[OpenAFS] Some questions about AFS

Harald Barth haba@kth.se
Fri, 18 Jan 2008 16:02:29 +0100 (CET)


> my name is Anders Magnusson and I work at Lule} University in Sweden.

Hej Ragge!

> Test environment has been Heimdal 1.0 + OpenAFS 1.4.5, servers Redhat 4 (Dell 1950)
> and Solaris 10 (Sun V880).  Clients was Redhat and for Windows (using 1.5.28).

On Sol10, which file system do you have for /vicepX? I recommend
running the namei version of the server (which is not default to
historical reasons) because that makes it
underlying-file-system-agnostic.

> - What are the actual limitations on users/groups/volumes/sizes?  I'm interested in both
>   practical and theoretical.  I have tested with 200k volumes/partition, which seems to
>   work fine with the exception of that zapping volumes take 12 seconds each.
>   I also added 200k users and 200k groups, and tested access groups with 200k people
>   in each, without any noticeable slowdown.  Quite impressive :-)   I don't know if or how
>   any problem here should be noted.

2TB/volume and 2TB/partition, see recent emails on this list. We have
not seen any practical limitation in number of volumes and/or users
yet.

> - What are reasonable maximum on files/directory and mountpoints/directory? I tested by
>   adding 64k mountpoints (volumes) in one directory, and accessing directories below did
>   not become noticeably slower.  The only peculiarity I noted was that Windows explorer
>   only showed the first 1000 entries, but I don't know if it is a bug in explorer or the AFS client.

The only place where you want many mountpoints is /home and we have
solved that through /afs/pdc.kth.se/home/h/haba, others have used
/afs/kth.se/home/h/a/haba and so on.

> - A few problems with the windows manager tools were also noted, it may be just me that
>   haven't really understand how it all works :-)
>     In the server manager; running salvager failed with the error messages:
>        The AFS server manager was unable to perform the requested salvage operation.
>        Error: unable to successfully read log file (0x0000422A)

I think I can figure out what's wrong if you describe what you really tried to do :)

>   Also, moving volumes do not work, but I get no error message.  ``nothing happens''.

That is probably some setup error, but setup can be a bit hairy
because of the documentation that does not exist.

> I must say that we are all very impressed of how well it has worked so far!  Great!

*smile*

Harald.