 6 2011-11-25 19:28 tty6 crw--w---- 1 root tty 4, 60 2011-11-25 19:28 tty60 crw--w---- 1 root tty 4, 61 2011-11-25 19:28 tty61 crw--w---- 1 root tty 4, 62 2011-11-25 19:28 tty62 crw--w---- 1 root tty 4, 63 2011-11-25 19:28 tty63 crw--w---- 1 root tty 4, 7 2011-11-25 19:28 tty7 crw--w---- 1 root tty 4, 8 2011-11-25 19:28 tty8 crw--w---- 1 root tty 4, 9 2011-11-25 19:28 tty9 crw------- 1 root root 5, 3 2011-11-25 19:28 ttyprintk crw-rw---- 1 root dialout 4, 64 2011-11-25 19:28 ttyS0 crw-rw---- 1 root dialout 4, 65 2011-11-25 19:28 ttyS1 crw-rw---- 1 root dialout 4, 74 2011-11-25 19:28 ttyS10 crw-rw---- 1 root dialout 4, 75 2011-11-25 19:28 ttyS11 crw-rw---- 1 root dialout 4, 76 2011-11-25 19:28 ttyS12 crw-rw---- 1 root dialout 4, 77 2011-11-25 19:28 ttyS13 crw-rw---- 1 root dialout 4, 78 2011-11-25 19:28 ttyS14 crw-rw---- 1 root dialout 4, 79 2011-11-25 19:28 ttyS15 crw-rw---- 1 root dialout 4, 80 2011-11-25 19:28 ttyS16 crw-rw---- 1 root dialout 4, 81 2011-11-25 19:28 ttyS17 crw-rw---- 1 root dialout 4, 82 2011-11-25 19:28 ttyS18 crw-rw---- 1 root dialout 4, 83 2011-11-25 19:28 ttyS19 crw-rw---- 1 root dialout 4, 66 2011-11-25 19:28 ttyS2 crw-rw---- 1 root dialout 4, 84 2011-11-25 19:28 ttyS20 crw-rw---- 1 root dialout 4, 85 2011-11-25 19:28 ttyS21 crw-rw---- 1 root dialout 4, 86 2011-11-25 19:28 ttyS22 crw-rw---- 1 root dialout 4, 87 2011-11-25 19:28 ttyS23 crw-rw---- 1 root dialout 4, 88 2011-11-25 19:28 ttyS24 crw-rw---- 1 root dialout 4, 89 2011-11-25 19:28 ttyS25 crw-rw---- 1 root dialout 4, 90 2011-11-25 19:28 ttyS26 crw-rw---- 1 root dialout 4, 91 2011-11-25 19:28 ttyS27 crw-rw---- 1 root dialout 4, 92 2011-11-25 19:28 ttyS28 crw-rw---- 1 root dialout 4, 93 2011-11-25 19:28 ttyS29 crw-rw---- 1 root dialout 4, 67 2011-11-25 19:28 ttyS3 crw-rw---- 1 root dialout 4, 94 2011-11-25 19:28 ttyS30 crw-rw---- 1 root dialout 4, 95 2011-11-25 19:28 ttyS31 crw-rw---- 1 root dialout 4, 68 2011-11-25 19:28 ttyS4 crw-rw---- 1 root dialout 4, 69 2011-11-25 19:28 ttyS5 crw-rw---- 1 root dialout 4, 70 2011-11-25 19:28 ttyS6 crw-rw---- 1 root dialout 4, 71 2011-11-25 19:28 ttyS7 crw-rw---- 1 root dialout 4, 72 2011-11-25 19:28 ttyS8 crw-rw---- 1 root dialout 4, 73 2011-11-25 19:28 ttyS9 d rwxr-xr-x 3 root root 60 2011-11-25 19:28 .udev crw-r----- 1 root root 10, 223 2011-11-25 19:28 uinput crw-rw-rw- 1 root root 1, 9 2011-11-25 19:28 urandom drwxr-xr-x 2 root root 60 2011-11-25 19:27 usb crw------- 1 root root 252, 0 2011-11-25 19:28 usbmon0 crw------- 1 root root 252, 1 2011-11-25 19:28 usbmon1 crw------- 1 root root 252, 2 2011-11-25 19:28 usbmon2 crw------- 1 root root 252, 3 2011-11-25 19:28 usbmon3 crw------- 