Upgrade 7.2.4 to 8.0.4 Zero downtime

[Michael.Tuggle]

Has anyone performed a 7.2.4 upgrade to 8.0.4 with zero downtime? Here is the recommended upgrade paths from cisco about a major upgrade.

You can upgrade from the last minor release of the previous version to the next major release.

For example, you can upgrade from 7.9 to 8.0, assuming that 7.9 is the last minor version in the 7.x release.

Talking with Cisco Tech they said the upgrade could not be done using the zero downtime. Just wanted to check on others experiences with this upgrade.

[Matthew Warrick]

The issue is that you will not be able to sync firewalls with greatly differing versions hence you will not be able to maintain the connection state data after you upgrade one of the firewall pairs.

You can sync an 8.0(2) with an 8.0(4) firewall in my experience though so you would be able to perform a seamless upgrade in that situation. I have personally not tried to intentionally sync an 7.2(4) firewall with an 8.0(4) firewall. I wouldn't hold much hope for that working if Cisco already told you it is not supported.