Fedora Core 6 hangs at shutdown on "Synchronizing SCSI cache" with iSCSI

linux=future · 08-15-2008, 09:09 AM

Hello all,

I have a box running Fedora Core 6, attached to a storage array via an ethernet cable. The two communicate via iSCSI. The problem is simple, but I can't think of a solution. At shutdown, Fedora stops eth0, which effectively terminates the iSCSI connection. However, it needs this connection to sync SCSI. I need Fedora to sync before shutting down eth0. Otherwise, the system hangs, and a hard reset is required.

ppesci · 08-15-2008, 10:40 PM

I think you can change the shutdown sequence to flush cache before eth0 down.

Anyway, FC6 is outdated. I suggest you update at least to F8

HTH

SteveK1979 · 08-16-2008, 08:08 AM

Exactly, make sure network is shutdown after the sync.

Personally I would look at moving when the network kill scripts run rather than anything else.

I don't believe there is any may to do this other than changing the order that the scripts run either. Anyway, it's pretty easy to change the order, and make sure you've got a backup!

Cheers,
Steve

linux=future · 08-16-2008, 03:24 PM

In a very odd twist, it seems that several other people have the same problem as me, and they started a thread a few hours later on Google groups: http://groups.google.com/group/open-...fae3dfb6e6c68f

I don't think it's possible to put the shutdown of eth* devices after the sync. The sync is done not by shutdown scripts, but by the kernel itself right before restart. Maybe I'm wrong about that, but the words "Syncing" are not in any rc* scripts, with the exception of the system clock.

At the end of the thread I linked to, there is a patch which supposedly fixes the problem. Thanks for the help, though!

Quote:

Anyway, FC6 is outdated. I suggest you update at least to F8

The only thing that keeps me from doing this is fear. I have very bad luck with yum upgrade, and a reformat would make a number of people (including my bosses) unhappy.

SteveK1979 · 08-16-2008, 06:52 PM

ah, of course I see what you mean now.

I think RHEL has it set up differently. Glad you got your issue sorted!

cheers,
Steve

ppesci · 08-17-2008, 11:47 AM

Do not perform yum upgrade, do a clean install, and yes, I know about upgrade problems using yum because I had it.

Maybe you can atach a new disk to the server and install a more up to gate fedora version. If your server has a recent bios, you can start from USB drive or stick. F9 allows you to install it in USB drive with no destructive way (that is, you do not erase anything).

HTH