Wheeler, JF (Jonathan) wrote: > One of our (3) AFS servers has a mounted read-write volume which must be > available 24x7 to our batch system. The server is as resilient is we > can make it, but still it may fail outside normal working hours for some > reason. For technical reasons related to the software installed on the > volume it is not possible to use read-only volumes mounted from our > other servers (the software must be installed and served from the same > directory name), so I have devised the following plan in the event of a > failure: > > a) create read-only volumes on the other 2 servers, but do not mount > them; use "vos release" whenever the software is updated > b) in the event of a failure of server1 (which has the rw volume), drop > the existing mount and mount one of the read-only volumes (we can live > with the read-only copy whilst server1 is being repaired/replaced) in > its place. > > Can anyone see problems with that scenario ? We could use "vos > convertROtoRW"; how would that affect the process ?
The problem with convertROtoRW is that a dying fileserver doesn't send callbacks to the client as would happen when you move the RW-volume to another place. So you will have to do a "fs checkvol" on all clients to make sure they don't wait forever for the broken server, but use instead the newly created RW-volume. Our backup strategy is completely based on the possibility to do convertROtoRW. CRON jobs on the batch worker do the "fs checkvol" once in a while... Hartmut > > Jonathan Wheeler > e-Science Centre > Rutherford Appleton Laboratory > > -- ----------------------------------------------------------------- Hartmut Reuter e-mail [email protected] phone +49-89-3299-1328 fax +49-89-3299-1301 RZG (Rechenzentrum Garching) web http://www.rzg.mpg.de/~hwr Computing Center of the Max-Planck-Gesellschaft (MPG) and the Institut fuer Plasmaphysik (IPP) ----------------------------------------------------------------- _______________________________________________ OpenAFS-info mailing list [email protected] https://lists.openafs.org/mailman/listinfo/openafs-info
