Cisco Cisco Email Security Appliance C190

From version 8.0 onwards, AsyncOS for Email is a 64-bit software. As a result of this changed memory 
model, the threshold values are revised in this release. Appliance enters resource conservation mode 
when the RAM utilization exceeds 45% and the allowed injection rate is gradually decreased as RAM 
utilization approaches 60%. This change does not affect the memory utilization on the appliance and all 
the components in the appliance continue to use the memory as earlier.

Appliances with large memory utilization, especially with large system quarantine, can enter resource 
conservation immediately after upgrading to AsyncOS 8.5 for Email. To avoid this scenario, make sure 
that you reduce the system quarantine to a few thousand messages before upgrading.

You can upgrade to release 8.5.0-473 from the following versions:

7.6.3-019 

7.8.0-360

8.0.1-023

To ensure a successful upgrade, you must complete some steps before you start the upgrade process. For 
details on these prerequisites, see 

.

Read through and consider the installation and upgrade impacts listed in this section. 

When you upgrade AsyncOS for Email from the web interface or Command Line Interface (CLI), the 
configuration is saved to file in the /configuration/upgrade directory. You can access the upgrade 
directory using an FTP client. Each configuration file name is appended with the version number, and 
passwords in the configuration file are masked so they are not human readable.

You must be logged in as the admin to upgrade. Also, you must reboot the appliance after upgrading.

If you are deploying a virtual appliance, see the Cisco Content Security Virtual Appliance Installation 
Guide. 

If you are switching from a physical appliance to a virtual appliance, you will need to convert your 
configuration file to an AsyncOS 8.0 virtual appliance configuration file. For information, see the 
Release Notes for Configuration Migration Tool 1.0 for Cisco Content Security Virtual Appliances. You 
can import the AsyncOS 8.0 virtual appliance configuration file into a virtual appliance running 
AsyncOS 8.5. 

Please contact Cisco TAC for information required to provision your virtual appliance.