Hi (2010/06/04 23:18), Dejan Muhamedagic wrote: > Hi, > > On Fri, Jun 04, 2010 at 02:16:42PM +0200, Bernd Schubert wrote: >> On Friday 04 June 2010, Dejan Muhamedagic wrote: >>> Hi Takatoshi-san, >>> >>> On Fri, Jun 04, 2010 at 02:19:42PM +0900, Takatoshi MATSUO wrote: >>>> Hello >>>> >>>> I suggest to add a parameter which decides executing fsck >>>> as user's policy in Filesystem RA. >>>> >>>> Because, current RA dose not check ext3 because executing fsck depends on >>>> filesystem. >>>> But ext3 sometimes is broken and remounted read-only although it has >>>> journal, so >>> >>> Under which circumstances does this happen?
It happens when testing such as pulling disk cable, crashing OS, and so on. But I don't know detail circumstances because it's very very rare. Like Bernd says, no filesystem is perfect, and no hardware and no driver are perfect too. >> No filesystem is perfect ;) And any kind of hardware issue can cause >> filesystem and data corruption. > > Filesystem corruption? That's like not what I exactly had in mind :) > I'm not sure if fsck would help in that case anyway. Not saying > that that never happens (hw or bugs), but what I meant is > "normal" (say, on stonith) failovers where no fs corruption occurs. > >> Takatoshi-san, you should notice however, that for example e2fsck will start >> to run in non-auto mode, even if only a journal recovery is required. With >> default extX paramters, it then easily might perform a complete filesystem >> check, which might last hours. Not only that you might get unexpected long >> down time, you also need to be aware, that fsck time is often MUCH longer >> than >> the resource start timeout. If that happens, pacemaker will kill fsck in the >> middle of a run, which might damage your filesystem even more. I notice complete filesystem check, so if I use this parameter with force, I'll disable "max-mount-counts" and "time-last-checked" using tune2fs commands. But I don't notice pacemaker will kill fsck. >> That is all fine if you know about possible consequences, but I really doubt >> that most admins are aware of that. > > Most admins are not aware of most things ;-) > >>>> I want to decide myself executing fsck before mount to operate more >>>> safely. >>>> >>>> This new parameter has three mode "auto","force" and "no". >>>> Default is "auto" which do the same thing as before. >>>> "force" and "no" mean what they say. >>> >>> Patch applied. Many thanks! Thanks. >> That brings up and idea here, with extX, we could easily use >> >> dumpe2fs -h | grep "Filesystem state:" >> >> to check if fsck needs to be run. So the agent could refuse to mount the >> decide and make you run it manually in the foreground without any timeouts... >> I will implement that for our lustre_server agent (a heavily modified >> Filesystem agent) and then possibly back-port the patch. > > That may be a good idea. Given that one can say how long would > e2fsck take. It sounds good, but "dumpe2fs" is specific to ext2 and ext3. If killing fsck damages filesystem, can I rewrite this patch based on this idea? > Cheers, > > Dejan > >> Cheers, >> Bernd Regards. Takatoshi MATSUO _______________________________________________________ Linux-HA-Dev: [email protected] http://lists.linux-ha.org/mailman/listinfo/linux-ha-dev Home Page: http://linux-ha.org/
