em0 watchdog timeout 7-stable

[Greg Byshenk]

On Wed, May 13, 2009 at 06:42:07PM +0200, Greg Byshenk wrote:

> As a followup to my own previous message, I continue to have annoying 
> problems with "em?: watchdog timeout" on one of my machines (now running
> 7.2-STABLE as of 2009-05-08).
> 
> I have discontinued using the on-board (em, copper) NICs, and replaced
> the original fibre NIC with a newer model, but the problem persists.
> I've also set
> 
>    hw.pci.enable_msix=0
>    hw.pci.enable_msi=0
>    hw.em.rxd=1024
>    hw.em.txd=1024
>    net.inet.tcp.tso=0
> 
> ...as suggested in some discussions of this problem, and set the em1
> interface to 'polling', all to no avail.  Frequently, though irregularly
> (once or twice a day), the console begins to display
> 
>    em1: watchdog timeout -- resetting
>    em1: watchdog timeout -- resetting
>    em1: watchdog timeout -- resetting
> 
> the nework is down, and the machine locks up.
> 
> [Note: I am getting 'em1' now instead of 'em0' as previously, but this
> is due to changing all of the nics, which led to a different numbering;
> the timeout is still occurring on the (main) interface, the fibre 
> gigabit connection.]
> 
> What is particularly perverse (IMO) is that, since changing the NIC to
> the newer model (and updating the kernel), I can no longer break to the
> debugger when the lockup occurs (there is no response to the break) --
> bit I _can_ shut the machine down cleanly via hardware (a touch of the
> power switch sends 'shutdown', and the machine shuts down cleanly --
> after killing off processes waiting on network i/o).
> 
> The machine is running nfs and samba (3.2.10, from ports), and pretty
> much nothing else.
> 
> 
> Anyone have any ideas about this...?  I'm going mad with this.


Just as an FYI, the drive errors I described in my previous message
appear to have been due to a bad BBU on the RAID controller, and to
have been resolved.
 

-- 
greg byshenk  -  gbyshenk at byshenk.net  -  Leiden, NL