Re: [BackupPC-users] a one off backup of /boot partition in raid5 array - your thoughts/advice
On Thursday 16 March 2006 02:48, David Rees wrote: [...] My problem with 3ware controllers is that the 3dm monitoring software that works for a recent kernel does not support for older controllers (6xxx series in my case). I've got a couple 6xxx controllers and while Speaking of 3dm: my experiences with that are not so good. - no debian package I could find - bit of a weird startup procedure without clear messages if it started OK or not (and why it wouldn't start) - it had a memory leak - crashed every now and then That's with the version that came with my 7504 a few years back, so hopefully things have improved since then. Can't remember if I solved or worked around that. That particular machine is no longer running. I like the 3ware cards fine enough, but I think I would buy Areca stuff now, but they don't have a driver in the vanilla kernel source (it's in -mm though, but I don;t really want to run that on production servers). Just my 2 cents, Guus --- This SF.Net email is sponsored by xPML, a groundbreaking scripting language that extends applications into web and mobile media. Attend the live webcast and join the prime developer group breaking into this new coding territory! http://sel.as-us.falkag.net/sel?cmd=lnkkid=110944bid=241720dat=121642 ___ BackupPC-users mailing list BackupPC-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/backuppc-users http://backuppc.sourceforge.net/
Re: [BackupPC-users] a one off backup of /boot partition in raid5 array - your thoughts/advice
On 03/16 03:16 , Guus Houtzager wrote: Speaking of 3dm: my experiences with that are not so good. - no debian package I could find we ended up building our own. - bit of a weird startup procedure without clear messages if it started OK or not (and why it wouldn't start) - it had a memory leak - crashed every now and then 3dm2 is much more reliable than 3dm was. I like the 3ware cards fine enough, but I think I would buy Areca stuff now, but they don't have a driver in the vanilla kernel source (it's in -mm though, but I don;t really want to run that on production servers). I know someone who's used Areca cards; and he says they work fine under FreeBSD; but the linux drivers for them are too buggy. Drives will occasionally disappear from the array, and require a complete reboot to solve the issue. very high performance compared to 3ware, but the linux drivers need work. :( -- Carl Soderstrom Systems Administrator Real-Time Enterprises www.real-time.com --- This SF.Net email is sponsored by xPML, a groundbreaking scripting language that extends applications into web and mobile media. Attend the live webcast and join the prime developer group breaking into this new coding territory! http://sel.as-us.falkag.net/sel?cmd=lnkkid=110944bid=241720dat=121642 ___ BackupPC-users mailing list BackupPC-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/backuppc-users http://backuppc.sourceforge.net/
Re: [BackupPC-users] a one off backup of /boot partition in raid5 array - your thoughts/advice
On Wed, 15 Mar 2006, David Rees wrote: Partition all 3 disks the same way. Create a software RAID1 for the boot partition using those partitions. You'll have an extra partition so use it as a hot-spare. Or do a 3-way mirror. | nate carlson | [EMAIL PROTECTED] | http://www.natecarlson.com | | depriving some poor village of its idiot since 1981| --- This SF.Net email is sponsored by xPML, a groundbreaking scripting language that extends applications into web and mobile media. Attend the live webcast and join the prime developer group breaking into this new coding territory! http://sel.as-us.falkag.net/sel?cmd=lnkkid=110944bid=241720dat=121642 ___ BackupPC-users mailing list BackupPC-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/backuppc-users http://backuppc.sourceforge.net/
Re: [BackupPC-users] a one off backup of /boot partition in raid5 array - your thoughts/advice
On 3/16/06, Les Mikesell [EMAIL PROTECTED] wrote: I don't think I'd do raid5 in software but raid1 on scsi is very usable and better than nothing on IDE as long as the drives are on separate controllers. I've run software RAID5 in on Linux for quite some time without any problems while suffering through multiple drive failures. Software RAID5 is faster than hardware RAID5 in many cases because of the limited memory/CPU power on some cards. Make sure you do your homework before choosing a hardware RAID card if you want to do RAID5. Linux supports software RAID6 now which gets you 2 parity disks so you can suffer through 2 disk failures in a set before losing data which is nice. If using IDE I'd make sure that you're not sharing any cables for the same RAID set. -Dave --- This SF.Net email is sponsored by xPML, a groundbreaking scripting language that extends applications into web and mobile media. Attend the live webcast and join the prime developer group breaking into this new coding territory! http://sel.as-us.falkag.net/sel?cmd=lnkkid0944bid$1720dat1642 ___ BackupPC-users mailing list BackupPC-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/backuppc-users http://backuppc.sourceforge.net/
