Re: Linux NAS like Solution
Shalom Baruch. I have been using a server with 3ware SATA raid for a year and a half now, and a Silicon something or other (built in with dell servers), on a variety of IDE RAID 0,1 and 5 levels. As you said: IDE is unreliable; I have experienced a 2 out of 10 disk failures. You can't beat IDE for price, I needed TERABYTES, and SCSI would cost me about 4K$/TB while in IDE you can reach the TB scale on about 1K$/TB w/ software RAID 5 (w/o the controller). Nowadays, I wouldn't hesitate using software RAID (instead of the HW RAID I use). RAID initialization and maintenace can be performed decently with mdadm, even hotspares, etc, so it seems HW is not a must. The driver upgrade procedure for 3ware 7500 which I have is not simple, they require a simultaneous FIRMWARE, DRIVER and MONITORING/ CONFIGURATION SOFTWARE upgrade which was a bit cumbersome and costed quite a few hours to manage. Cheers, Miki Lewinger BGU = To unsubscribe, send mail to [EMAIL PROTECTED] with the word unsubscribe in the message body, e.g., run the command echo unsubscribe | mail [EMAIL PROTECTED]
Re: Linux NAS like Solution
On Sat, 12 Mar 2005 10:49:17 +0200, Tzafrir Cohen [EMAIL PROTECTED] wrote: Do you refer to a NAS that costs 2000$ as referred to in this thread or to a high-end NAS such as the one you use? Obviously I had our NAS system in my mind while I was writing, but I honestly belive that any dedicated NAS even the cheapest one (assuming it's a quality one) in terms of features and speed will be more stable and solid solution than a generic computer with DAS attached. -- Warm regards, Michael Green *^*^*^*^*^*^*^*^*^*^*^*^*^*^*^*^* Assistant Unix Admin Division of Information Systems Weizmann Institute of Science Rechovot 76100, Israel Tel.: 972-8-9344216 Fax.: 972-8-9344102 Cel.: 972-52-3638926 *^*^*^*^*^*^*^*^*^*^*^*^*^*^*^*^* = To unsubscribe, send mail to [EMAIL PROTECTED] with the word unsubscribe in the message body, e.g., run the command echo unsubscribe | mail [EMAIL PROTECTED]
Re: Linux NAS like Solution
I agree with Ariel. I'm administering NetApp NAS (relatevely high-end one I must admit) here. I've seen also SATA Raids baised on Intel server boards. You just cannot compare first to the second. In my opinion no Linux with whatever RAID will perform as good as a dedicated NAS machine that was designed and built from ground up to be NAS. Having a generic Linux computer with a RAID attached will just add an enormous amount to your administrative overhead. Go for NAS. = To unsubscribe, send mail to [EMAIL PROTECTED] with the word unsubscribe in the message body, e.g., run the command echo unsubscribe | mail [EMAIL PROTECTED]
Re: Linux NAS like Solution
Title: Linux NAS like Solution See inline. On Thu, 2005-03-10 at 11:07 +0200, Baruch Shpirer wrote: Hotswap can be done both in SATA and SCSI Both LSI and 3ware can do hotswap (and hotspare) SATA would be the cheap and risky solution where as SCSI is more expensive and reliable In my previous workplace we had both SCSI and SATA based storage (or actually streaming) solutions. SCSI is indeed by far more reliable; SATA drive usually had a much higher failure rate. (Including a couple of very troubling two drive death that killed the array.) Most SATA raid solutions are Soft Silicon - Software based and use the system main cpu for the raid operations , there are some HW based like 3ware. 3ware and LSI (megaraid) are both hardware solutions. *However* Tests I conducted seem to suggest that the Linux software RAID is actually faster then them both. This shouldn't surprise anyone; a fast P4/Athlon/Opteron CPU is about 30 times faster then the i8/9xx RISC controller used in the SCSI/SATA raid controllers. On a fast dual Xeon/Opteron server won't even notice the 1-2% CPU time spent on RAID5 reconstruction. ***Oh*** Make sure you do hotspare. By doing RAID5 without a hotspare you're essentially asking for it. (And it'll come...) Which seem on paper to be very good. The 3ware 7xxx and 8xxx are (very) reliable; though their write performance is less then impressive. (Read performance is OK.) The 3ware 9xxx has a much better benchmarking skills, but I'd stay clear of it for now; We had *way* too many reliability issues with this card. (3ware is working actively to fix the damaged firmware and improve the driver so YMMV.) Oh... 3ware's CLI tools are top notch; you'll be able to do most of the RAID's administration work using a simple bash script. The