[WBEL-users] Errors mounting raid device

[Tim Moore]

> If you have time, just some quick more questions. I started the array, then
> partitioned with fdisk (chosed primary, 1 partition 200Gb, type 83),
> rebooted.
> Checked fdisk printed the right partition, ok, I get /dev/md3p1 (means it is
> extended? I choosed a primary partition.....)

Does not look correct.  Unfortunately at the time I was working on a 
machine with both both hardware (3ware) and software raid, and gave a 
somewhat confusing reply.  Apologies.  Try the following and let me know if 
it works.

rgds,
tim.

SOFTWARE RAID
-------------
1. Configure kernel 'Multi-device support (RAID and LVM)' section.
2. Partition the physical disks that will make up the raid set as type 
'fd'.  Here is the machine I was working on:

# fdisk -l /dev/sda /dev/sdb

Disk /dev/sda: 255 heads, 63 sectors, 2501 cylinders
Units = cylinders of 16065 * 512 bytes

    Device Boot    Start       End    Blocks   Id  System
/dev/sda1   *         1        13    104391   83  Linux
/dev/sda2            14        45    257040   82  Linux swap
/dev/sda3            46      2500  19719787+   5  Extended
/dev/sda5            46       306   2096451   fd  Linux raid autodetect
/dev/sda6           307       457   1212876   fd  Linux raid autodetect
/dev/sda7           458      1248   6353676   fd  Linux raid autodetect
/dev/sda8          1249      2500  10056658+  fd  Linux raid autodetect

Disk /dev/sdb: 255 heads, 63 sectors, 2501 cylinders
Units = cylinders of 16065 * 512 bytes

    Device Boot    Start       End    Blocks   Id  System
/dev/sdb1   *         1        13    104391   83  Linux
/dev/sdb2            14        45    257040   82  Linux swap
/dev/sdb3            46      2500  19719787+   5  Extended
/dev/sdb5            46       306   2096451   fd  Linux raid autodetect
/dev/sdb6           307       457   1212876   fd  Linux raid autodetect
/dev/sdb7           458      1248   6353676   fd  Linux raid autodetect
/dev/sdb8          1249      2500  10056658+  fd  Linux raid autodetect

These partitions will be combined in /etc/raidtab to make up the md devices.

# cat /proc/mdstat
Personalities : [raid0] [raid1] [raid5]
read_ahead 1024 sectors
md0 : active raid0 sdb5[1] sda5[0]
       4192768 blocks 32k chunks

md1 : active raid0 sdb6[1] sda6[0]
       2425600 blocks 32k chunks

md2 : active raid0 sdb7[1] sda7[0]
       12707200 blocks 64k chunks

md3 : active raid0 sdb8[1] sda8[0]
       20113152 blocks 64k chunks

unused devices: <none>

3. Setup /etc/raidtab (use 'persistent-superblock 1'), run 'mkraid' and 
'raidstart', check /proc/mdstat.  It should look similar to the one above.

4. Make the filesystem on each /dev/md device.  For the following 
filesystem, the command was 'mke2fs -j -m0 -b4096 -L spare /dev/md4'.

# tune2fs -l /dev/md3
tune2fs 1.27 (8-Mar-2002)
Filesystem volume name:   spare
Last mounted on:          <not available>
Filesystem UUID:          1ed2818f-6dbe-491f-b120-ccf1f341e01f
Filesystem magic number:  0xEF53
Filesystem revision #:    1 (dynamic)
Filesystem features:      has_journal filetype needs_recovery sparse_super
Filesystem state:         clean
Errors behavior:          Continue
Filesystem OS type:       Linux
Inode count:              2518208
Block count:              5028288
Reserved block count:     0
Free blocks:              1336660
Free inodes:              2363764
First block:              0
Block size:               4096
Fragment size:            4096
Blocks per group:         32768
Fragments per group:      32768
Inodes per group:         16352
blocks per group:   511
Last mount time:          Tue Apr  6 07:27:07 2004
Last write time:          Tue Apr  6 07:27:07 2004
Mount count:              63
Maximum mount count:      -1
Last checked:             Fri Mar  5 10:52:00 2004
Check interval:           3888000 (1 month, 2 weeks, 1 day)
Next check after:         Mon Apr 19 11:52:00 2004
Reserved blocks uid:      0 (user root)
Reserved blocks gid:      0 (group root)
First inode:              11
Inode size:               128
Journal UUID:             <none>
Journal inode:            8
Journal device:           0x0000
First orphan inode:       0

5. Mount the /dev/md devices.  Here's the /etc/fstab entry for the above 
filesystem:

LABEL=spare  /spare  ext3  defaults,noatime,data=writeback  1 5