Re: raidtools to mdadm
Casey Boone wrote: ok so i am trying to recover some data for a friend. what i am wanting to do is forcibly set up /dev/mdN to be a raid0 of /dev/sda and /dev/sdb i do not want to actually change any of the contents of these drives, just mount very simply as a raid0. the raid was originally created using an onboard nvidia raid on the motherboard these drives used to be hooked to. my friend thought he could shove them into another windows box (that is what he was running on them) and have windows recover the raid. all this did was totally destroy the superblock on one of the two drives. dmraid now wont see them as a matched pair so that is out. the actual data areas of both drives seems to be intact, but unless i can get them into raid0 i dont know how i can recover the data. it figures he gives me the drives after he makes it a notch or two more of a pain :\ I have friends like that too. ;-) now before the advent of mdadm i would use /etc/raidtab and have no issues setting up the raid device. \ I haven't used raidtools for ages, but can't you bring yourself to using them now? I seem to remember that there was no superblock to be written in a bad place, which might be an advantage. mdadm has several versions which write the superblock in various places on the drives, and you may want none of the above. Alternatively, if these are fairly small, write a tiny program to open both physical devices, read a chunk from one, then the other, repeat while writing to something not hosed. as best i can tell i am using the correct commands for what i want but i pretty much get nothing but errors: [EMAIL PROTECTED]:/media# mdadm --build /dev/md1 --chunk=128 --level=0 --raid-devices=2 /dev/sda /dev/sdb mdadm: error opening /dev/md1: No such device or address [EMAIL PROTECTED]:/media# mdadm --build -n 2 -c 128 -l 0 /dev/md1 /dev/sda /dev/sdb mdadm: error opening /dev/md1: No such device or address when i run those commands i do get /dev/mdN entries created, but they do not point to a valid block device (as tested with fdisk -l and with dmraid -b) for the life of me i dont understand why anyone would put important data on a raid0, but that is what happened in this case. If i have to i will drop down to an older knoppix release to get raidtools back, as i have never had any issues in recovering crap onboard raid arrays nor windows software raid arrays under it. i am sure it can be done with mdadm but for the life of me i cannot seem to figure out exactly how. any help on this would be greatly appreciated Casey -- bill davidsen [EMAIL PROTECTED] CTO TMR Associates, Inc Doing interesting things with small computers since 1979 - To unsubscribe from this list: send the line unsubscribe linux-raid in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: raidtools to mdadm
i do not want to actually change any of the contents of these drives, just mount very simply as a raid0. the raid was originally created using an onboard nvidia raid on the motherboard these drives used to be hooked to. my friend thought he could shove them into another windows box (that is what he was running on them) and have windows recover the raid. all this did was totally destroy the superblock on one of the two drives. dmraid now wont see them as a matched pair so that is out. the actual data areas of both drives seems to be intact, but unless i can get them into raid0 i dont know how i can recover the data. it figures he gives me the drives after he makes it a notch or two more of a pain :\ I have friends like that too. ;-) gotta love 'em wish i was getting paid for this one now before the advent of mdadm i would use /etc/raidtab and have no issues setting up the raid device. \ I haven't used raidtools for ages, but can't you bring yourself to using them now? I seem to remember that there was no superblock to be written in a bad place, which might be an advantage. mdadm has several versions which write the superblock in various places on the drives, and you may want none of the above. Alternatively, if these are fairly small, write a tiny program to open both physical devices, read a chunk from one, then the other, repeat while writing to something not hosed. at the suggestion of another on the list (thanks neil brown!) i tried modprobing a slew of things related to the disk mapper to no avail, then i gave up using knoppix and tried with a fedora 6 box (after i dd-ed the drives off to a larger drive) and it worked great. i can definitely say that while mdadm is quite foreign territory for me, i love the fact i can specify everything i want to happen on one command line. btw once i actually did get the drives raided it turns out that while the partition table was intact, somehow the partition itself was fubarred enough that i couldnt mount it to save my life. finally just told the guy you screwed it by trying to recover it, next time bring me the drives the MOMENT you have a problem Casey - To unsubscribe from this list: send the line unsubscribe linux-raid in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
raidtools to mdadm
