When upgrading clustered ESAs, you must first disconnect the cluster so that all machines are running the exact same version. To upgrade, issue the upgrade command on each ESA and disconnect the cluster. After upgrading and rebooting all machines, use the clustercon g command to reconnect the cluster without needing to commit changes.

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Updated: December 8, 2014 Document ID: 118266
ESA FAQ: How do you upgrade an ESA that is in a cluster?
Contents
Introduction
Background Information
Upgrade ESAs in a Cluster
Introduction
This document describes how to upgrade the Cisco Email Security Appliances (ESAs) that run in a
cluster.
Background Information
When ESAs run in a cluster, they must all use the exact same AsyncOS version and build. If you desire
to upgrade the ESAs, you must rst disconnect the cluster. After all of the machines are upgraded,
you can reconnect the cluster via the clustercon g command.
Note: When the cluster is disconnected, it does not a ect the mail ow; however, any changes
that you make while the cluster is disconnected are not propagated to the other systems until
the reconnect is complete.
Upgrade ESAs in a Cluster
Note: You can perform the upgrade with the CLI or the GUI, but the reconnect clustercon g
commands are only available via the CLI. This document describes how to upgrade the
machines via the CLI.
Complete these steps in order to upgrade ESAs that run in a cluster via the CLI:
1. Enter the upgrade command into the CLI in order to upgrade AsyncOS to a newer
version. When you are asked whether you wish to disconnect the cluster, respond with the letter Y
in order to proceed:
(Machine host1.example.com)> upgrade
You must disconnect all machines in the cluster in order to upgrade them. D
to disconnect all machines in the cluster now? [Y]> Y

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2. Follow all of the upgrade prompts (reboot prompt included).
3. After all of the machines in the cluster are upgraded and rebooted, log onto a machine in the
cluster via the CLI and enter the clustercon g command.
4. Respond Yes in order to reconnect. It is not necessary to commit.
Choose the machine to reattach to the cluster. Separate multiple machines w
or specify a range with a dash.
1. host2.example.com (group Main)
2. host3.example.com (group Main)
3. host4.example.com (group Main)
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