Description of problem:
The cobbler logrotate config file needs the "missingok" keyword to suppress an
error from logrotate if no log files are present.

The keywords:

   rotate 4
   weekly

are also redundant since they are present in the system-default logrotate.conf,
so should be omitted in per-service files.  I suggest having:

/var/log/cobbler/cobblerd.log {
   missingok
   notifempty
   postrotate
      if [ -f /var/lock/subsys/cobblerd ]; then
         /etc/init.d/cobblerd restart
      fi
   endscript
}