Re: [CentOS] 4 X 500 gb drives - best software raid config for a backup server?

> > If I have to do hardware raid, I'll definitely spec in a backup > controller. Learnt this the hard way when my raid 5 controller died > years after I first got it and I could no longer find a replacement. > > For high budget projects, having the extra raid controller as > insurance isn't a

Re: [CentOS] 4 X 500 gb drives - best software raid config for a backup server?

On Sun, Feb 22, 2009 at 7:05 PM, Ian Forde wrote: > RAID in software, whether RAID1 or RAID5/6, always has manual steps > involved in recovery. If one is using standardized hardware, such as HP > DL-x80 hardware or Dell x950 boxes, HW RAID obviates the need for a > "recovery procedure". It's ju

Re: [CentOS] 4 X 500 gb drives - best software raid config for a backup server?

Ian Forde wrote: > On Sat, 2009-02-21 at 18:09 -0600, Les Mikesell wrote: >> Yes, but raid1 in software has none of those problems, since as far as >> the boot loader is concerned, you are booting from a single drive. And >> there is a trade-off in complexity, since sw raid works the same on >>

Re: [CentOS] 4 X 500 gb drives - best software raid config for a backup server?

Kay Diederichs wrote: > A good place to start comparing benchmark numbers for different RAID > levels is > http://linux-raid.osdl.org/index.php/Performance > in particular the links given in section "Other benchmarks from 2007-2008" > I like this bit of info from http://linux-raid.osdl.org/ind

Re: [CentOS] 4 X 500 gb drives - best software raid config for a backup server?

>> You will have to prove that. I have previously posted posts with links >> to benchmarks that show that hardware raid with sufficient processing >> power beat the pants of software raid when it comes to raid5/6 >> implementations. Hardware raid cards no longer come with crappy i960 cpus. >

Re: [CentOS] 4 X 500 gb drives - best software raid config for a backup server?

On Sat, 2009-02-21 at 18:09 -0600, Les Mikesell wrote: > Yes, but raid1 in software has none of those problems, since as far as > the boot loader is concerned, you are booting from a single drive. And > there is a trade-off in complexity, since sw raid works the same on > Linux across different

Re: [CentOS] 4 X 500 gb drives - best software raid config for a backup server?

Ian Forde wrote: > On Sat, 2009-02-21 at 17:24 -0600, Les Mikesell wrote: >> Ian Forde wrote: >>> Might not be a bad idea to see how they're able to use >>> mdadm to detect and autosync drives. I don't *ever* want to go through >>> something like: >>> >>> http://kev.coolcavemen.com/2008/07/heroic-

Re: [CentOS] 4 X 500 gb drives - best software raid config for a backup server?

On Sat, 2009-02-21 at 17:24 -0600, Les Mikesell wrote: > Ian Forde wrote: > > Might not be a bad idea to see how they're able to use > > mdadm to detect and autosync drives. I don't *ever* want to go through > > something like: > > > > http://kev.coolcavemen.com/2008/07/heroic-journey-to-raid-5-d

Re: [CentOS] 4 X 500 gb drives - best software raid config for a backup server?

Ian Forde wrote: > Might not be a bad idea to see how they're able to use > mdadm to detect and autosync drives. I don't *ever* want to go through > something like: > > http://kev.coolcavemen.com/2008/07/heroic-journey-to-raid-5-data-recovery/ > > Not when a little planning can help me skip it..

Re: [CentOS] 4 X 500 gb drives - best software raid config for a backup server?

A good place to start comparing benchmark numbers for different RAID levels is http://linux-raid.osdl.org/index.php/Performance in particular the links given in section "Other benchmarks from 2007-2008" HTH, Kay ___ CentOS mailing list CentOS@centos.o

Re: [CentOS] 4 X 500 gb drives - best software raid config for a backup server?

On Sat, 2009-02-21 at 08:40 +0800, Chan Chung Hang Christopher wrote: > Ian Forde wrote: > > I'd have to say no on the processing power for RAID 5. Moore's law has > > grown CPU capabilities over the last 15 or so years. HW RAID > > controllers haven't gotten that much faster because they haven't

Re: [CentOS] 4 X 500 gb drives - best software raid config for a backup server?

Chan Chung Hang Christopher wrote: > >> We were talking about RAID1; RAID5/6 is a different area. Linux software >> RAID1 is a safeguard against disk failure; it's not designed for speed >> increase. There is a number of things that could be improved in Linux >> software RAID; read performan

Re: [CentOS] 4 X 500 gb drives - best software raid config for a backup server?

