[CentOS] reboot - is there a timeout on filesystem flush?

Wed Jan 7 16:32:28 UTC 2015
Steve Clark <sclark at netwolves.com>

On 01/07/2015 08:53 AM, Les Mikesell wrote:
> On Wed, Jan 7, 2015 at 12:10 AM, Keith Keller
> <kkeller at wombat.san-francisco.ca.us> wrote:
>> On 2015-01-07, Gordon Messmer <gordon.messmer at gmail.com> wrote:
>>> Of course, the other possibility is simply that you've formatted your
>>> own filesystems, and they have a maximum mount count or a check
>>> interval.
>> If Les is having to run fsck manually, as he wrote in his OP, then this
>> is unlikely to be the cause of the issues he described in that post.
>> There must be some sort of errors on the filesystem that caused the
>> unattended fsck to exit nonzero.
> Yes - the unattended fsck fails.   Personally, I'd prefer for the
> default run to use '-y' in the first place.  It's not like I'm more
> likely than fsck to know how to fix it and it is very inconvenient on
> remote machines.   The recent case was an opennms system updating a
> lot of rrd files, but I've also seen it on backuppc archives with lots
> of files and lots of hard links.  Some of these have been on VMware
> ESXi hosts where the physical host wasn't rebooted and the
> controller/power not involved at all.  Eventually these will be
> replaced with CentOS7 systems, probably using XFS but I don't know if
> that will be better or worse.   It is mostly on aging hardware, so it
> is possible that there are underlying controller issues.  I also see
> some rare cases on similar machines where a filesystem will go
> read-only with some scsi errors logged, but didn't look for that yet
> in this case.
I know that I have seen it take 10 ot 15 minutes to sync a 7200 rpm 3 TB WD drive that had over
2 million rrd files being updated by ntopng when the system had 32GB of ram. The system is a
Intel(R) Core(TM) i7-3770 CPU @ 3.40GHz but one cpu will in in constant IO wait state until the
sync finishes. I have never tried shutting it down when it was syncing though.

Stephen Clark
*NetWolves Managed Services, LLC.*
Director of Technology
Phone: 813-579-3200
Fax: 813-882-0209
Email: steve.clark at netwolves.com