[OpenAFS] Using TSM with AFS.

[Harald Barth]

> So the people now using TSM seems to do stuff like "vos dump" and store the dumps in TSM.

Yes. I use a modified adsmpipe which floated around (with a strange license). The folks at
HPC2N use their own tsmpipe (which has a good license) and I plan to change to that as soon
as I need to recompile. I think I should do that ASAP for Stacken anyway.

> But; we would like to do real volume backups in TSM and store
> generations of files etc, which seems to be quite difficult as it
> works right now.

Yes.

> So, I took a brief look at the TSM programmer's API, and it looks
> like it won't be too difficult to modify the "vos dump" stuff to
> cooperate with TSM to get it running. Actually, it looked so simple
> so I'm wondering what I can have missed :-) Hasn't someone done this
> before?

The API is only "strange", not difficult.

The "pipe" stuff has been done before. One program that accesses a
volume and compares the volume contents to something on TSM, and then
does dump/restore/copy/whatever I don't know about. This could be
solved in 2 steps:

1. Program that copies a volume from AFS space to TSM space and the
other way around. Here, only whole volumes are handled by TSM. If
you copy to TSM archive space you have to do the versioning yourself,
I use names like VOLUMENAME.00000000.20080131 for zero dumps and
VOLUMENAME.20080131.20080201 for incremental dumps. If you copy
to TSM file space, TSM will do the versioning for you, but I have
no idea how to handle incremental stuff this way. And the other way
around.

2. Program that actually takes a volume dump and stores its components
(files, ACLs etc) in TSM file space and the other way around. To do
this, one could use code from dumpscan.

tsmpipe: /afs/hpc2n.umu.se/lap/tsmpipe/x.x/src/dist
dumpscan: /afs/openafs.org/software/dumpscan/  

Harald.