[LU-5863] Can't mount MGS due to label being less than 8 characters long.

• Type: Bug
• Resolution: Fixed
• Priority: Critical
• Fix Version/s: Lustre 2.7.0
• Affects Version/s: Lustre 2.7.0
• Labels: HB patch
• Severity: 3
• Assignee: James Nunez (Inactive)
• Reporter: James A Simmons

Description

The patch for LU-5383 fixed a out bound for ldd_svname. It test to see if ldd_svname is at least 8 characters in length but the function in lustre_disk.h server_make_name() sets ldd_svname for the mgs to MGS which is to short. This can prevent the MGS from mounting.

Issue Links

• is duplicated by: LU-5876 MGS volumes with short names do not mount since LU-5383 utils: fix array index out of bounds

Comments

[Jian Yu]

Hi James Simmons,
Are you going to add a regression test case into conf-sanity.sh or would you like me to do this?

[Andreas Dilger]

The patch fixes the core of the problem, but it doesn't add a test. Clearly, we need a conf-sanity test that formats a separate MGS and mounts it, since we can't possibly have had such a test if this bug slipped through.

[James Nunez (Inactive)]

Landed to master (pre-2.7)

[Cliff White (Inactive)]

And i have confirmed that we do NOT test internally with a separate MGS - so this was a complete escape.

[Cliff White (Inactive)]

And, I can't make a new clean filesystem, either. Hyperion is down
MGSNID="192.168.120.5@o2ib"
MGSDEV="/dev/mapper/iws10_4"
MDSDEV="/dev/mapper/iws10_1"
mkfs.lustre --reformat --mgs --device-size=$((512 * 1048576)) --fsname lustre $MGSDEV
mkfs.lustre --reformat --mdt --index=0 --mkfsoptions='-i 4096' --mgsnid=$MGSNID --device-size=$((2048 * 1048576)) --fsname lustre $MDSDEV

mkdir /mnt/mgs
mkdir /mnt/mds

mount -t lustre $MGSDEV /mnt/mgs
mount -t lustre $MDSDEV /mnt/mds
~
Fails with same error

[Cliff White (Inactive)]

This bug has stopped all testing on the stable filesystem, as the stable filesystem (formatted with older Lustre ) can no longer be mounted.
arg[4] = /dev/mapper/iws11_4
arg[5] = /mnt/mgs
source = /dev/mapper/iws11_4 (/dev/mapper/iws11_4), target = /mnt/mgs
options = rw
checking for existing Lustre data: found
Reading CONFIGS/mountdata
mount.lustre: invalid name 'MGS'

I really don't want to nuke the stable side, so a fix would be appreciated

[James Nunez (Inactive)]

Thanks for the patch, James.

[James A Simmons]

Patch to fix this is at http://review.whamcloud.com/#/c/12564. I think it shows up for previously formatted file systems.