[OpenAFS] Read-Write Disconnected Mode - How does it work?

[Jason Edgecombe]

Simon Wilkinson wrote:
>
> On 2 Feb 2009, at 01:48, Jason Edgecombe wrote:
>> I had some trouble with discon mode. I compiled an RPM from the 1_5
>> branch in CVS. I can "find . -type f | cat > /dev/null", then I can
>> fs discon offline. Problems that I had:
>> * ls couldn't find "."; reconnecting and disconnecting fixed it
>
> This suggests that you didn't cache the directory - either it was
> skipped by the find, or the callback on it had been expired by the
> time you went offline. Pinning should solve these kinds of issues.
>
>> * I tried running my newtests perl scripts, but that failed with some
>> perl errors.
>
> Were these issues related to the filesystem, or other problems? Are
> those tests available somewhere?
>
>> * vi complained of multiple swap files when trying to edit the config
>> file for my test suite.
>
> Odd. Can you get an fstrace log of what vi was trying to do when it
> complained - I can vi whilst disconnected without any problem.
>
>> * fs discon online said I didn't have the proper permissions when run
>> as root.
>
> Did you have tokens? The error code you're getting is UAEACCES, which
> suggests not.
>
>> * "fs discon online -force" made AFS freeze
>
> Again, strange. Did you get cmdebug -long output to see if it's hung
> on a lock, or alt-sysreq-t output to see where each process is blocked?
The tests are at
/afs/dementia.org/home/edgester/git/newtests/

I'm certain I had tokens. I'll have to try things again when I get home
this evening.

Pardon my ignorance, but how do I enable the fs trace log? Where will it be?
Can I trigger alt-sysreq-t remotely and get the output?

Thanks,
Jason