1 root root 252, 4 2011-11-25 19:28 usbmon4 crw------- 1 root root 252, 5 2011-11-25 19:28 usbmon5 crw------- 1 root root 252, 6 2011-11-25 19:28 usbmon6 crw------- 1 root root 252, 7 2011-11-25 19:28 usbmon7 crw------- 1 root root 252, 8 2011-11-25 19:28 usbmon8 drwxr-xr-x 4 root root 80 2011-11-25 19:28 v4l crw------- 1 root root 10, 57 2011-11-25 19:28 vboxdrv crw------- 1 root root 10, 56 2011-11-25 19:28 vboxnetctl drwxr-x--- 4 root vboxusers 80 2011-11-25 19:28 vboxusb crw-rw---- 1 root tty 7, 0 2011-11-25 19:28 vcs crw-rw---- 1 root tty 7, 1 2011-11-25 19:28 vcs1 crw-rw---- 1 root tty 7, 2 2011-11-25 19:28 vcs2 crw-rw---- 1 root tty 7, 3 2011-11-25 19:28 vcs3 crw-rw---- 1 root tty 7, 4 2011-11-25 19:28 vcs4 crw-rw---- 1 root tty 7, 5 2011-11-25 19:28 vcs5 crw-rw---- 1 root tty 7, 6 2011-11-25 19:28 vcs6 crw-rw---- 1 root tty 7, 128 2011-11-25 19:28 vcsa crw-rw---- 1 root tty 7, 129 2011-11-25 19:28 vcsa1 crw-rw---- 1 root tty 7, 130 2011-11-25 19:28 vcsa2 crw-rw---- 1 root tty 7, 131 2011-11-25 19:28 vcsa3 crw-rw---- 1 root tty 7, 132 2011-11-25 19:28 vcsa4 crw-rw---- 1 root tty 7, 133 2011-11-25 19:28 vcsa5 crw-rw---- 1 root tty 7, 134 2011-11-25 19:28 vcsa6 crw------- 1 root root 10, 63 2011-11-25 19:28 vga_arbiter crw-rw----+ 1 root video 81, 0 2011-11-25 19:28 video0 crw-rw-rw- 1 root root 1, 5 2011-11-25 19:28 zero sg_scan -i gives me: sudo sg_scan -i /dev/sg0: scsi0 channel=0 id=0 lun=0 [em] ATA ST31000524NS SN12 [rmb=0 cmdq=0 pqual=0 pdev=0x0] /dev/sg1: scsi0 channel=0 id=1 lun=0 [em] ATA WDC WD15EADS-00S 01.0 [rmb=0 cmdq=0 pqual=0 pdev=0x0] /dev/sg2: scsi2 channel=0 id=0 lun=0 [em] HL-DT-ST BDDVDRW CH08LS10 2.00 [rmb=1 cmdq=0 pqual=0 pdev=0x5] sg_map gives me: /dev/sg0 /dev/sda /dev/sg1 /dev/sdb /dev/sg2 /dev/scd0 lsscsi -l gives me: [0:0:0:0] disk ATA ST31000524NS SN12 /dev/sda state=running queue_depth=1 scsi_level=6 type=0 device_blocked=0 timeout=30 [0:0:1:0] disk ATA WDC WD15EADS-00S 01.0 /dev/sdb state=running queue_depth=1 scsi_level=6 type=0 device_blocked=0 timeout=30 [2:0:0:0] cd/dvd HL-DT-ST BDDVDRW CH08LS10 2.00 /dev/sr0 state=running queue_depth=1 scsi_level=6 type=5 device_blocked=0 timeout=30 my udf mod is: filename: /lib/modules/3.0.0-14-generic/kernel/fs/udf/udf.ko license: GPL description: Universal Disk Format Filesystem author: Ben Fennema srcversion: 6ABDE012374D96B9685B8E5 depends: crc-itu-t vermagic: 3.0.0-14-generic SMP mod_unload modversions Do I need special drivers or mods enabled? Do I need to change some BIOS settings? edit: Somehow I am now able to fire the mount command without any filesystem errors, but now I get: mount: no medium found on /dev/sr0