[BackupPC-users] a one off backup of /boot partition in raid5 array - your thoughts/advice
Hi all, I have setup a software raid5 array consisting of 3 sata hard drives with a small boot partition at the beginning of the first disk. Therefore the setup is as follows: _ sda | /boot | swap | raid5 | |___|___|___| sdb | raid5 | | |___|___| sdc | raid5 | | |___|___| The purpose of what I would like to do arrises from the fact that in the event of sda failure, I wont be able to boot the raid array. Therefore, perhaps I can make a one off backup of the /boot partition to backuppc and then should failure happen, I can just restore the backup of the /boot partition and have the machine boot, and raid5 will automatically recreate the failed raid partition on sda. I hope this makes sense; please correct me if I'm wrong. However, another option I am considering and am pushing for is to copy the boot partition over to sdb and sdc (in the area available after the raid partition). I know this can be done using the dd command but finding out where the free partitions on sdb and sdc start aswell as where the /boot partition ends is giving me problems. The partitions dont seem to add up! FYI: df -h FilesystemSize Used Avail Use% Mounted on /dev/md0 540G 1.4G 511G 1% / /dev/sda1 76M 13M 60M 18% /boot /dev/shm 501M 0 501M 0% /dev/shm hdparm /dev/sdXX /dev/sda1: IO_support = 0 (default 16-bit) readonly = 0 (off) readahead= 256 (on) geometry = 36483/255/63, sectors = 82220544, start = 63 /dev/sda2: IO_support = 0 (default 16-bit) readonly = 0 (off) readahead= 256 (on) geometry = 36483/255/63, sectors = 1061061120, start = 160650 /dev/sda3: IO_support = 0 (default 16-bit) readonly = 0 (off) readahead= 256 (on) geometry = 36483/255/63, sectors = 298939576320, start = 2233035 /dev/sdb1: IO_support = 0 (default 16-bit) readonly = 0 (off) readahead= 256 (on) geometry = 36481/255/63, sectors = 300066407424, start = 63 /dev/sdc1: IO_support = 0 (default 16-bit) readonly = 0 (off) readahead= 256 (on) geometry = 36481/255/63, sectors = 300066407424, start = 63 As far as I understand, with raid5, all raid5 partitions have to be the same size, so why aren't sda3, sdb1, sdc1 not the same size? I appreciate this is slightly off-topic but please advise me. Kindest Regards Khaled Hussain Server Administrator Coulomb Ltd --- This SF.Net email is sponsored by xPML, a groundbreaking scripting language that extends applications into web and mobile media. Attend the live webcast and join the prime developer group breaking into this new coding territory! http://sel.as-us.falkag.net/sel?cmd=lnkkid=110944bid=241720dat=121642 ___ BackupPC-users mailing list BackupPC-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/backuppc-users http://backuppc.sourceforge.net/
Re: [BackupPC-users] a one off backup of /boot partition in raid5 array - your thoughts/advice
On 03/15 11:28 , Khaled Hussain wrote: As far as I understand, with raid5, all raid5 partitions have to be the same size, so why aren't sda3, sdb1, sdc1 not the same size? With linux software RAID, the partitions don't have to be the same size (last I knew). You only get data protection up to the size of the smallest partition tho. (I don't remember whether it continues filling up space on the remaining drives, or whether it just runs out of space at that point tho. I would suspect the latter). I have a few pieces of advice for you: - Avoid software RAID if possible, especially in a commercial environment. The cost of a 3ware controller pretty much covers the time saved when a disk dies and you don't have to spend a couple hours monkeying with the array. (Software RAID arrays sometimes make the box fall over anyway when a disk dies. Your data may be saved, but the box still crashes.) - if you want a separate boot device for whatever reason, just put it on a wholly separate disk (or array of disks). I would suggest putting your important data on the array, and then the rest of the OS on the other drive. This way, if your boot/root disk dies, your important data is saved. If your array has problems, the boot/root disk provides the tools to fix it. - you can back up your boot/root drive with something like Mondo http://www.mondorescue.com/. Make that backup to CD, and when you need it, just put the CD in the drive, boot from it, and restore your system in whole or in part. -- Carl Soderstrom Systems Administrator Real-Time Enterprises www.real-time.com --- This SF.Net email is sponsored by xPML, a groundbreaking scripting language that extends applications into web and mobile media. Attend the live webcast and join the prime developer group breaking into this new coding territory! http://sel.as-us.falkag.net/sel?cmd=lnkkid=110944bid=241720dat=121642 ___ BackupPC-users mailing list BackupPC-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/backuppc-users http://backuppc.sourceforge.net/
Re: [BackupPC-users] a one off backup of /boot partition in raid5 array - your thoughts/advice
