Upgrading Zeus software

These instructions describe how to upgrade the Zeus Traffic Manager or Zeus Load Balancer software. For instructions on upgrading Zeus Traffic Manager virtual appliances or hardware appliances, please see here, and for EC2, please see here.

You can upgrade a running copy of the Traffic Manager software with very little downtime. There are two ways to perform the upgrade: using the Administration Interface, or using the command line. The upgrade procedure:

1. Installs the new software into a different, version-controlled directory;
2. Copies the configuration from the running version of the software;
3. Stops the running software, swaps some symlinks and then starts the new software.

The downtime is rarely more than one or two seconds. If necessary, you can then install a new license key file using the Zeus Admin Server, for example, to enable new product features.

Upgrading your Zeus Traffic Manager software

Upgrading using the Administration Interface

1. Obtain the new installation package (ZeusTM_ProductVersion_OS.tgz);
2. Navigate to the System > Traffic Managers page on the Admin Interface of the Traffic Manager you intend to upgrade;
3. Click the Upgrade button and upload the new installation package;
4. Follow the instructions to apply the software upgrade.

Upgrading using the command line

1. Unpack your new software distribution file (ZeusTM_ProductVersion_OS.tgz) on the server.
2. Become root (assuming your existing installation is as root), and move into the directory that has just been created by extracting the distribution file.
3. Run the following command: ./zinstall. The upgrade program automatically stops your existing version of Zeus Traffic Manager, upgrades it, and restarts it, keeping all your existing configuration.

Upgrading a Cluster of Zeus Traffic Managers

If you have a cluster of traffic managers, you can upgrade each one in turn. Do not make any configuration changes until you have upgraded the entire cluster to the same software version.

To roll back to a previous software version

You can use the 'rollback' script to revert back to a previously installed version of Zeus software, or to roll forward to a later version that you installed previously:

• Become 'root' and run the ZEUSHOME/zxtm/bin/rollback.

You will then be shown a list of the different software versions that you have installed, and asked to chose which one you would like to roll back or forwards to. When you roll back (or forwards) to a different version, the software will use the configuration that was last active with that version.

For example, if you upgraded from version 5.1 to version 6.0 two weeks ago, then roll back to version 5.1, it will use the configuration that version 5.1 last used two weeks ago.

Notes and caveats for earlier releases

Rolling forwards from early versions of ZXTM (Zeus Traffic Manager)

Early versions of ZXTM did not include the rollback script. If the rollback script is not present, you can manually modify the zxtm, zxtmadmin and admin symlinks. The symlinks point to the current version of each software component.

• Stop the Zeus software using ZEUSHOME/stop-zeus
• Remove the zxtm, zxtmadmin and admin symlinks
• Recreate the symlinks:
  

  # ln -s zxtm-5.1 zxtm
  # ln -s zxtmadmin-5.1 zxtmadmin
  # ln -s admin-5.1 admin

• Start the Zeus software using ZEUSHOME/start-zeus

Upgrading to Zeus Traffic Manager 5.1r2 or earlier

When upgrading to ZXTM software version 5.1r2 or earlier, you should not skip version numbers; you must apply upgrade packages for each intervening major and minor version (but not maintenance 'r' releases). For example, to upgrade from version 4.2 to version 5.1r1, you should upgrade as follows: 4.2 -> 5.0r0 -> 5.1r1. This restriction does not apply for upgrades to Zeus Traffic Manager 6.0 or later.

Traffic IP Group issues when upgrading from version 4.1

If you have Traffic IP Groups using the 'keeptogether' flag that contain 'passive' machines, you should mark all machines as active before upgrading to ZXTM 4.2. Once the upgrade is complete, set these machines to 'passive' again.  Releases prior to 4.2 don't correctly handle the combination of keeptogether flag and passive machines, so leaving your configuration unchanged while upgrading may cause Traffic IP addresses to appear on multiple ZXTM machines.