LSI card behaves much like it's SCSI cousin (it even uses the same driver.) One problem: LSI is miles behind 3ware when it comes to management tools. There's Adaptech and RaidCore; I've heard good things about them, but never had a chance to test them. Next is can I trust the SATA Raid controller to do real reliable Raid 5 ? Cause going for SCSI comes to a price that I rather pay for NAS 3ware 7xxx and 8xxx: Yes. 3ware 9xxx: Can't really tell right now. LSI: Yes. Did anyone see or hear about a SATA Raid controller do hotswap in linux ? Both 3ware and LSI. At times 3ware had problems detecting a replaced drive. (A bit of fancy CLI work always fixed the problem.) LSI works just fine. Iam using gentoo and gentoo forum pretty much covered the software issues, I just need to know my HW fits. BTW, you can do hotspare and hotswap in software RAID just as well. We had a SCSI software RAID solution (using a run-of-the-mill 29320 controller) and it worked just fine. (Besting the LSI MegaRAID solution by a nice margin.) Again, give it a go; while YMMV it may save you a couple of . Best regards Baruch Shpirer __ -- Gilboa Davara [EMAIL PROTECTED] Nice Systems
RE: Linux NAS like Solution
Title: Message On Thu, 2005-03-10 at 13:55 +0200, Baruch Shpirer wrote: First of all thank you for the fast and extensive answer but i have a few more: 1. Based on your experience from both scsi and sata what would be your recommidation for me ? Depends on the type of data you looking to store. Can you elaborate? 2. Same for software/hardware raid ? 3. Have you done something that smells like NAS from the outside ? if so, what about disk/raid monitoring ? Never had to. However, consider the fact the Linux is remotely manageable by design, most NAS just use the RAID and Linux tools without changing anything. -Original Message- From: Gilboa Davara [mailto:[EMAIL PROTECTED] Sent: Thursday, March 10, 2005 1:12 PM To: Baruch Shpirer Cc: linux-il@linux.org.il Subject: Re: Linux NAS like Solution See inline. On Thu, 2005-03-10 at 11:07 +0200, Baruch Shpirer wrote: Hotswap can be done both in SATA and SCSI Both LSI and 3ware can do hotswap (and hotspare) SATA would be the cheap and risky solution where as SCSI is more expensive and reliable In my previous workplace we had both SCSI and SATA based storage (or actually streaming) solutions. SCSI is indeed by far more reliable; SATA drive usually had a much higher failure rate. (Including a couple of very troubling two drive death that killed the array.) Most SATA raid solutions are Soft Silicon - Software based and use the system main cpu for the raid operations , there are some HW based like 3ware. 3ware and LSI (megaraid) are both hardware solutions. *However* Tests I conducted seem to suggest that the Linux software RAID is actually faster then them both. This shouldn't surprise anyone; a fast P4/Athlon/Opteron CPU is about 30 times faster then the i8/9xx RISC controller used in the SCSI/SATA raid controllers. On a fast dual Xeon/Opteron server won't even notice the 1-2% CPU time spent on RAID5 reconstruction. ***Oh*** Make sure you do hotspare. By doing RAID5 without a hotspare you're essentially asking for it. (And it'll come...) Which seem on paper to be very good. The 3ware 7xxx and 8xxx are (very) reliable; though their write performance is less then impressive. (Read performance is OK.) The 3ware 9xxx has a much better benchmarking skills, but I'd stay clear of it for now; We had *way* too many reliability issues with this card. (3ware is working actively to fix the damaged firmware and improve the driver so YMMV.) Oh... 3ware's CLI tools are top notch; you'll be able to do most of the RAID's administration work using a simple bash script. The LSI card behaves much like it's SCSI cousin (it even uses the same driver.) One problem: LSI is miles behind 3ware when it comes to management tools. There's Adaptech and RaidCore; I've heard good things about them, but never had a chance to test them. Next is can I trust the SATA Raid controller to do real reliable Raid 5 ? Cause going for SCSI comes to a price that I rather pay for NAS 3ware 7xxx and 8xxx: Yes. 3ware 9xxx: Can't really tell right now. LSI: Yes. Did anyone see or hear about a SATA Raid controller do hotswap in linux ? Both 3ware and LSI. At times 3ware had problems detecting a replaced drive. (A bit of fancy CLI work always fixed the problem.) LSI works just fine. Iam using gentoo and gentoo forum pretty much covered the software issues, I just need to know my HW fits. BTW, you can do hotspare and hotswap in software RAID just as well. We had a SCSI software RAID solution (using a run-of-the-mill 29320 controller) and it worked just fine. (Besting the LSI MegaRAID solution by a nice margin.) Again, give it a go; while YMMV it may save you a couple of . Best regards Baruch Shpirer __ -- Gilboa Davara [EMAIL PROTECTED] Nice Systems -- Gilboa Davara [EMAIL PROTECTED] Nice Systems
