[OpenAFS-devel] How to know filesystems managed by AFS

[Harald Barth]

> I often get the problem to find out AFS managed
> UFS filesystems, 

Common misinterpretation: It's not an UFS filesystem. It's AFS.

> there is no info about the filesystems
> AFS sits on top of in neither the crash dumps itself,
> nor the /etc/mnttab or /etc/vfstab.

Are you talking about kernel panic dumps? The afs kernel module keeps
trace of the servers it's talking to. I guess that a crash dump from
a crashed afs client is only useful in combination with the matching
kernel module source.

The information in the mnttab and vfstab are just to make programs
happy who like to look at those files. The only valid information in
there is the mountpoint (/afs) and the filesystem type (afs).

> I'd really appreciate pointers to look at to
> find out a AFS configuration in terms of
> which AFS mountpoint/filesystem has which
> underlying real FS mountpoint/filesystem.

There is no direct relation between the /afs mountpoint and a
underlying filesystem. Where to find its volumes and files is figured
out by afs dynamically depending on the configuration in
/usr/vice/{CellServDB,ThisCell} and the data afs requests from the
fileservers and the volumeservers. The AFS filesystem is worldwide and
replicated. To give you just a glimpse from my laptop: (fs is an AFS
utility)

$ fs where /afs/cs.cmu.edu
File /afs/cs.cmu.edu is on hosts BLUEBERRY.SRV.CS.CMU.EDU PEACH.SRV.CS.CMU.EDU MANGO.SRV.CS.CMU.EDU BANANA.SRV.CS.CMU.EDU
$ fs where /afs/e.kth.se  
File /afs/e.kth.se is on hosts elektrien.e.kth.se basalt.e.kth.se pyrit.e.kth.se
$ fs where /afs/athena.mit.edu
File /afs/athena.mit.edu is on hosts HYDRA.MIT.EDU SCYLLA.MIT.EDU CHARYBDIS.MIT.EDU AJAX.MIT.EDU

A good starting point is http://www.openafs.org/. In the left lower
corner you will find the AFSLore Wiki which is part of the effors
to document things better than that they are now.

Harald.