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  • How to Avoid Your Next 12-Month Science Project

    - by constant
    While most customers immediately understand how the magic of Oracle's Hybrid Columnar Compression, intelligent storage servers and flash memory make Exadata uniquely powerful against home-grown database systems, some people think that Exalogic is nothing more than a bunch of x86 servers, a storage appliance and an InfiniBand (IB) network, built into a single rack. After all, isn't this exactly what the High Performance Computing (HPC) world has been doing for decades? On the surface, this may be true. And some people tried exactly that: They tried to put together their own version of Exalogic, but then they discover there's a lot more to building a system than buying hardware and assembling it together. IT is not Ikea. Why is that so? Could it be there's more going on behind the scenes than merely putting together a bunch of servers, a storage array and an InfiniBand network into a rack? Let's explore some of the special sauce that makes Exalogic unique and un-copyable, so you can save yourself from your next 6- to 12-month science project that distracts you from doing real work that adds value to your company. Engineering Systems is Hard Work! The backbone of Exalogic is its InfiniBand network: 4 times better bandwidth than even 10 Gigabit Ethernet, and only about a tenth of its latency. What a potential for increased scalability and throughput across the middleware and database layers! But InfiniBand is a beast that needs to be tamed: It is true that Exalogic uses a standard, open-source Open Fabrics Enterprise Distribution (OFED) InfiniBand driver stack. Unfortunately, this software has been developed by the HPC community with fastest speed in mind (which is good) but, despite the name, not many other enterprise-class requirements are included (which is less good). Here are some of the improvements that Oracle's InfiniBand development team had to add to the OFED stack to make it enterprise-ready, simply because typical HPC users didn't have the need to implement them: More than 100 bug fixes in the pieces that were not related to the Message Passing Interface Protocol (MPI), which is the protocol that HPC users use most of the time, but which is less useful in the enterprise. Performance optimizations and tuning across the whole IB stack: From Switches, Host Channel Adapters (HCAs) and drivers to low-level protocols, middleware and applications. Yes, even the standard HPC IB stack could be improved in terms of performance. Ethernet over IB (EoIB): Exalogic uses InfiniBand internally to reach high performance, but it needs to play nicely with datacenters around it. That's why Oracle added Ethernet over InfiniBand technology to it that allows for creating many virtual 10GBE adapters inside Exalogic's nodes that are aggregated and connected to Exalogic's IB gateway switches. While this is an open standard, it's up to the vendor to implement it. In this case, Oracle integrated the EoIB stack with Oracle's own IB to 10GBE gateway switches, and made it fully virtualized from the beginning. This means that Exalogic customers can completely rewire their server infrastructure inside the rack without having to physically pull or plug a single cable - a must-have for every cloud deployment. Anybody who wants to match this level of integration would need to add an InfiniBand switch development team to their project. Or just buy Oracle's gateway switches, which are conveniently shipped with a whole server infrastructure attached! IPv6 support for InfiniBand's Sockets Direct Protocol (SDP), Reliable Datagram Sockets (RDS), TCP/IP over IB (IPoIB) and EoIB protocols. Because no IPv6 = not very enterprise-class. HA capability for SDP. High Availability is not a big requirement for HPC, but for enterprise-class application servers it is. Every node in Exalogic's InfiniBand network is connected twice for redundancy. If any cable or port or HCA fails, there's always a replacement link ready to take over. This requires extra magic at the protocol level to work. So in addition to Weblogic's failover capabilities, Oracle implemented IB automatic path migration at the SDP level to avoid unnecessary failover operations at the middleware level. Security, for example spoof-protection. Another feature that is less important for traditional users of InfiniBand, but very important for enterprise customers. InfiniBand Partitioning and Quality-of-Service (QoS): One of the first questions we get from customers about Exalogic is: “How can we implement multi-tenancy?” The answer is to partition your IB network, which effectively creates many networks that work independently and that are protected at the lowest networking layer possible. In addition to that, QoS allows administrators to prioritize traffic flow in multi-tenancy environments so they can keep their service levels where it matters most. Resilient IB Fabric Management: InfiniBand is a self-managing network, so a lot of the magic lies in coming up with the right topology and in teaching the subnet manager how to properly discover and manage the network. Oracle's Infiniband switches come with pre-integrated, highly available fabric management with seamless integration into Oracle Enterprise Manager Ops Center. In short: Oracle elevated the OFED InfiniBand stack into an enterprise-class networking infrastructure. Many years and multiple teams of manpower went into the above improvements - this is something you can only get from Oracle, because no other InfiniBand vendor can give you these features across the whole stack! Exabus: Because it's not About the Size of Your Network, it's How You Use it! So let's assume that you somehow were able to get your hands on an enterprise-class IB driver stack. Or maybe you don't care and are just happy with the standard OFED one? Anyway, the next step is to actually leverage that InfiniBand performance. Here are the choices: Use traditional TCP/IP on top of the InfiniBand stack, Develop your own integration between your middleware and the lower-level (but faster) InfiniBand protocols. While more bandwidth is always a