Where can I find a backup? My own backup already contains the new version.
Backup is in /var/ipfire/backup/core...
But keep in mind that the grub is completly new, don't restore the backup, this will not boot because the kernel was changed.
There are only two entries after installation of the Update to 2.13 and a third with the pae kernel if pae is supported. The saved value was set to pae kernel. You should also use the pae if your board support it because some security features are only present in this kernel.
We suggest to not change the "default saved" in the grub.conf because we use this on kernel updates or feature changes add new pae-kernel.
If you want to force a kernel remotely change the save value to the new kernel
with "grub-set-default x" before you reboot.