Re: Is Raid as frought as it looks?
Any chance of you providing a 'cookbook' on howto do this? Just an illustration of the commands to execute and what to do in what order? Note that for the fancy / clean way of doing this (rather than just ZAPPing the partition type, the SB or some such) needs patches to the patches ... Also, things get a *lot* more hairy if it's the root FS (and a to some extent harder if the FS is one which cannot be unmounted), so take care to note whether it's a data FS or a root FS ...
Re: Help with mirroring and Re: Raid 0 - mkraid aborted...
"Bruno Prior" [EMAIL PROTECTED] writes: The fact that the linux source includes legacy raid code which is incompatible with the latest raidtools seems to cause a lot of misunderstandings. Can't the legacy stuff be taken out and turned into a patch for those who like the older tools? I understood the current alpha code is scheduled for integration into the base kernel soon. However, if the error diagnostics of the raidtools were a bit better, we wouldn't have this question pop up all the time. "mkraid aborted" doesn't tell anyone anything. "protocol error, upgrade kernel raid support" would be much more informative. -- Osma Ahvenlampi
benchmarks
I've mostly been a lurker but recent changes in my company have peaked my interest in the performance of sw vs hw raid. Does anyone have some statistics online of sw raid (1,5) vs hw raid (1,5) on a linux system? Also is there anyway to have a hot-swappable sw raid system. (IDE or SCSI)? RTFM's and web page pointers are gladly accepted. thanks -sv
Re: benchmarks
Seth Vidal wrote: I've mostly been a lurker but recent changes in my company have peaked my interest in the performance of sw vs hw raid. Does anyone have some statistics online of sw raid (1,5) vs hw raid (1,5) on a linux system? We have a DPT midrange SmartRAID-V and we're going to do testing on two 7 x 17.5 GB RAID 5 arrays, one software, one hardware. We'll post the results as soon as they're available. (Testing will happen on a dual PII 350 w/ 256 MB RAM a cheezy IDE disk for /, running 2.2.6 (or later).) What kind of tests would people like to see run? The main test I'm going for is simply stability under load on bigish file systems biggish file operations. -- Josh Fishman NYU / RLab
Re: benchmarks
I've mostly been a lurker but recent changes in my company have peaked my interest in the performance of sw vs hw raid. Does anyone have some statistics online of sw raid (1,5) vs hw raid (1,5) on a linux system? We have a DPT midrange SmartRAID-V and we're going to do testing on two 7 x 17.5 GB RAID 5 arrays, one software, one hardware. We'll post the results as soon as they're available. (Testing will happen on a dual PII 350 w/ 256 MB RAM a cheezy IDE disk for /, running 2.2.6 (or later).) What kind of tests would people like to see run? The main test I'm going for is simply stability under load on bigish file systems biggish file operations. stability and read performance speeds and write performance speeds. possibly optimization for mostly-read situations, mostly-write situations and then both read and write situations. -sv
Re: RELEASE: RAID-0,1,4,5 patch 1999.04.21, 2.0.36/2.2.6
Hi! I'm a bit disappointed Martin Benes Patches are not included. We are running now 3 systems based on 19990309 + his patches + 2.0.36, and everything worked fine - from setting up to recovering RAID1. Another RAID5 system is working fine, but I did not really stress it till now. Though "Alpha" for the disk-IO-systems should mean something different than "Alpha" for a GUI-application and though I can't judge how many parts in the code remain "ugly", I'm pretty happy with the way things work by now. What makes me most unhappy is that I have to tell our guys to - take the kernel 2.0/2.x - add the alpha patches - add the Martin Bene patches on top on the alpha stuff just to get a kernel like we need it. To conclude, I suppose if the stuff is still considered to be alpha, it might be not such a high risk to merge Martins patches in. My personal experience was: RAID1/5 is reliable and working! Congratulation and thanks, Georg
Re: Is Raid as frought as it looks?