ok so i am trying to recover some data for a friend. what i am wanting to do is forcibly set up /dev/mdN to be a raid0 of /dev/sda and /dev/sdb i do not want to actually change any of the contents of these drives, just mount very simply as a raid0. the raid was originally created using an onboard nvidia raid on the motherboard these drives used to be hooked to. my friend thought he could shove them into another windows box (that is what he was running on them) and have windows recover the raid. all this did was totally destroy the superblock on one of the two drives. dmraid now wont see them as a matched pair so that is out. the actual data areas of both drives seems to be intact, but unless i can get them into raid0 i dont know how i can recover the data. it figures he gives me the drives after he makes it a notch or two more of a pain :\ now before the advent of mdadm i would use /etc/raidtab and have no issues setting up the raid device. as best i can tell i am using the correct commands for what i want but i pretty much get nothing but errors: [EMAIL PROTECTED]:/media# mdadm --build /dev/md1 --chunk=128 --level=0 --raid-devices=2 /dev/sda /dev/sdb mdadm: error opening /dev/md1: No such device or address [EMAIL PROTECTED]:/media# mdadm --build -n 2 -c 128 -l 0 /dev/md1 /dev/sda /dev/sdb mdadm: error opening /dev/md1: No such device or address when i run those commands i do get /dev/mdN entries created, but they do not point to a valid block device (as tested with fdisk -l and with dmraid -b) for the life of me i dont understand why anyone would put important data on a raid0, but that is what happened in this case. If i have to i will drop down to an older knoppix release to get raidtools back, as i have never had any issues in recovering crap onboard raid arrays nor windows software raid arrays under it. i am sure it can be done with mdadm but for the life of me i cannot seem to figure out exactly how. any help on this would be greatly appreciated Casey - To unsubscribe from this list: send the line unsubscribe linux-raid in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: raidtools to mdadm
On Sunday April 1, [EMAIL PROTECTED] wrote: as best i can tell i am using the correct commands for what i want but i pretty much get nothing but errors: [EMAIL PROTECTED]:/media# mdadm --build /dev/md1 --chunk=128 --level=0 --raid-devices=2 /dev/sda /dev/sdb mdadm: error opening /dev/md1: No such device or address No such device or address probably means that the md module is not loaded. modprobe md or modprobe md_mod and try again. NeilBrown - To unsubscribe from this list: send the line unsubscribe linux-raid in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: Changing partition types safe? raidtools to mdadm migration
On Thursday March 8, [EMAIL PROTECTED] wrote: So I should be safe in just removing the raidtools package and installing mdadm? Possibly. A significant difference is the way arrays are assembled at boot time. raidtools depended on raidstart (which never worked reliably and doesn't work at all with recent kernels) or type-FD partitions, which I assume you weren't using. mdadm has a lot more flexibility. You can still use type-FD partitions if you want, or you create /etc/mdadm.conf with roughly the output of mdadm -Ds though it is worth understanding the contents of that file and making sure it is what you want. NeilBrown - To unsubscribe from this list: send the line unsubscribe linux-raid in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
Changing partition types safe? raidtools to mdadm migration
I have a working RAID1 set. This is in a Gentoo system and I configured the RAID set using raidtools. I see that Raidtools are now deprecated in favor of mdadm. I installed mdadm, but it does not recognize my raid set. I tried the following command (note that my RAID set is active while I do this): $ mdadm /dev/md0 --query --detail This results in no output. I believe this is because I forgot to change the partition types on the partitions that make up the RAID set (/dev/sda1 and /dev/sdb1) to type fd (they are the default type 82). Can I safely change the partition types to fd on the partions that make up my RAID set? Or is there something else I should do to get mdadm to recognize my RAID set? Regards, Simon - To unsubscribe from this list: send the line unsubscribe linux-raid in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: Changing partition types safe? raidtools to mdadm migration
Neil, On 3/8/07, Neil Brown [EMAIL PROTECTED] wrote: On Thursday March 8, [EMAIL PROTECTED] wrote: I have a working RAID1 set. This is in a Gentoo system and I configured the RAID set using raidtools. I see that Raidtools are now deprecated in favor of mdadm. I installed mdadm, but it does not recognize my raid set. I tried the following command (note that my RAID set is active while I do this): $ mdadm /dev/md0 --query --detail Try mdadm --detail /dev/md0 Looks good: # mdadm --detail /dev/md0 /dev/md0: Version : 00.90.03 Creation Time : Sat Oct 15 16:20:52 2005 Raid Level : raid1 Array Size : 198153664 (188.97 GiB 202.91 GB) Used Dev Size : 198153664 (188.97 GiB 202.91 GB) Raid Devices : 2 Total Devices : 2 Preferred Minor : 0 Persistence : Superblock is persistent Update Time : Thu Mar 8 23:15:38 2007 State : clean Active Devices : 2 Working Devices : 2 Failed Devices : 0 Spare Devices : 0 UUID : de2ca4d0:7a3f6d57:d6751dc4:a51265e3 Events : 0.12491522 Number Major Minor RaidDevice State 0 8 180 active sync /dev/sdb2 If that doesn't work, what about cat /proc/mdadm This results in no output. I believe this is because I forgot to change the partition types on the partitions that make up the RAID set (/dev/sda1 and /dev/sdb1) to type fd (they are the default type 82). It has nothing to do with partition types. Can I safely change the partition types to fd on the partions that make up my RAID set? It is perfectly safe to change partition type. So I should be safe in just removing the raidtools package and installing mdadm? Regards, Simon - To unsubscribe from this list: send the line unsubscribe linux-raid in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
Re: Changing partition types safe? raidtools to mdadm migration
Neil, On 3/8/07, Simon Matthews [EMAIL PROTECTED] wrote: Number Major Minor RaidDevice State 0 8 180 active sync /dev/sdb2 I missed one line from the above: 1 821 active sync /dev/sda2 Simon - To unsubscribe from this list: send the line unsubscribe linux-raid in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