Re: Linux NAS like Solution
On Thursday 10 March 2005 11:07, Baruch Shpirer wrote: Hi, I have been fiddling for the last 2 weeks with idea of saving my company more then 2000$ and making my own kind of NAS like solution via linux. My considerations were highly to maintain the list of standard features NAS solution hold today including snapshots (lvm2) and hotswap disk rebuild. Hi Baruch, Unless this $2k is absolutely critical, I suggest you go for a supported and full featured NAS solution. What solutions exactly are $2k more expensive than what you propose ? None of the good ones are in that price range, and I am talking about prices for university, which are lower than usual, and still. --Ariel -- Ariel Biener e-mail: [EMAIL PROTECTED] PGP(6.5.8) public key http://www.tau.ac.il/~ariel/pgp.html = To unsubscribe, send mail to [EMAIL PROTECTED] with the word unsubscribe in the message body, e.g., run the command echo unsubscribe | mail [EMAIL PROTECTED]
Re: Linux NAS like Solution
Ariel Biener wrote: Unless this $2k is absolutely critical, I suggest you go for a supported and full featured NAS solution. What solutions exactly are $2k more expensive than what you propose ? None of the good ones are in that price range, and I am talking about prices for university, which are lower than usual, and still. Surprising as it is, I quite agree with Ariel. You will spend much more than US$2k implementing the solution, debugging it and (which, of course, is a good thing) you will be the sine qua non for your company. - they will never dare firing you. There are, if you wish to use a Linux-based solution, quite a few firms that do this. M = To unsubscribe, send mail to [EMAIL PROTECTED] with the word unsubscribe in the message body, e.g., run the command echo unsubscribe | mail [EMAIL PROTECTED]
RE: Linux NAS like Solution
Well... Even with the ppl I have read that had loss of data due to the use of such Systems, most of it comes from racklessness no backup. With hot swap and hot spare and I a nightly tape backup iam not that afraid from loss Of data. SATA raid has a lot of problems, a lot of BAD microcodes for HD controllers cause problems With the raid controllers. There is a none official list of those HDs in storage forums all Over. But still, I have read user comments for systems used in SMB With HW controllers such as LSI MegaRAID and 3Ware 8xxx which are working fine. The lowest good NAS solution I found was 4.5K$ , how can you compare that with a 1800$ solution with 350GB Neto ( After raid and snapshot deduction ) and I don't get University discounts Snapshots Hot spare Hot swap Power redundant And you can even spend another 250-600$ for external disk enclosure so it will be DAS like :) ( http://www.cwol.com/serial-ata/4-bay-hot-swap-raid-kit.htm ) You also have NAS os solutions like Darma OS if you dare to try http://nas.darma.com/products_home.html Or you can just compile your kernel and tune it for Network I/O and tweak the TCP to your usage -Original Message- From: Marc A. Volovic [mailto:[EMAIL PROTECTED] Sent: Thursday, March 10, 2005 9:18 PM To: Ariel Biener Cc: Baruch Shpirer; linux-il@linux.org.il Subject: Re: Linux NAS like Solution Ariel Biener wrote: Unless this $2k is absolutely critical, I suggest you go for a supported and full featured NAS solution. What solutions exactly are $2k more expensive than what you propose ? None of the good ones are in that price range, and I am talking about prices for university, which are lower than usual, and still. Surprising as it is, I quite agree with Ariel. You will spend much more than US$2k implementing the solution, debugging it and (which, of course, is a good thing) you will be the sine qua non for your company. - they will never dare firing you. There are, if you wish to use a Linux-based solution, quite a few firms that do this. M To unsubscribe, send mail to [EMAIL PROTECTED] with the word unsubscribe in the message body, e.g., run the command echo unsubscribe | mail [EMAIL PROTECTED]