good thing, it's actually the low latency that enables superior performance for your applications when running on any networking infrastructure: The lower the latency, the faster the response travels through the network and the more transactions you can close per second. The reason why InfiniBand is such a low latency technology is that it gets rid of most if not all of your traditional networking protocol stack: Data is literally beamed from one region of RAM in one server into another region of RAM in another server with no kernel/drivers/UDP/TCP or other networking stack overhead involved! Which makes option 1 a no-go: Adding TCP/IP on top of InfiniBand is like adding training wheels to your racing bike. It may be ok in the beginning and for development, but it's not quite the performance IB was meant to deliver. Which only leaves option 2: Integrating your middleware with fast, low-level InfiniBand protocols. And this is what Exalogic's "Exabus" technology is all about. Here are a few Exabus features that help applications leverage the performance of InfiniBand in Exalogic: RDMA and SDP integration at the JDBC driver level (SDP), for Oracle Weblogic (SDP), Oracle Coherence (RDMA), Oracle Tuxedo (RDMA) and the new Oracle Traffic Director (RDMA) on Exalogic. Using these protocols, middleware can communicate a lot faster with each other and the Oracle database than by using standard networking protocols, Seamless Integration of Ethernet over InfiniBand from Exalogic's Gateway switches into the OS, Oracle Weblogic optimizations for handling massive amounts of parallel transactions. Because if you have an 8-lane Autobahn, you also need to improve your ramps so you can feed it with many cars in parallel. Integration of Weblogic with Oracle Exadata for faster performance, optimized session management and failover. As you see, “Exabus” is Oracle's word for describing all the InfiniBand enhancements Oracle put into Exalogic: OFED stack enhancements, protocols for faster IB access, and InfiniBand support and optimizations at the virtualization and middleware level. All working together to deliver the full potential of InfiniBand performance. Who else has 100% control over their middleware so they can develop their own low-level protocol integration with InfiniBand? Even if you take an open source approach, you're looking at years of development work to create, test and support a whole new networking technology in your middleware! The Extras: Less Hassle, More Productivity, Faster Time to Market And then there are the other advantages of Engineered Systems that are true for Exalogic the same as they are for every other Engineered System: One simple purchasing process: No headaches due to endless RFPs and no “Will X work with Y?” uncertainties. Everything has been engineered together: All kinds of bugs and problems have been already fixed at the design level that would have only manifested themselves after you have built the system from scratch. Everything is built, tested and integrated at the factory level . Less integration pain for you, faster time to market. Every Exalogic machine world-wide is identical to Oracle's own machines in the lab: Instant replication of any problems you may encounter, faster time to resolution. Simplified patching, management and operations. One throat to choke: Imagine finger-pointing hell for systems that have been put together using several different vendors. Oracle's Engineered Systems have a single phone number that customers can call to get their problems solved. For more business-centric values, read The Business Value of Engineered Systems. Conclusion: Buy Exalogic, or get ready for a 6-12 Month Science Project And here's the reason why it's not easy to "build your own Exalogic": There's a lot of work required to make such a system fly. In fact, anybody who is starting to "just put together a bunch of servers and an InfiniBand network" is really looking at a 6-12 month science project. And the outcome is likely to not be very enterprise-class. And it won't have Exalogic's performance either. Because building an Engineered System is literally rocket science: It takes a lot of time, effort, resources and many iterations of design/test/analyze/fix to build such a system. That's why InfiniBand has been reserved for HPC scientists for such a long time. And only Oracle can bring the power of InfiniBand in an enterprise-class, ready-to use, pre-integrated version to customers, without the develop/integrate/support pain. For more details, check the new Exalogic overview white paper which was updated only recently. P.S.: Thanks to my colleagues Ola, Paul, Don and Andy for helping me put together this article! var flattr_uid = '26528'; var flattr_tle = 'How to Avoid Your Next 12-Month Science Project'; var flattr_dsc = 'While most customers immediately understand how the magic of Oracle's Hybrid Columnar Compression, intelligent storage servers and flash memory make Exadata uniquely powerful against home-grown database systems, some people think that Exalogic is nothing more than a bunch of x86 servers, a storage appliance and an InfiniBand (IB) network, built into a single rack.After all, isn't this exactly what the High Performance Computing (HPC) world has been doing for decades?On the surface, this may be true. And some people tried exactly that: They tried to put together their own version of Exalogic, but then they discover there's a lot more to building a system than buying hardware and assembling it together. IT is not Ikea.Why is that so? Could it be there's more going on behind the scenes than merely putting together a bunch of servers, a storage array and an InfiniBand network into a rack? Let's explore some of the special sauce that makes Exalogic unique and un-copyable, so you can save yourself from your next 6- to 12-month science project that distracts you from doing real work that adds value to your company.'; var flattr_tag = 'Engineered Systems,Engineered Systems,Infiniband,Integration,latency,Oracle,performance'; var flattr_cat = 'text'; var flattr_url = 'http://constantin.glez.de/blog/2012/04/how-avoid-your-next-12-month-science-project'; var flattr_lng = 'en_GB'