On 03/15 03:44 , Guus Houtzager wrote: It will use the largest common size of all 3 partitions. So if you've got for instance sda3 = 90 GB, sdb1 = 100 GB and sdc1 = 95 GB, your raid5 will be built from 3 x 90 GB. The leftover space of the partitions sdb1 and sdc1 will not be used. thanks for the clarification. :) A problem with hardware raid is that if your raidcontroller dies, you need exactly the same controller to get your array to work again. your point is valid. :) that said, I haven't had a real problem with 3ware controllers dying. (Promise Supertraks are another matter, but perhaps the bugs have been sorted out by now). -- Carl Soderstrom Systems Administrator Real-Time Enterprises www.real-time.com --- This SF.Net email is sponsored by xPML, a groundbreaking scripting language that extends applications into web and mobile media. Attend the live webcast and join the prime developer group breaking into this new coding territory! http://sel.as-us.falkag.net/sel?cmd=lnkkid=110944bid=241720dat=121642 ___ BackupPC-users mailing list BackupPC-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/backuppc-users http://backuppc.sourceforge.net/
Re: [BackupPC-users] a one off backup of /boot partition in raid5 array - your thoughts/advice
Carl Wilhelm Soderstrom wrote: A problem with hardware raid is that if your raidcontroller dies, you need exactly the same controller to get your array to work again. your point is valid. :) that said, I haven't had a real problem with 3ware controllers dying. (Promise Supertraks are another matter, but perhaps the bugs have been sorted out by now). We had problem with both Supertraks and 3ware controllers. The Supertrak problems may be related to using ide disks while the 3ware problems were (unfortunately not quite) DOA. Furthermore, I find the setup with raid controllers tedious: The modules often don't come with the distro and more often than not they do not load at boot forcing me to tweak /etc/rc.local. Anyway based on theses experiences I will only uses software raid unless we really need every CPU cycles. That said, I fortunately do not have a lot of experience with having to recover from software raid: up until now I only once had one software raid-5 go critical. Re Khaled Hussain issues: Linux can boot from raid-1. So you could chop off a partition from sdb for / and put swap on sdc. Another approach is to have alternative installation on a partition on sdb. This can be quite convenient for upgrades and error recovery. My 2 cc. ... Matt --- This SF.Net email is sponsored by xPML, a groundbreaking scripting language that extends applications into web and mobile media. Attend the live webcast and join the prime developer group breaking into this new coding territory! http://sel.as-us.falkag.net/sel?cmd=lnkkid=110944bid=241720dat=121642 ___ BackupPC-users mailing list BackupPC-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/backuppc-users http://backuppc.sourceforge.net/
Re: [BackupPC-users] a one off backup of /boot partition in raid5 array - your thoughts/advice
On 03/15 10:50 , Matt wrote: Furthermore, I find the setup with raid controllers tedious: The modules often don't come with the distro and more often than not they do not load at boot forcing me to tweak /etc/rc.local. haven't had that problem with 3ware controllers. linux kernels have had the drivers built in by default for years now. the 9000 series controllers require a 2.6.14 kernel or better, but that's the only issue I've had recently. -- Carl Soderstrom Systems Administrator Real-Time Enterprises www.real-time.com --- This SF.Net email is sponsored by xPML, a groundbreaking scripting language that extends applications into web and mobile media. Attend the live webcast and join the prime developer group breaking into this new coding territory! http://sel.as-us.falkag.net/sel?cmd=lnkkid=110944bid=241720dat=121642 ___ BackupPC-users mailing list BackupPC-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/backuppc-users http://backuppc.sourceforge.net/
Re: [BackupPC-users] a one off backup of /boot partition in raid5 array - your thoughts/advice
On Wed, 15 Mar 2006, Carl Wilhelm Soderstrom wrote: the 9000 series controllers require a 2.6.14 kernel or better, but that's the only issue I've had recently. Yeah, the 9550SX's need 2.6.14.. so if you're using an older distro that doesn't have 2.6.14 on it's installer, you're in for a world of hurt. :) (Debian's testing installer works fine, of course.) Also annoying when you want to swap a 9500S for a 9550SX, and don't upgrade your kernel beforehand.. that was a pain. | nate carlson | [EMAIL PROTECTED] | http://www.natecarlson.com | | depriving some poor village of its idiot since 1981| --- This SF.Net email is sponsored by xPML, a groundbreaking scripting language that extends applications into web and mobile media. Attend the live webcast and join the prime developer group breaking into this new coding territory! http://sel.as-us.falkag.net/sel?cmd=lnkkid=110944bid=241720dat=121642 ___ BackupPC-users mailing list BackupPC-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/backuppc-users http://backuppc.sourceforge.net/
Re: [BackupPC-users] a one off backup of /boot partition in raid5 array - your thoughts/advice
