Changing the Base OS for SUSE Multi Linux Manager 5.1

SUSE Multi Linux Manager 5.1
SUSE Linux Micro 6.1
SUSE Linux Enterprise Server 15 SP7

IMPORTANT - This TID is specifically for SMLM5.1.  For SUMA5.0/SMLM5.0, see TID#000021804.

SMLM5.1 initially deployed on a SLM6.1 container host can be "migrated" to a SLES15SP7 container host.

This can be done by re-pointing the persistent storage data store (/var/lib/containers/storage/volumes/) from the SMLM5.1 instance running on the SLM6.1 container host to an instance running on a SLES15SP7 container host.

Example 1, useful in Hypervisor scenarios...
1. Assuming all channel sync is complete, shut down the SMLM5.1 container:
# mgradm stop
2. Make a note of the persistent storage entries from the SLM6.1 container host /etc/fstab, for example:
UUID=91ca0129-315b-4776-bb59-51c27833ff25 /var/lib/containers/storage/volumes xfs defaults,nofail 1 2
3. In the Hypervisor, detach the disk storage devices from the SLM6.1 container host VM and present them to the SLES15 SP7 container host VM.
4. Install and configure SLES15 SP7, ensuring the <fqdn> and IP match that of the original SLM6.1 container host.
5. Copy the persistent storage entries from the SLM6.1 container host /etc/fstab noted from above and apply to the SLES15 SP7 container host /etc/fstab

6. Deploy SMLM5.1 on SLES15SP7 as per the official SUSE documentation, ensuring the <fqdn> and IP are the same as that of the original SLM6.1 container host.

IMPORTANT: skip the mgr-storage-server section.  The installer will automatically detect and configure the persistent storage accordingly.  If mgr-storage-server is run, it may render the persistent storage unusable.

Example 2, useful for limited disk space/server instance scenarios...
1. Assuming all channel sync activity is complete, shut down the SMLM5.1 container:
# mgradm stop
2. Copy the contents of the persistent storage devices from the SLM6.1 container host to a temporary storage location, for example:
# rsync -Pav /var/lib/containers/storage/volumes/ <<temp_mount_point>>
3. Shut down the SMLM5.1 system:
# mgradm stop && shutdown -P
4. Install and configure SLES15SP7 as per the official SUSE documentation, ensuring the <fqdn> and IP are the same as that of the original SLM6.1 container host.
5. Deploy SUMA5.1 on the SLES15SP7 container host as per the official SUSE documentation.
6. Shut down the SUMA5.1 container:
# mgradm stop
7. Copy the contents of the <<temp_mount_point>> to the SLES15SP7 container host:
# rsync -Pav <<temp_mount_point>> root@<sles-fqdn>:/var/lib/containers/storage/volumes
8. Start SMLM5.1 on SLES:
# mgradm start

SMLM5.1 will automatically use the persistent storage accordingly.

These procedures are to be used as guidelines, as customer environments may differ in complexity.

IMPORTANT - This procedure has been tested moving persistent data stores from SMLM5.1 to SMLM5.1 instances.  Do not use it to move from SUMA 5.0.x to SMLM 5.1 instances, it will fail.

Please note the mgradm migrate command is for migrating SUMA4 to SMLM5, but will NOT migrate SMLM5 on SLEM to SMLM5 on SLES.

Also please note that while a subscription of SL Micro 6.1 is included with SMLM5, to run SMLM5 on SLES15SP7, a separate SLES15 subscription is required.