Any chance of you providing a 'cookbook' on howto do this? Just an illustration of the commands to execute and what to do in what order? Probably not until I migrate to the new raid tools. I did all this with the 0.42 tool set and am waiting for the current stuff to stabalize a little more. If you want to mess with it, steal one of your swap partitions and segment it into little 5 meg pieces and experiment. That's how I figured out how to do it the first time since the old tools don't really want you to mkraid a degraded set. I just put the same disk in the set twice and the tools were happy. As soon as the mkraid was complete I removed the duplicate entry and ran created the file system on the degraded md device. I don't know if this will work with the new tools. I've asked Mingo if this capability will be added to the tool set. Michael [EMAIL PROTECTED]
Re: System hang at shutdown
Hi Aaron, Have you tried upgrading glibc? There was a problem with older glibc's, where they would never close /etc/ld.so.cache, and hence the disk wouldn't be unmountable. Try upgrading to the latest glibc for RH5.2. (think it's in updates.) On Wed, 21 Apr 1999, Aaron D. Turner wrote: Not sure if this is a RAID issue, but I'm running out of things to blame it on. P2 450Mhz Genuine SymBios 53c895 2x Quantum Atlas III 9GB RAID 1 for all partitions except for swap 2.0.36 with raid0145-19990108-2.0.36 RAID tools 0.90 RH 5.2 Execute an init 0 or init 6 and it starts the shutdown process. The last lines it displays: Stopping kernel services: kerneld INIT: no more processes left in this runlevel And then it just hangs until I hit the reset button. It then boots, fsck's all the partitions and then RAID sync's the secondary to the master. Luckly this doesn't seem to cause any corruption. However since the machine is about a 45 minute drive away, its not very optimal to have to hit reset everytime I do an init 6 after a new kernel is compiled. Thoughts anyone? (raidtab/mdstat follow) Thanks! -- /etc/raidtab # Root paritition raiddev /dev/md0 raid-level 1 nr-raid-disks 2 nr-spare-disks 0 chunk-size 128 device /dev/sda2 raid-disk 0 device /dev/sdb2 raid-disk 1 # /var raiddev /dev/md1 raid-level 1 nr-raid-disks 2 nr-spare-disks 0 chunk-size 128 device /dev/sda3 raid-disk 0 device /dev/sdb3 raid-disk 1 # /tmp raiddev /dev/md2 raid-level 1 nr-raid-disks 2 nr-spare-disks 0 chunk-size 128 device /dev/sda5 raid-disk 0 device /dev/sdb5 raid-disk 1 # /usr raiddev /dev/md3 raid-level 1 nr-raid-disks 2 nr-spare-disks 0 chunk-size 128 device /dev/sda6 raid-disk 0 device /dev/sdb6 raid-disk 1 # /usr/local raiddev /dev/md4 raid-level 1 nr-raid-disks 2 nr-spare-disks 0 chunk-size 128 device /dev/sda7 raid-disk 0 device /dev/sdb7 raid-disk 1 # /home raiddev /dev/md5 raid-level 1 nr-raid-disks 2 nr-spare-disks 0 chunk-size 128 device /dev/sda8 raid-disk 0 device /dev/sdb8 raid-disk 1 -- /proc/mdstat Personalities : [raid1] read_ahead 1024 sectors md0 : active raid1 sdb2[1] sda2[0] 264960 blocks [2/2] [UU] md1 : active raid1 sdb3[1] sda3[0] 530048 blocks [2/2] [UU] md2 : active raid1 sdb5[1] sda5[0] 200704 blocks [2/2] [UU] md3 : active raid1 sdb6[1] sda6[0] 1052160 blocks [2/2] [UU] md4 : active raid1 sdb7[1] sda7[0] 5180800 blocks [2/2] [UU] md5 : active raid1 sdb8[1] sda8[0] 1052160 blocks [2/2] [UU] unused devices: none -- Paul Jakma [EMAIL PROTECTED] http://hibernia.clubi.ie PGP5 key: http://www.clubi.ie/jakma/publickey.txt --- Fortune: Anti-trust laws should be approached with exactly that attitude.