On Sat, Feb 21, 2009 at 11:42 PM, Chan Chung Hang Christopher < christopher.c...@bradbury.edu.hk> wrote: > > Would running two CP command to copy 2 different set of files to two >> different targets suffice as a basic two thread test? >> >> > So long as you generate disk access through a file sys

Re: [CentOS] 4 X 500 gb drives - best software raid config for a backup server?

Kay Diederichs wrote: > Chan Chung Hang Christopher schrieb: > >>> "md1 will read from both disk" is not true in general. >>> RAID1 md reads from one disk only; it uses the other one in case the >>> first one fails. No performance gain from multiple copies. >>> >>> >> I beg to differ.

Re: [CentOS] 4 X 500 gb drives - best software raid config for a backup server?

Would running two CP command to copy 2 different set of files to two different targets suffice as a basic two thread test? So long as you generate disk access through a file system and not hdparm. Is there a way to monitor actual disk transfers from command line without having to do manual

Re: [CentOS] 4 X 500 gb drives - best software raid config for a backup server?

On Sat, Feb 21, 2009 at 6:04 PM, John R Pierce wrote: > Kay Diederichs wrote: > > hdparm -tT tests one type of disk access, other tools test other > > aspects. I gave the hdparm numbers because everyone can reproduce them. > > For RAID0 with two disks you do see - using e.g. hdparm - the doubling

Re: [CentOS] 4 X 500 gb drives - best software raid config for a backup server?

Kay Diederichs wrote: > hdparm -tT tests one type of disk access, other tools test other > aspects. I gave the hdparm numbers because everyone can reproduce them. > For RAID0 with two disks you do see - using e.g. hdparm - the doubling > of performance from two disks. > If you take the time to r

Re: [CentOS] 4 X 500 gb drives - best software raid config for a backup server?

Chan Chung Hang Christopher schrieb: >> "md1 will read from both disk" is not true in general. >> RAID1 md reads from one disk only; it uses the other one in case the >> first one fails. No performance gain from multiple copies. >> > I beg to differ. I have disks in a raid1 md array and iostat

Re: [CentOS] 4 X 500 gb drives - best software raid config for a backup server?

Ian Forde wrote: > On Fri, 2009-02-20 at 22:52 +0800, Chan Chung Hang Christopher wrote: > >> Bollocks. The only area in which hardware raid has a significant >> performance advantage over software raid is raid5/6 given sufficient >> cache memory and processing power. >> > > I'd have to s

Re: [CentOS] 4 X 500 gb drives - best software raid config for a backup server?

On Fri, 2009-02-20 at 22:52 +0800, Chan Chung Hang Christopher wrote: > Bollocks. The only area in which hardware raid has a significant > performance advantage over software raid is raid5/6 given sufficient > cache memory and processing power. I'd have to say no on the processing power for RAID

Re: [CentOS] 4 X 500 gb drives - best software raid config for a backup server?

> "md1 will read from both disk" is not true in general. > RAID1 md reads from one disk only; it uses the other one in case the > first one fails. No performance gain from multiple copies. > I beg to differ. I have disks in a raid1 md array and iostat -x 1 will show reads coming off both disk

Re: [CentOS] 4 X 500 gb drives - best software raid config for a backup server?

Noob Centos Admin schrieb: > > > On Thu, Feb 19, 2009 at 4:22 AM, Ray Van Dolson > wrote: > > The other side of the coin (as I think you mentioned) is that many are > not comfortable having LVM handle the mirroring. Are its mirroring > abilities as mature

Re: [CentOS] 4 X 500 gb drives - best software raid config for a backup server?

On Thu, Feb 19, 2009 at 4:22 AM, Ray Van Dolson wrote: > The other side of the coin (as I think you mentioned) is that many are > not comfortable having LVM handle the mirroring. Are its mirroring > abilities as mature or fast as md? It's certainly not documented as > well at the very least. :)

Re: [CentOS] 4 X 500 gb drives - best software raid config for a backup server?

On Wed, Feb 18, 2009 at 06:20:59PM -0500, Ross Walker wrote: > On Feb 18, 2009, at 2:29 PM, Ray Van Dolson wrote: > > > On Wed, Feb 18, 2009 at 11:12:13AM -0800, John R Pierce wrote: > >> Scott Silva wrote: > >>> You can make LVM over raid 1's in Disk Druid, but I don't think it > >>> will do >

Re: [CentOS] 4 X 500 gb drives - best software raid config for a backup server?

