Is CellServDB dynamicly read?

[Love]

Todd Cohen <cohentl at wckn.dorm.clarkson.edu> writes:

> All,
>   If I replace/modify CellServDB while Arla is running, will it
> automatically recognize the changes or do I need to kill arlad and
> restart?

You'll need to restart arlad or use fs newcell to update the incore
information.

The reson arla can't read the CellServDB is that is chroot()ed into the
cache-directory so it wont deadlock with other processes (that are wait for
arlad to serve the data).

A example of this are:

  - Lots a processes does lookups on /afs/e.kth.se/home.

  - For each process that does a lookup and arlad need to process the
   request, the parent is still held locked during reqiest.

  - Next process when the lock the parent higher up in the tree.

  - One of the processes will lock / to lookup "afs".

  - Now arlad tries to log to syslog that is busy or a fileserver have gone
    out on vaction. the libc code helpfully tries to open the syslog unix
    socket, to do that it needs to lock /

There is lots other of code in libc that does a lot of accesses.

we've talked about sending in a fd or fhandle to the CellServDB from a
outside process (fs forexample) to enable arla to read it.

Love