Known Problems and Workarounds

Usage of an alternative configuration directory is different in mkbackup or recover mode

Using rear -v -c /etc/rear/mydir mkbackup works fine in production, but when you try (once booted from rescue image) rear -v -c /etc/rear/mydir recover it will fail.

Do the following in recover mode

The configuration files are copied to /etc/rear/ into the rescue image, so you need to type: rear -v recover

See issue #512

Is there a possibility to add btrfs subvolume to a rsync backup

  • Workaround: At present (release 1.18) there is no workaround in place. If you happen to know how this could be fixed then add your ideas to issue #417

UEFI ISO booting does not work on openSUSE 12.x, or SLES 11/12

  • Workaround: At present (release 1.18.x and higher) genisoimage cannot produce ISO images that can boot via UEFI on an openSUSE distribution (and also SLES). However, use the ebiso package instead to create UEFI ISO images on SLES.

System reconfiguration still has some weaknesses.

  • this has to be tested before relying on it, there are too many unknowns involved so that we cannot guarantee anything in this area. It has been developed mostly as a P2V tool to migrate HP servers to VMware Vms

  • hard disks need to be at least of the same size and amount as in the original system, ATM this is a simple 1:1 mapping of old to new disks, there is no removal of RAID groups or merging of smaller disks onto a bigger one or making stuff smaller.

  • any use of /dev/disk/by-path or /dev/disk/by-id is untested and will most likely not work. In some cases Relax-and-Recover will print a warning, but we are not able to detect all cases. Typically this leads to unbootable systems or bad /etc/fstab files

If SELinux is not disabled during backup (variable

BACKUP_SELINUX_DISABLE= in /etc/rear/local.conf) then we might see errors in the rear-$(hostname).log file such as:

tar: var/cache/yum/i386/15/updates/packages: Cannot setfilecon: No such file or directory

  • Workaround: Make sure the BACKUP_URL destination understands extended attributes (CIFS is out of the question and NFS is problematic). When using local disks (or external USB devices) make sure the proper mount options are given in the BACKUP_OPTIONS variable, e.g.:

    BACKUP_OPTIONS="rw,relatime,seclabel,user_xattr,acl,barrier=1,data=ordered"

Note

BACKUP_SELINUX_DISABLE=1 variable has been introduced in the /usr/share/rear/conf/default.conf file to disable SELinux while the backup is running (default setting).

ERROR: FindStorageDrivers called but STORAGE_DRIVERS is empty

Above error message might be seen after a fresh installation of the GNU/Linux kernel. ReaR got confused between the running kernel version number and the actual fresh kernel available.

  • Workaround: Reboot your server before using ReaR again, which is a good practice anyway after upgrading the GNU/Linux kernel.