Re: New approach with removable IDE RAID Backup (was: Tape Question)
Ramin Motakef [EMAIL PROTECTED] writes: Next thing i want to try is to use a dedicated maschine and raid over network block devices instead of rsync. Has anyone experience with that (speed, reliability)? I have no experience with it but have read a bit about it. The Problem with this setup is that you can't just unplug one machine since the raid partition will hang then. You have to reboot if one networked partition fails - at least that's what I read several times. What about using a native distributed filesystem like Inter-Mezzo, CODA or OpenAFS? I have read a bit about the first two and am planning to use one of then for a similar constellation. [x] ulf -- Save the whales - Feed the hungry - Free the mallocs
Re: New approach with removable IDE RAID Backup (was: Tape Question)
Hello Christian On 28 Aug 2002 at 0:39, Christian Hammers wrote: On Wed, Aug 21, 2002 at 04:14:09PM +1000, Craig Sanders wrote: I have a big size file about 33G in /home directory !!! and i wanna backup this file into tape device Why tape, buy a ATA (IDE) RAID controller that allowes hot swap and hot plugable devices (e.g. 3ware). Then setup a raid1 between two harddiscs. Whenever you like to do the backup simply mount that array, rsync /home to it and umount again. The next morning, exchange one of the discs agains a new one, the discs are your backup medium. The new disc will be rebuild automatically and be available for the next backup after a few hours. snip Any comments? We currently do this with 40 GB IDE drives, using Linux software raid1 and COLD swapping. (The server gets shut down twice a week). There are three drives. One permantly mounted, one in a removable drive bay in the server and one at home. Once a week I shut down the server and take the removeable drive out. I boot the server with one drive and take the removeable one home. Next day I bring the other drive back, shut the server down again and plug it in. Boot the server and start the raid started manually. We have live raid in the office and an offsite backup. Simple cheap and effective. (Note the three drives are never at the same place at the same time.) Regards Ian - Ian Forbes ZSD http://www.zsd.co.za Office: +27 21 683-1388 Fax: +27 21 674-1106 Snail Mail: P.O. Box 46827, Glosderry, 7702, South Africa -
Re: New approach with removable IDE RAID Backup (was: Tape Question)
Christian Hammers ch@westend.com writes: Hi On Wed, Aug 21, 2002 at 04:14:09PM +1000, Craig Sanders wrote: I have a big size file about 33G in /home directory !!! and i wanna backup this file into tape device Why tape, buy a ATA (IDE) RAID controller that allowes hot swap and hot plugable devices (e.g. 3ware). Then setup a raid1 between two harddiscs. Whenever you like to do the backup simply mount that array, rsync /home to it and umount again. The next morning, exchange one of the discs agains a new one, the discs are your backup medium. The new disc will be rebuild automatically and be available for the next backup after a few hours. Sounds strange? Well never got the change to test it myself but it could work. Benefits: - Cheaper: RAID Controller (300¤) + Drive Bay (200¤) + 4 drives (100¤ pro 60GB) are about 900¤. This is more than competable with DAT/DDS3 and even more with DLT tape drives. - Faster and easier when restoring. Obviously, just mount it. - More capacity per medium. Splitting up across several media makes things complicated. Any comments? bye, -christian- We use a (cold) removable IDE Drive for Backups of our Servers for some months now and are very happy with it. Setup is as follows: 2 removable 120GB IDE-Drives, one build in a normal Office PC (+ extra network cards), one at home. Drives are changed every week. The PC boots every day after office hours, rsyncs all the servers (70GB atm) and shuts itself down again. Each server has its own partition on the removeable drive which is bootable. So if one of the servers is going down, we just have to move the PC near it, plug it in and boot it. Max downtime 10 mins. Setup was fairly easy: Just a shell script to call rsync with a per server exclude-list of hardware-dependant config files, fstab etc. The main drawbacks are: - If a server goes down we loose one PC in the Office (not an issue, as there always some people on the road) - Syncronisation runs only once a day, so we will have to recover the changed files of the day by hand. - You have to think of the excluded config files when changing config on the servers. In addition we use tape backups for important stuff. Next thing i want to try is to use a dedicated maschine and raid over network block devices instead of rsync. Has anyone experience with that (speed, reliability)? Greetings, Ramin