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  • HDMI Sound Stops Working

    - by stueng
    When not used for a few hours the sound stops working on my HTPC. To get sound to work again I have to unplug the HDMI cable and plug it back in again When this sound "outage" occurs, the HDMI device dissapears from the sound config output devices I see the following in dmesg [78534.010328] HDMI hot plug event: Codec=0 Pin=3 Presence_Detect=0 ELD_Valid=0 [78534.010363] HDMI status: Codec=0 Pin=3 Presence_Detect=0 ELD_Valid=0 [78558.948403] HDMI hot plug event: Codec=0 Pin=3 Presence_Detect=1 ELD_Valid=1 [78558.948429] HDMI status: Codec=0 Pin=3 Presence_Detect=0 ELD_Valid=0 [78562.579047] HDMI hot plug event: Codec=0 Pin=3 Presence_Detect=1 ELD_Valid=0 [78562.579078] HDMI status: Codec=0 Pin=3 Presence_Detect=1 ELD_Valid=1 [78562.579992] HDMI hot plug event: Codec=0 Pin=3 Presence_Detect=0 ELD_Valid=1 [78562.580043] HDMI status: Codec=0 Pin=3 Presence_Detect=1 ELD_Valid=1 [78562.876030] HDMI status: Codec=0 Pin=3 Presence_Detect=1 ELD_Valid=1 [78563.176036] HDMI status: Codec=0 Pin=3 Presence_Detect=1 ELD_Valid=1 [78563.195139] HDMI hot plug event: Codec=0 Pin=3 Presence_Detect=0 ELD_Valid=0 [78563.195169] HDMI status: Codec=0 Pin=3 Presence_Detect=0 ELD_Valid=0 [78563.476030] HDMI status: Codec=0 Pin=3 Presence_Detect=0 ELD_Valid=0 [78635.529493] HDMI hot plug event: Codec=0 Pin=3 Presence_Detect=1 ELD_Valid=1 [78635.529524] HDMI status: Codec=0 Pin=3 Presence_Detect=0 ELD_Valid=0 [78641.330701] HDMI hot plug event: Codec=0 Pin=3 Presence_Detect=1 ELD_Valid=0 [78641.330733] HDMI status: Codec=0 Pin=3 Presence_Detect=1 ELD_Valid=1 [78641.331649] HDMI hot plug event: Codec=0 Pin=3 Presence_Detect=0 ELD_Valid=1 [78641.331668] HDMI status: Codec=0 Pin=3 Presence_Detect=1 ELD_Valid=1 [78641.628050] HDMI status: Codec=0 Pin=3 Presence_Detect=1 ELD_Valid=1 [78641.928037] HDMI status: Codec=0 Pin=3 Presence_Detect=1 ELD_Valid=1 [78642.228042] HDMI status: Codec=0 Pin=3 Presence_Detect=1 ELD_Valid=1 [78642.528039] HDMI status: Codec=0 Pin=3 Presence_Detect=1 ELD_Valid=1 [78642.828037] HDMI status: Codec=0 Pin=3 Presence_Detect=1 ELD_Valid=1

