That is a jump from 6 to 8. I suggest you read the docs very carefully on the upgrade proceudre, and some of the command syntax changes quite alot. There should be no issues with the upgrade - I have done a few and not had any issues yet!
There is a tool to convert from from pix to asa which is like v6 to v7/8 at the below link, I just you put your current config thru it just in case the upgrade does not go to plan:-
Totally agree with Andrew to go over the depricated commands.
Normally the upgrade takes care of the convertion on depricated statements and convert them to whichever equivalent is in newer codes.
Also if the worst happens what's the best way to get back to version 6.3 and restore the original config?
I would suggest as in any other mayor changes/upgrades like this one is to have a backout plan, such as backup your current configuration under 6.3 code and have handy the 6.3 code running on the PIX, you cannot backup the code but you should be able to download it from cisco..
backup the output of show version to have backups running activation keys. I believe the more backout analysis as well as implementation analysis of new code you can conduct the better your implementation will be.
there is a downgrade procedure but I have not seen a downgrade procedure straigh from 8.0 to 6., this backout procedure pertains to from 7.x back to 6.x.
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Question I am currently unable to specify "crypto keyring" command when
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