i dont think my raid worked :(

keegan · 01-07-2004, 12:15 PM

i tried to setup RAID1 in the redhat WS installation, but i dont think it worked.

i mounted my second harddrive, and there is a whole lotta free space on it, much more than on the 1st harddrive.

how can i fix it, or even see if it works...anyone know?

mcleodnine · 01-07-2004, 12:24 PM

software or hardware RAID?

keegan · 01-07-2004, 12:26 PM

sorry, software. i did it in the redhat installation. i think i put the swap drive back on hda, now that i think about it, linux wanted it on hdb. if thats the problem, well, i dont mind reinstalling. but i doubt thats it :-/

keegan · 01-07-2004, 01:27 PM

bump

mcleodnine · 01-07-2004, 01:52 PM

Pleas wait at least 24 hours before 'bump'ing a thread.

keegan · 01-07-2004, 02:04 PM

sorry. the dude at redhat sad it should be working fine becaus ei can see /dev/md0 mounted. hope it works.

mcleodnine · 01-07-2004, 02:12 PM

ok. let's see how you're partitioned and mounted.

post the results of 'fdisk -l' and 'mount' as well as 'cat /proc/mdstat'

which raid tools are you using? mdadm or raidtools? (if you used /etc/raidtab to setup then you're probably using raidtools)

keegan · 01-07-2004, 02:40 PM

here's my mount:

Code:

[root@rs-ylbih284vrrd root]# mount
/dev/md0 on / type ext3 (rw)
none on /proc type proc (rw)
usbdevfs on /proc/bus/usb type usbdevfs (rw)
/dev/hda1 on /boot type ext3 (rw)
none on /dev/pts type devpts (rw,gid=5,mode=620)
none on /dev/shm type tmpfs (rw)

Here's fdisk -l

Code:

[root@rs-ylbih284vrrd root]# fdisk -l
                                                                                
Disk /dev/hda: 81.9 GB, 81964302336 bytes
255 heads, 63 sectors/track, 9964 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
                                                                                
   Device Boot    Start       End    Blocks   Id  System
/dev/hda1   *         1        13    104391   83  Linux
/dev/hda2           144      9964  78887182+  fd  Linux raid autodetect
/dev/hda3            14       143   1044225   82  Linux swap
                                                                                
Partition table entries are not in disk order
                                                                                
Disk /dev/hdb: 81.9 GB, 81964302336 bytes
255 heads, 63 sectors/track, 9964 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
                                                                                
   Device Boot    Start       End    Blocks   Id  System
/dev/hdb1   *         1      9964  80035798+  fd  Linux raid autodetect

and here's my /proc/mdstat

Code:

[root@rs-ylbih284vrrd root]# cat /proc/mdstat
Personalities : [raid1]
read_ahead 1024 sectors
Event: 1
md0 : active raid1 hda2[0]
      78887104 blocks [2/1] [U_]
       
unused devices: <none>

I didnt use mdadm or raidtools; i set up raid1 when i installed redhat.

I just got off the phone with techsuport, i was concerned about not having my swap drive on the 2nd harddrive. he said that was ok, and i read him all the info you just asked form and he said my system was properly configured for Raid1.

However: i unplugged my main harddrive, put in a linux boot disk, and did a restore. It said it couldnt find any linux partitions, even thought the raid drive was still plugged in, albeit a slave. is that normal? is there something else i needed to do to access information?

mcleodnine · 01-07-2004, 02:49 PM

Code:

md0 : active raid1 hda2[0]
      78887104 blocks [2/1] [U_]

That's not good - it means that you are running a degraded array. For some reason you only have one drive (/dev/hda2) participating - the other isn't doing much.

let's get a look at 'cat /etc/raidtab'

keegan · 01-07-2004, 02:59 PM

Code:

[root@rs-ylbih284vrrd scratch]# cat /etc/raidtab
raiddev             /dev/md0
raid-level                  1
nr-raid-disks               2
chunk-size                  64k
persistent-superblock       1
nr-spare-disks              0
    device          /dev/hda2
    raid-disk     0
    device          /dev/hdb1
    raid-disk     1

I read the linux howtos after i installed linux, and they all say that's what the raidtab should look like. it displays both harddrives as being used.

mcleodnine · 01-07-2004, 03:12 PM

/etc/raidtab says that those are the drives that are being used to build the array, but /proc/mdstat says that you only have one drive active.

Try 'raidhotadd /dev/md0 /dev/hdb1'

keegan · 01-07-2004, 03:17 PM

Code:

[root@rs-ylbih284vrrd scratch]# cat /proc/mdstat
Personalities : [raid1]
read_ahead 1024 sectors
Event: 3
md0 : active raid1 hdb1[2] hda2[0]
      78887104 blocks [2/1] [U_]
      [>....................]  recovery =  0.0% (76232/78887104) finish=258.2min speed=5082K/sec
unused devices: <none>

258.2 minutes left. lol.

is there anything i'll need to do after that? Will this copy everything from hda over to hab?

thanks for your help!

mcleodnine · 01-07-2004, 03:21 PM

Quote:

Originally posted by keegan
258.2 minutes left. lol.

is there anything i'll need to do after that? Will this copy everything from hda over to hab?

thanks for your help!

Yes. don't use master/slave for RAID.

If this is for anything even remotely important then get your hands on a PCI ATA controller and use it instead.

keegan · 01-07-2004, 03:24 PM

hmm, i have one of those. Tomorrow morning i'll do it all over again.

Oh, and how did you know i was using master/slave instead of seperate ide cables?

oh, and one other question. since i'm redoing this, should i leave the swap drive on the 2nd harddrive? that doesnt make sense to me, if the 2nd harddrive fails, the first one wont have a swap. is it ook to keep it on the first drive?

mcleodnine · 01-07-2004, 03:32 PM

/dev/hda and /dev/hdb were kind of a giveaway

You can have swap on both if you want.

You might not have to do it all over again. You may be able to plunk the drives on the secondary and mess with raidtab a bit. It's at least worth a try and you can learn some fun stuff. If you get it right the first time you'll have saved lots of time and effort.