Migrating a Non-Global Zone to a Different Machine

About Migrating a Zone

The zonecfg and zoneadm commands can be used to migrate an existing non-global zone from one system to another. The zone is halted and detached from its current host. The zonepath is moved to the target host, where it is attached.

The following requirements apply to zone migration:

• You must remove all inactive BEs on the source system before migration.

• The global zone on the target system must be running the same Oracle Solaris 11 release as the original source host.

• To ensure that the zone will run properly, the target system must have the same or later versions of the required operating system packages as those installed on the original source host.

  Other packages, such as those for third-party products, can be different.

• If the new host has later versions of the zone-dependent packages, using zoneadm attach with the -u or -U options updates those packages within the zone to match the new host. The update on attach software looks at the zone that is being migrated and determines which packages must be updated to match the new host. Only those packages are updated. The rest of the packages can vary from zone to zone. Any packages installed inside the zone but not installed in the global zone are ignored and left as-is.

The zoneadm detach process creates the information necessary to attach the zone on a different system. The zoneadm attach process verifies that the target machine has the correct configuration to host the zone.

Because there are several ways to make the zonepath available on the new host, the actual movement of the zonepath from one system to another is a manual process that is performed by the global administrator.

When attached to the new system, the zone is in the installed state.

How to Migrate A Non-Global Zone Using ZFS Archives

You must be the global administrator or a user with appropriate authorizations in the global zone to perform this procedure.

This example describes how to create an archive of a zone and then attach that archive to another system. It assumes that the administrator on the source and target hosts are able to access a shared NFS server for temporary file storage. In the event that shared temporary space is not available, other means, such as scp secure copy, a remote file copy program, can be used to copy the files between the source and target machines. The scp program requests passwords or passphrases if they are needed for authentication.

1. Become an administrator.
2. Shut down the zone to be migrated, my-zone in this procedure.

   host1# zoneadm -z my-zone shutdown

3. (Optional) Detach the zone.

   host1# zoneadm -z my-zone detach

   The detached zone is now in the configured state. The zone will not automatically boot when the global zone next boots.

4. Export the zone configuration.

   host1# mkdir /net/server/zonearchives/my-zone
   host1# zonecfg -z my-zone export > /net/nserver/zonearchives/my-zone/my-zone.zonecfg

5. Create a gzip ZFS archive.

   host1# zfs list -H -o name /zones/my-zone
   rpool/zones/my-zone
   host1# zfs snapshot -r rpool/zones/my-zone@v2v
   host1# zfs send -rc rpool/zones/my-zone@v2v | gzip > /net/server/zonearchives/my-zone/my-zone.zfs.gz

   Use of compression is optional, but it is generally faster because less I/O is performed while writing and subsequently reading the archive. For more information, see Oracle Solaris Administration: ZFS File Systems.

6. On the new host, configure the zone.

   host2# zonecfg -z my-zone -f /net/server/zonearchives/my-zone/my-zone.zonecfg

   You will see the following system message:

   my-zone: No such zone configured
   Use 'create' to begin configuring a new zone.

7. To create the zone my-zone on the new host, use the zonecfg command with the -a option and the zonepath on the new host.

   zonecfg:my-zone> create -a /zones/my-zone

8. (Optional) View the configuration.

   zonecfg:my-zone> info
   zonename: my-zone
   zonepath: /zones/my-zone
   autoboot: false
   pool:
   net:
            address: 192.168.0.90
            physical: bge0

9. Make any required adjustments to the configuration.

   For example, the network physical device is different on the new host, or devices that are part of the configuration might have different names on the new host.

   zonecfg:my-zone> select net physical=bge0
   zonecfg:my-zone:net> set physical=e1000g0
   zonecfg:my-zone:net> end

10. Commit the configuration and exit.

    zonecfg:my-zone> commit
    zonecfg:my-zone> exit

11. Attach the zone to the new host by using one of the following methods.
    • Attach the zone without updating any software.

      host2# zoneadm -z my-zone attach -a /net/server/zonearchives/my-zone/my-zone.zfs.gz

    • Attach the zone, performing the minimum updates required to allow the attach to succeed:

      host2# zoneadm -z my-zone attach -u -a /net/server/zonearchives/my-zone/my-zone.zfs.gz

    • Attach the zone, updating all the software in the zone to the latest version that is compatible with the global zone.

      host2# zoneadm -z my-zone attach -U -a /net/server/zonearchives/my-zone/my-zone.zfs.gz

How to Move the zonepath to a new Host

There are many ways to create an archive of the zonepath. For example, you can use the zfs send, cpio, or pax commands described in the cpio(1), pax(1) and zfs(1M) man pages.

There are also several ways to transfer the archive to the new host. The mechanism used to transfer the zonepath from the source host to the target destination host depends on the local configuration. In some cases, such as a SAN, the zonepath data might not actually move. The SAN can simply be reconfigured to make the zonepath visible on the new host. In other cases, the zonepath might be written to tape, and the tape mailed to a new site.

For these reasons, this step is not automated. The system administrator must choose the most appropriate technique to move the zonepath to the new host.

1. Become an administrator.
2. Move the zonepath to the new host. You can use the method described in this procedure, or use another method of your choice.

Example 23-1 Archiving and Moving the zonepath Using the tar Command, and Attaching the Zone

1. Create a tar file of the zonepath on host1 and transfer it to host2 by using the sftp command.

   host1# cd /zones
   host1# tar cf my-zone.tar my-zone
   host1# sftp host2
   Connecting to host2...
   Password:
   sftp> cd /zones
   sftp> put my-zone.tar
   Uploading my-zone.tar to /zones/my-zone.tar
   sftp> quit

2. On host2, attach the zone:

   host2# zoneadm -z my-zone attach -a /zones/my-zone.tar -u

For more information, see sftp(1) and tar(1).

Example 23-2 Archiving the zonepath Using cpio and Compressing the Archive Using gzip

This is an alternative to using the tar command as shown in Example 23-1.

host1# zoneadm -z my-zone halt
host1# find my-zone -print | cpio -oP@/ | gzip > my-zone.cpio.gz

Next Steps

If you have used the -a option instead of reconfiguring a SAN, then the zonepath data will still be visible on the source host even though the zone is now in the configured state. You can either manually remove the zonepath from the source host after you have finished moving the data to the new host, or you can reattach the zone to the source host and use the zoneadm uninstall command to remove the zonepath.