Consistent file system hang with RELENG_6 of today ...
Marc G. Fournier
scrappy at hub.org
Sat Jul 30 03:49:14 GMT 2005
'k, this is turning out to be alot of fun ... the only machines I have
here that I can use to talk to the portmaster are Windows boxes ... can
you recommend a client for windows that would do good logging similar to
what 'script' does under FreeBSD? :(
On Fri, 29 Jul 2005, Robert Watson wrote:
> On Fri, 29 Jul 2005, Marc G. Fournier wrote:
>> Oh, before I forget ... how do you break to DDB from a serial console? I'll
>> be running a Portmaster for this ...
> Compile BREAK_TO_DEBUGGER into the kernel. Then issue a serial break and it
> should go into the debugger if the low-level console is set to the serial
> On my port-master, I issue a telnet break using "send break" after hitting ^]
> to generate a serial break for a serial port hooked up to TCP.
> There's also ALT_BREAK_TO_DEBUGGER, which is documented in NOTES, and
> provides for an alternative key sequence that doesn't use a break signal.
> Robert N M Watson
>> On Fri, 29 Jul 2005, Robert Watson wrote:
>>> On Thu, 28 Jul 2005, Marc G. Fournier wrote:
>>>> 'k, I'm starting to play with 6.x, for our new server ... my priority
>>>> right now is to just have it run the existing 'jail' environments from my
>>>> 4.x machine, while I work on getting all of our servers up to 6.x, and
>>>> then will worry about the jail's themselves ...
>>>> When I try and startup the 4.x jail on my 6.x machine, it "hangs" the
>>>> file system that the jail directory hierarchy happens to be mounted on
>>>> though ... twice in a row so far ...
>>>> Now, I'm suspecting (and am going to try without it) that it might be
>>>> because I'm mounting devfs within the 4.x jail, but even then, it
>>>> shouldn't hang things up, only generate a whack of errors ...
>>>> I have a good dump (CTL-ALT-ESC -> panic), but do not have a clue what to
>>>> offer from within there that might be of any use ...
>>>> If anyone is interested ... ?
>>> If you can get into DDB and have serial console output, the following
>>> would be useful:
>>> The output of 'show pcpu'
>>> The output of 'show pcpu X' for each present cpu, starting with 0.
>>> The output of 'ps'
>>> The output of 'trace' for the currently running thread, and each non-idle
>>> thread shown in the show pcpu output
>>> The output of 'show lockedvnods'
>>> It would also be useful if, relating to the startup of the jail, you can
>>> identify the point in the jail boot where it wedges, and if you hit
>>> Ctrl-T, what process is shown as running and what state it is in, and
>>> using DDB, trace that process.
>>> If you could show the trace output for each process listed in "show
>>> Likely, there is a leaked lock or a low buffer condition. However, once
>>> we have the above output we should be able to say more. The above will
>>> hopefully tell us whether it's a vnode deadlock, and ideally, the
>>> approximate source.
>>> Robert N M Watson
>> Marc G. Fournier Hub.Org Networking Services (http://www.hub.org)
>> Email: scrappy at hub.org Yahoo!: yscrappy ICQ: 7615664
Marc G. Fournier Hub.Org Networking Services (http://www.hub.org)
Email: scrappy at hub.org Yahoo!: yscrappy ICQ: 7615664
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