Topic: RAID 1 not work!

[yythoss]

Hello forum,

I have already discovered the problem on three servers.
After the SME is installed, I added a second disk (when turned off).
Afterwards via Admin console a RAID 1 created. After a few hours RAID's finished md0 and md1.
To check if the RAID also works, I shut down the server and replaced the disks.
sda becomes sdb and sdb becomes sda. The server does not boot anymore.
It shows up to the prompt of grub.
When trying to play a boot image via Rescue, it is said that there is no Linux partition on the disk.
What is wrong? That was never a problem with SME8.

[Stefano]

the hd you added is new or are you reusing it?

[yythoss]

Both are new

[Stefano]

ok. looks like something isn't working as expected.. OW, grub is not correctly installed on the new disk ('m guessing, BTW)
Please check bugzilla if is there already a bug for it or open a new one giving all the details, thank you

[yythoss]

No Help?

[yythoss]

I installed grub with this HowTo and I have the same problem:

https://wiki.contribs.org/Raid:Manual_Rebuild

[Stefano]

don't play with your server if it's a production one.
Please go to bugzilla, thank you

[byte]

Are the drives the same size?

[yythoss]

Yes, both WD RED 2TB

[byte]

Sounds like you could be experiencing this issue:

https://bugs.contribs.org/show_bug.cgi?id=9247

[yythoss]

No, that is not my problem.

[yythoss]

mdstat show this:

[root@server ~]# cat /proc/mdstat
Personalities : [raid1]
md0 : active raid1 sdb1[2] sda1[0]
      255936 blocks super 1.0 [2/2] [UU]

md1 : active raid1 sda2[0] sdb2[2]
      1953126400 blocks super 1.1 [2/2] [UU]
      bitmap: 3/15 pages [12KB], 65536KB chunk

unused devices: <none>


fdisk show this:

Good HDD:

Platte /dev/sda: 2000.4 GByte, 2000398934016 Byte
255 Köpfe, 63 Sektoren/Spur, 243201 Zylinder
Einheiten = Zylinder von 16065 × 512 = 8225280 Bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disk identifier: 0xf5ed110b

   Gerät  boot.     Anfang        Ende     Blöcke   Id  System
/dev/sda1   *           1          32      256000   fd  Linux raid autodetect
Partition 1 endet nicht an einer Zylindergrenze.
/dev/sda2              32      243202  1953257472   fd  Linux raid autodetect


Bad HDD:

Platte /dev/sdb: 2000.4 GByte, 2000398934016 Byte
255 Köpfe, 63 Sektoren/Spur, 243201 Zylinder
Einheiten = Zylinder von 16065 × 512 = 8225280 Bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disk identifier: 0x00000000

   Gerät  boot.     Anfang        Ende     Blöcke   Id  System
/dev/sdb1   *           1          32      256000+  fd  Linux raid autodetect
Partition 1 endet nicht an einer Zylindergrenze.
Partition 1 does not start on physical sector boundary.
/dev/sdb2              32      243202  1953258583   fd  Linux raid autodetect
Partition 2 does not start on physical sector boundary.

[yythoss]

I think the partions are the problem. So this is the problem why the rescue CD can't find a partition.

[janet]

yythoss

To check if the RAID also works, I shut down the server and replaced the disks.
sda becomes sdb and sdb becomes sda. The server does not boot anymore.
It shows up to the prompt of grub.

Please describe the above more fully & precisely.
If you replace both disks then of course there will be no grub, partition or data,  but I think you mean something else ie you only replace one disk.
Most new disks are formatted NTFS so you will still have to zero the MBR using dd command, before you use the disk.

[yythoss]

No, I replace both disks, not remove both disks.
The HDD's are fresh without any partition.

Now there is a new bug report:

https://bugs.contribs.org/show_bug.cgi?id=10562