[OpenAFS] Issue with immutable /usr

[Jon Stanley]

In the default configuration of OpenAFS as shipped (1.6.7), the
systemd unit file attempts to edit /usr/vice/etc/CellServDB. In a new
method of OS deployment, called rpm-ostree[1], the /usr namespace is
completely immutable and versioned. FHS also dictates that services
are not to make changes in /usr (though with the FHS being in a bit of
flux, I can't actually see the standard anywhere to cite it).

My suggestion would be to put the CellServDB (and other host-specific
OpenAFS configurations) into /etc.

-bash-4.2# systemctl status openafs-client.service
openafs-client.service - OpenAFS Client Service
   Loaded: loaded (/usr/lib/systemd/system/openafs-client.service; enabled)
   Active: failed (Result: exit-code) since Sun 2014-05-04 17:01:24
UTC; 5min ago
  Process: 436 ExecStartPre=/bin/sed -n w/usr/vice/etc/CellServDB
/usr/vice/etc/CellServDB.local /usr/vice/etc/CellServDB.dist
(code=exited, status=4)

May 04 17:01:24 localhost sed[436]: /bin/sed: couldn't open file
/usr/vice/etc/CellServDB: Read-only file system
May 04 17:01:24 localhost systemd[1]: openafs-client.service: control
process exited, code=exited status=4
May 04 17:01:24 localhost systemd[1]: Failed to start OpenAFS Client Service.
May 04 17:01:24 localhost systemd[1]: Unit openafs-client.service
entered failed state.

[1] http://www.projectatomic.io/docs/os-updates/

Thanks!
-Jon