Cisco IOS reverted to previous version after reboot

[mburguk1000]

I have a ASA 5510 which was upgraded to version asa824-k8.bin from asa723-k8.bin and after reboot it has reverted to the old version

This may be because of Bootvar was not set ?  but if wanted to reload it back to most recent version I am just wondering if I am going to experience more issues as I know the Nat command syntax had changed and anything else

Any help will be greatly appreciated

[Marvin Rhoads]

If a boot variable is not set on an ASA, the system will load the first bootable ASA software image on disk0: during a reload.

You should always set the boot variable as a best practice - even if you only have one image.

NAT didn't change much if at all between 7.2(3) and 8.2(4) if I recall correctly. It's 8.3+ that changed the whole NAT syntax.

[Dru Goradia]

Do: sh run | i register

The config register should be 0x1

If it is other that 0x1, do:

conf t

config-register 0x1

Make sure to backup your config: more system:running-config

Then: reload