New approach with removable IDE RAID Backup (was: Tape Question)
Hi On Wed, Aug 21, 2002 at 04:14:09PM +1000, Craig Sanders wrote: I have a big size file about 33G in /home directory !!! and i wanna backup this file into tape device Why tape, buy a ATA (IDE) RAID controller that allowes hot swap and hot plugable devices (e.g. 3ware). Then setup a raid1 between two harddiscs. Whenever you like to do the backup simply mount that array, rsync /home to it and umount again. The next morning, exchange one of the discs agains a new one, the discs are your backup medium. The new disc will be rebuild automatically and be available for the next backup after a few hours. Sounds strange? Well never got the change to test it myself but it could work. Benefits: - Cheaper: RAID Controller (300¤) + Drive Bay (200¤) + 4 drives (100¤ pro 60GB) are about 900¤. This is more than competable with DAT/DDS3 and even more with DLT tape drives. - Faster and easier when restoring. Obviously, just mount it. - More capacity per medium. Splitting up across several media makes things complicated. Any comments? bye, -christian- -- Christian HammersWESTEND GmbH - Aachen und Dueren Tel 0241/701333-0 ch@westend.com Internet Security for ProfessionalsFax 0241/911879 WESTEND ist CISCO Systems Partner - Authorized Reseller
Re: New approach with removable IDE RAID Backup (was: Tape Question)
On Wed, Aug 28, 2002 at 12:39:26AM +0200, Christian Hammers wrote: On Wed, Aug 21, 2002 at 04:14:09PM +1000, Craig Sanders wrote: I have a big size file about 33G in /home directory !!! and i wanna backup this file into tape device Why tape, buy a ATA (IDE) RAID controller that allowes hot swap and hot plugable devices (e.g. 3ware). Then setup a raid1 between two harddiscs. [...] not a bad idea. i've seen similar ideas before, but since they didn't involve hot-swap drives i considered them to be hopelessly impractical. it's a lot more feasible with hot-swap drives. Any comments? 1. as well as the raid rebuild, you still need to rsync the new/changed data to the raid array after a drive has been hot-swapped - and ideally, that should be delayed until after the rebuild has completeddoes the 3ware unit have tools for monitoring the progress/status of the rebuild? 2. what about off-site backup? or archiving? i think a tape drive is still needed for these purposes. drives are too fragile to carry back and forth between home and work every day, and still too expensive to just sit one on the shelf for an archive (and how would you restore archived data if the raid unit will rebuild it to the latest version as soon as you plug it in?) craig -- craig sanders [EMAIL PROTECTED] Fabricati Diem, PVNC. -- motto of the Ankh-Morpork City Watch
Re: New approach with removable IDE RAID Backup (was: Tape Question)
Hi Why tape, buy a ATA (IDE) RAID controller that allowes hot swap and hot plugable devices (e.g. 3ware). Then setup a raid1 between two harddiscs. [...] On Wed, Aug 28, 2002 at 09:56:52AM +1000, Craig Sanders wrote: 1. as well as the raid rebuild, you still need to rsync the new/changed data to the raid array after a drive has been hot-swapped - and ideally, that should be delayed until after the rebuild has completeddoes the 3ware unit have tools for monitoring the progress/status of the rebuild? Yes, even logs to syslog through a 3ware daemon. 2. what about off-site backup? or archiving? i think a tape drive is still needed for these purposes. drives are too fragile to carry back and forth between home and work every day, and still too expensive to just sit one on the shelf for an archive Well, it sounds like waste but considering the price for a DLT drive (DDS3 is often too slow or too small) then its even cheaper to buy IDE drives. Carrying around IDE drives might be dangerous but I think they should be take no harm if one is careful. archived data if the raid unit will rebuild it to the latest version as soon as you plug it in?) My idea was, that the 3ware controller has at least 4 ports and my drive bay handles 3 drives in a high of 2 5.25 bays. So I could configure the raid to have 2 drives RAID1 and one drive just as-is. Plugging the drive into this bay would give me a /dev/sdb or so which I could use for restoring. Or, in this case one could use the BIOS utility or the 3ware daemon with web frontent (usable with lynx) to reconfigure the raid before inserting the restore drive as only drive in JBOD mode. As restores are not so common this could be ok. At least you can even have the possibility to boot from this drive (restoring from a tape is hard if you cannot boot anymore...) bye, -christian- -- Christian HammersWESTEND GmbH - Aachen und Dueren Tel 0241/701333-0 ch@westend.com Internet Security for ProfessionalsFax 0241/911879 WESTEND ist CISCO Systems Partner - Authorized Reseller