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  • intermittent DNS problems

    - by jemminger
    How would I go about tracking this issue down? One of my websites has been up for years without issue. We're using Godaddy's nameservers for our domain. Lately in the past two weeks, I've noticed that once from home on my Cox cable connection, I could not connect to the site... it said the domain could not be resolved. I checked downforeveryoneorjustme.com, and it said it was fine. The "outage" lasted maybe five minutes (through a reboot too, and I'm on a mac FWIW) and then it started working again. Then it happened again this week, but from our office on a different Cox connection. Then it happened again from the office, but for a different domain. I called Cox during one outage, and the tech there could resolve the domain without a problem. When these outages are occurring, I can issue "host mydomain.com" and get "domain not found", but using "host mydomain.com 8.8.8.8" will resolve normally. Where do I start? We're getting reports now that our customers are experiencing it too.

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  • Internet suddenly stopped working

    - by user95629
    I was using NoMachine to access Ubuntu 11.10 when suddenly the internet on Ubuntu stopped working. Now Ubuntu doesn't recognize the internet at all (including locally). Symptoms: Doesn't recognize the fact that there is an ethernet cable attached. (I've tried switching cables, didn't work.) GUI says "No network devices available" Can't ping external IP addresses. Tried changing /etc/network/interfaces to eth1 instead of eth0 but it didn't work. ifconfig provides no output relating to eth0. When I type "/etc/init.d/networking restart" it tells me "Cannot find device 'eth0'/Failed to bring up eth0." The network settings had used a static IP address prior to the crash. I don't know why it won't recognize the ethernet (I think this is the fundamental problem, but I might be wrong) and why it stopped working so suddenly--I haven't installed any updates lately. Any ideas? Any more information I should provide? EDIT: lspci recognizes the Ethernet controller; netstat does not. lspci calls it "Intel Corporation Device 0000"