Best way I've found is to make /boot a small RAID1 (e.g. below is /dev/md0) on /dev/sda1 and /dev/sdb1, then your lilo conf just has to have these lines: boot=/dev/md0 raid-extra-boot=/dev/sda,/dev/sdb And if the sda disk dies, it will still boot of sdb and use the md0 to boot. Just thought I'd put a few more technical details rather than just saying this will work Linux can boot from raid-1. So you could chop off a partition from sdb for / and put swap on sdc. Another approach is to have alternative installation on a partition on sdb. This can be quite convenient for upgrades and error recovery. --- This SF.Net email is sponsored by xPML, a groundbreaking scripting language that extends applications into web and mobile media. Attend the live webcast and join the prime developer group breaking into this new coding territory! http://sel.as-us.falkag.net/sel?cmd=lnkkid=110944bid=241720dat=121642 ___ BackupPC-users mailing list BackupPC-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/backuppc-users http://backuppc.sourceforge.net/
Re: [BackupPC-users] a one off backup of /boot partition in raid5 array - your thoughts/advice
On Wed, 2006-03-15 at 16:36, Josh Marshall wrote: Best way I've found is to make /boot a small RAID1 (e.g. below is /dev/md0) on /dev/sda1 and /dev/sdb1, then your lilo conf just has to have these lines: boot=/dev/md0 raid-extra-boot=/dev/sda,/dev/sdb And if the sda disk dies, it will still boot of sdb and use the md0 to boot. Just thought I'd put a few more technical details rather than just saying this will work That is probably the best approach, but note that if you boot with grub you need to manually install it on the 2nd drive of the raid (or both, depending on the OS distribution and version). Also, many IDE disk failure modes will keep the machine from booting at all until the drive is removed. I'm not sure if that is a problem with SATA also or not. -- Les Mikesell [EMAIL PROTECTED] --- This SF.Net email is sponsored by xPML, a groundbreaking scripting language that extends applications into web and mobile media. Attend the live webcast and join the prime developer group breaking into this new coding territory! http://sel.as-us.falkag.net/sel?cmd=lnkkid=110944bid=241720dat=121642 ___ BackupPC-users mailing list BackupPC-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/backuppc-users http://backuppc.sourceforge.net/
Re: [BackupPC-users] a one off backup of /boot partition in raid5 array - your thoughts/advice
On 03/15 05:05 , Les Mikesell wrote: That is probably the best approach, but note that if you boot with grub you need to manually install it on the 2nd drive of the raid (or both, depending on the OS distribution and version). Also, many IDE disk failure modes will keep the machine from booting at all until the drive is removed. I'm not sure if that is a problem with SATA also or not. that's the main reason I avoid software RAID these days. I've seen disks fail in that way quite often; either crashing the box or just killing performance. (Bad drives sending constant bus resets, etc). -- Carl Soderstrom Systems Administrator Real-Time Enterprises www.real-time.com --- This SF.Net email is sponsored by xPML, a groundbreaking scripting language that extends applications into web and mobile media. Attend the live webcast and join the prime developer group breaking into this new coding territory! http://sel.as-us.falkag.net/sel?cmd=lnkkid=110944bid=241720dat=121642 ___ BackupPC-users mailing list BackupPC-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/backuppc-users http://backuppc.sourceforge.net/
Re: [BackupPC-users] a one off backup of /boot partition in raid5 array - your thoughts/advice
On 3/15/06, Carl Wilhelm Soderstrom [EMAIL PROTECTED] wrote: On 03/15 10:50 , Matt wrote: Furthermore, I find the setup with raid controllers tedious: The modules often don't come with the distro and more often than not they do not load at boot forcing me to tweak /etc/rc.local. haven't had that problem with 3ware controllers. linux kernels have had the drivers built in by default for years now. the 9000 series controllers require a 2.6.14 kernel or better, but that's the only issue I've had recently. My problem with 3ware controllers is that the 3dm monitoring software that works for a recent kernel does not support for older controllers (6xxx series in my case). I've got a couple 6xxx controllers and while they are still chugging along fine, the only way I get notified of drive failules is to watch /var/log/messages as I can't figure out how to get the RAID status through /proc or /sys. That's my only beef with the 3ware controllers that I've had, I haven't used any of the newer ones yet. -Dave --- This SF.Net email is sponsored by xPML, a groundbreaking scripting language that extends applications into web and mobile media. Attend the live webcast and join the prime developer group breaking into this new coding territory! http://sel.as-us.falkag.net/sel?cmd=lnkkid0944bid$1720dat1642 ___ BackupPC-users mailing list BackupPC-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/backuppc-users http://backuppc.sourceforge.net/