On Feb 18, 2009, at 2:29 PM, Ray Van Dolson wrote: > On Wed, Feb 18, 2009 at 11:12:13AM -0800, John R Pierce wrote: >> Scott Silva wrote: >>> You can make LVM over raid 1's in Disk Druid, but I don't think it >>> will do >>> raid 10. And you cannot boot from software raid 5 (yet). >>> >> >> a L

Re: [CentOS] 4 X 500 gb drives - best software raid config for a backup server?

> a LVM over several raid 1's is effectively raid10 as LVM will stripe the > volumes across the devices. It would be nice if LVM could do > mirorring too (like LVM on AIX does) and was tighter integrated with the > file system tools (again, like LVM on AIX... grow a LV and it grows the > J

Re: [CentOS] 4 X 500 gb drives - best software raid config for a backup server?

John R Pierce wrote: > Ray Van Dolson wrote: >> Can't Linux LVM do mirroring? I swear I read that it could in the man >> page. Never have tried it however and you certainly can't set it up >> from disk druid in anaconda. >> > > > dunno. the word 'mirror occurs exactly once in the man page f

Re: [CentOS] 4 X 500 gb drives - best software raid config for a backup server?

On Wed, Feb 18, 2009 at 11:51:55AM -0800, John R Pierce wrote: > Ray Van Dolson wrote: > > Can't Linux LVM do mirroring? I swear I read that it could in the man > > page. Never have tried it however and you certainly can't set it up > > from disk druid in anaconda. > > > > > dunno. the word

Re: [CentOS] 4 X 500 gb drives - best software raid config for a backup server?

Ray Van Dolson wrote: > Can't Linux LVM do mirroring? I swear I read that it could in the man > page. Never have tried it however and you certainly can't set it up > from disk druid in anaconda. > dunno. the word 'mirror occurs exactly once in the man page for lvm(8) lvconvert -- C

Re: [CentOS] 4 X 500 gb drives - best software raid config for a backup server?

On Wed, 2009-02-18 at 08:13 -0800, dnk wrote: > On 18-Feb-09, at 2:01 AM, John Doe wrote: > > >>> For controller, what is the interface on your drives?? SCSI, SAS?? > >> Dell 2950, SAS 6 Host Bus Controller. > > > > Integrated SAS 6/i(base): 4 port SAS controller (does support RAID > > 0/1) > >

Re: [CentOS] 4 X 500 gb drives - best software raid config for a backup server?

On Wed, Feb 18, 2009 at 11:12:13AM -0800, John R Pierce wrote: > Scott Silva wrote: > > You can make LVM over raid 1's in Disk Druid, but I don't think it will do > > raid 10. And you cannot boot from software raid 5 (yet). > > > > a LVM over several raid 1's is effectively raid10 as LVM will s

Re: [CentOS] 4 X 500 gb drives - best software raid config for a backup server?

on 2-18-2009 11:12 AM John R Pierce spake the following: > Scott Silva wrote: >> You can make LVM over raid 1's in Disk Druid, but I don't think it will do >> raid 10. And you cannot boot from software raid 5 (yet). >> > > a LVM over several raid 1's is effectively raid10 as LVM will stripe the

Re: [CentOS] 4 X 500 gb drives - best software raid config for a backup server?

Scott Silva wrote: > You can make LVM over raid 1's in Disk Druid, but I don't think it will do > raid 10. And you cannot boot from software raid 5 (yet). > a LVM over several raid 1's is effectively raid10 as LVM will stripe the volumes across the devices. It would be nice if LVM could do

Re: [CentOS] 4 X 500 gb drives - best software raid config for a backup server?

on 2-18-2009 10:13 AM dnk spake the following: > > On 18-Feb-09, at 9:14 AM, Scott Silva wrote: > >> http://tldp.org/HOWTO/Software-RAID-HOWTO.html >> >> http://www.linuxdevcenter.com/pub/a/linux/2002/12/05/RAID.html > > If i am to understand the tutorials right, does one create the raid/lvm > a

Re: [CentOS] 4 X 500 gb drives - best software raid config for a backup server?

On 18-Feb-09, at 9:14 AM, Scott Silva wrote: http://tldp.org/HOWTO/Software-RAID-HOWTO.html http://www.linuxdevcenter.com/pub/a/linux/2002/12/05/RAID.html If i am to understand the tutorials right, does one create the raid/ lvm after install? Or do you boot off the disk, use these tools, th

Re: [CentOS] 4 X 500 gb drives - best software raid config for a backup server?

on 2-17-2009 1:52 PM dnk spake the following: > Hi there, > > I am currently setting up a server that will house my backups (simply > using rsync). > > This system has 4 X 500 gb drives and I am looking to raid for max > drive space and data safety. Performance is not so much a concern. Max

Re: [CentOS] 4 X 500 gb drives - best software raid config for a backup server?

