ZFS: zpool scrub lockup

[Thomas Ronner]

Andriy Gapon wrote:

> For watchdog to fire it first needs to be enabled, e.g. by starting watchdogd.
> Try to run /etc/rd.d/watchdogd onestart before zfs start and then wait for about
> 16 seconds (default timeout).

I tried this. When only running 'watchdog' (without starting the daemon) 
it enters the debugger in 16 seconds. The only way to continue is 
issuing the 'watchdog' debugger command (I presume this disables the 
watchdog?), followed by 'c'.

But when re-enabling the watchdog by running /etc/rc.d/watchdogd start 
(I already added watchdogd to rc.conf)



> If that doesn't help, then it seems that the only option would be debugging via
> serial console. Or manually generating NMI, if your system has an NMI
> button/switch/jumper.

No, I don't have a manual NMI thingy.

Is this: 
http://www.freebsd.org/doc/en_US.ISO8859-1/books/developers-handbook/kerneldebug-online-gdb.html 
(10.6 On-Line Kernel Debugging Using Remote GDB) the debugging via 
serial console you're referring to?



Thanks,
Thomas