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  • Hardening network with sysctl settings made Wi-fi downloading speed extremely slow

    - by Rohit Bansal
    I just followed up following steps to harden network security The /etc/sysctl.conf file contain all the sysctl settings. Prevent source routing of incoming packets and log malformed IP's enter the following in a terminal window: sudo vi /etc/sysctl.conf Edit the `/etc/sysctl.conf` file and un-comment or add the following lines : # IP Spoofing protection net.ipv4.conf.all.rp_filter = 1 net.ipv4.conf.default.rp_filter = 1 # Ignore ICMP broadcast requests net.ipv4.icmp_echo_ignore_broadcasts = 1 # Disable source packet routing net.ipv4.conf.all.accept_source_route = 0 net.ipv6.conf.all.accept_source_route = 0 net.ipv4.conf.default.accept_source_route = 0 net.ipv6.conf.default.accept_source_route = 0 # Ignore send redirects net.ipv4.conf.all.send_redirects = 0 net.ipv4.conf.default.send_redirects = 0 # Block SYN attacks net.ipv4.tcp_syncookies = 1 net.ipv4.tcp_max_syn_backlog = 2048 net.ipv4.tcp_synack_retries = 2 net.ipv4.tcp_syn_retries = 5 # Log Martians net.ipv4.conf.all.log_martians = 1 net.ipv4.icmp_ignore_bogus_error_responses = 1 # Ignore ICMP redirects net.ipv4.conf.all.accept_redirects = 0 net.ipv6.conf.all.accept_redirects = 0 net.ipv4.conf.default.accept_redirects = 0 net.ipv6.conf.default.accept_redirects = 0 # Ignore Directed pings net.ipv4.icmp_echo_ignore_all = 1 To reload sysctl with the latest changes, enter: sudo sysctl -p But, after applying the changes I found "Wi-fi" downloading speed and terminal downloading speed extremely slow (less than 1KB/s) however surfing speed through browser was good. But, using direct ethernet cable was giving a good speed. Then, I reverted back the above changes and things fall back in line once again.... Could you please let me know what possibly in above script is affecting such behaviour [and why] ? How could I still maintain hardening of network security without disturbing Wi-fi downloading speed ?

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  • How to speed up file transfer to/from Ubuntu Server 11.10 (wifi)

    - by Alexander
    I've been searching AU & elsewhere for the last day and a half. Haven't found an answer so I joined AU to ask for help. I'm hoping someone can point me in the right direction. Ubuntu Server 11.10 Samba VSFTPD Windows 7 PC 2 MacBook Pro - Snow Leopard/Lion 1 iMac - Lion Wireless LAN using DLink DIR-655 Link Speed: 195 Mbit/s on Mac - 54Mbps on Windows ISP Connection: Cable - 20 down/3 up No Domain Controller. All machines are members of the same workgroup. No matter how I connect I can't get better than about 700K transfer rate up/down. Mac/PC, SMB/ftp, Domain Name/Local IP I've tried different user accounts and using different folders, different volumes on the server. Nothing seems to make a difference. 700K up/down. Period. Any suggestions would be greatly appreciated. Thanks, Alexander EDIT: Using sftp now and uploading seems to peak at 980k. After about 5 minutes into a 650MB file, downloading is at 1072k and climbing about 500b/s every ten seconds. If any of that matters... I was expecting a lot faster than 1Mb tx rate. Am I off base here? EDIT: From all I've read so far, perhaps the speed isn't that bad. I only installed Ubuntu out of boredom this past weekend. The trouble is, I like it. Guess it's time to ditch the wifi and run some Cat 5.

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