Cisco Cisco Email Security Appliance C160 Mode D'Emploi

As a best practice, Cisco recommends preparing for an upgrade by taking the following steps. 

Save the XML configuration file off-box. If you need to revert to the pre-upgrade release for any reason, 
you will need this file. 

If you are using the Safelist/Blocklist feature, export the list off-box.

Suspend all listeners. If you perform the upgrade from the CLI, use the 

suspendlistener

 command. If 

you perform the upgrade from the GUI, listener suspension occurs automatically.

Wait for the queue to empty. You can use the 

workqueue

 command to view the number of messages in 

the work queue or the 

rate

 command in the CLI to monitor the message throughput on your appliance.

Re-enable the listeners post-upgrade.

You can download and install in a single operation, or download in the background and install later.

When downloading and upgrading AsyncOS in a single operation from a local server instead of from a 
Cisco IronPort server, the upgrade installs immediately while downloading. 
A banner displays for 10 seconds at the beginning of the upgrade process. While this banner is displayed, 
you have the option to type Control-C to exit the upgrade process before downloading starts. 

Choose whether you will download upgrades directly from Cisco or will host upgrade images from 
a server on your network. Then set up your network to support the method you choose. Then 
configure the appliance to obtain upgrades from your chosen source. See 

 and 

If you will install the upgrade now, follow the instructions in 

If you are installing the upgrade in a clustered system, see 

If you will only download the upgrade, there are no prerequisites until you are ready to install it. 

Choose System Administration > System Upgrade.