On 18-Feb-09, at 8:17 AM, Ray Van Dolson wrote: > So this isn't the PERC then? The PERC should be real hardware RAID... > > Ray It is the SAS 6/i. d ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/listinfo/centos

Re: [CentOS] 4 X 500 gb drives - best software raid config for a backup server?

On Wed, Feb 18, 2009 at 08:13:23AM -0800, dnk wrote: > > On 18-Feb-09, at 2:01 AM, John Doe wrote: > > >>> For controller, what is the interface on your drives?? SCSI, SAS?? > >> Dell 2950, SAS 6 Host Bus Controller. > > > > Integrated SAS 6/i(base): 4 port SAS controller (does support RAID >

Re: [CentOS] 4 X 500 gb drives - best software raid config for a backup server?

On 18-Feb-09, at 2:01 AM, John Doe wrote: >>> For controller, what is the interface on your drives?? SCSI, SAS?? >> Dell 2950, SAS 6 Host Bus Controller. > > Integrated SAS 6/i(base): 4 port SAS controller (does support RAID > 0/1) > But I don't know if that is descent hw raid or crap raid...

Re: [CentOS] 4 X 500 gb drives - best software raid config for a backup server?

> > For controller, what is the interface on your drives?? SCSI, SAS?? > Dell 2950, SAS 6 Host Bus Controller. Integrated SAS 6/i(base): 4 port SAS controller (does support RAID 0/1) But I don't know if that is descent hw raid or crap raid... JD ___

Re: [CentOS] 4 X 500 gb drives - best software raid config for a backup server?

> Would it be best to raid 1 two drives each and LVM them together? > > My next question would be about how to do this as I have never done a > linux software raid. > I would do it this way if they are not system disks: Eg: sdc + sdd = md0 (raid 1) sde + sdf = md1 (raid 1) md0 + md1 = md2 (

Re: [CentOS] 4 X 500 gb drives - best software raid config for a backup server?

Dnk, I use two drives with linux raid 1 sets for the OS for all my CentOS machines, drives are cheaper than my rebuild time and hassle. I actually use 3 partitions mirrored on each: /boot of 100M; swap of 2 time RAM (disk is cheap); 70G as /, then the remainder is extended partition for lvm -

Re: [CentOS] 4 X 500 gb drives - best software raid config for a backup server?

On 17-Feb-09, at 2:08 PM, Rob Kampen wrote: Linux software raid works fine and I use this recipe http://linux-raid.osdl.org/index.php/Partitioning_RAID_/_LVM_on_RAID If you can afford a proper hardware raid controller for raid 6, that would be of better performance than linux software raid, o

Re: [CentOS] 4 X 500 gb drives - best software raid config for a backup server?

On 17-Feb-09, at 2:01 PM, John Plemons wrote: > For controller, what is the interface on your drives?? SCSI, SAS?? > > John Plemons > Dell 2950, SAS 6 Host Bus Controller. d ___ CentOS mailing list CentOS@centos.org http://lists.centos.org/mailman/

Re: [CentOS] 4 X 500 gb drives - best software raid config for a backup server?

dnk wrote: Hi there, I am currently setting up a server that will house my backups (simply using rsync). This system has 4 X 500 gb drives and I am looking to raid for max drive space and data safety. Performance is not so much a concern. My experience with software raids in nil, so so

Re: [CentOS] 4 X 500 gb drives - best software raid config for a backup server?

On Tue, Feb 17, 2009 at 01:52:52PM -0800, dnk wrote: > Hi there, > > I am currently setting up a server that will house my backups (simply > using rsync). > > This system has 4 X 500 gb drives and I am looking to raid for max > drive space and data safety. Performance is not so much a concern

Re: [CentOS] 4 X 500 gb drives - best software raid config for a backup server?

For controller, what is the interface on your drives?? SCSI, SAS?? John Plemons dnk wrote: > Hi there, > > I am currently setting up a server that will house my backups (simply > using rsync). > > This system has 4 X 500 gb drives and I am looking to raid for max > drive space and data saf

[CentOS] 4 X 500 gb drives - best software raid config for a backup server?

Hi there, I am currently setting up a server that will house my backups (simply using rsync). This system has 4 X 500 gb drives and I am looking to raid for max drive space and data safety. Performance is not so much a concern. My experience with software raids in nil, so some of these may s