[LU-7109] Update OST-index in IDIF inside osd-ldiskfs

• Type: Bug
• Resolution: Fixed
• Priority: Minor
• Fix Version/s: Lustre 2.8.0
• Severity: 3
• Assignee: nasf (Inactive)
• Reporter: nasf (Inactive)

Description

Old IDIF used "0" as the OST index, that may cause compatibility issues when update. There is switch inside osd-ldiskfs for controlling whether convert old IDIF to new one. Once the real OST index became part of the IDIF and stored on disk (in LMA EA), then the OST cannot be downgraded.

Because the conversion switch is inside osd-ldiskfs, the LFSCK should not update the IDIF-in-LMA, instead, leave it to be handled by OSD to avoid downgrading trouble.

Comments

[Joseph Gmitter (Inactive)]

Landed for 2.8

[Gerrit Updater]

Oleg Drokin ([e-mail]) merged in patch http://review.whamcloud.com/16282/
Subject: LU-7109 lfsck: update OST-index in IDIF inside OSD
Project: fs/lustre-release
Branch: master
Current Patch Set:
Commit: 140b897187cdbbdbc593b85dbb8a3322a9c28c9c

[nasf (Inactive)]

It is the OST's duty to decide whether the OST index is finally stored inside the IDIF-in-LMA, similar as "dirdata" feature. Once the feature of "OST index in IDIF-in-LMA" is enabled, then the on-disk format will be changed, and then the OST cannot be downgraded to old version. Current LFSCK will store the OST index in IDIF and update the LMA by force, such improper behaviour will affect the downgrade. As for memory corruption, I do NOT think there is any relationship.

[Andreas Dilger]

Fan Yong, what is the impact of this bug? Does the OSS or LFSCK crash or hang without the patch? Is there memory corruption?

[nasf (Inactive)]

Fan Yong ([e-mail]) uploaded a new patch: http://review.whamcloud.com/16282
Subject: LU-7109 lfsck: update OST-index in IDIF inside OSD
Project: fs/lustre-release
Branch: master
Current Patch Set: 2
Commit: de716e1c8c5daba240ef320f52cf5c5cfbf41ace