Can anyone please advise if there are any differences in the ways which an ACE10 and ACE30 modules do load balancing - something which might affect http? In other words, if I do an upgrade from an ACE10 to ACE30, are there any configuration changes which should be done to make the ACE30 behave exactly the same as an ACE10?
The data plane is completely different : Intel IXP 2800 for ACE 10 / 20 and multiple Cavium Octeon chipsets for ACE 30.
ACE 30 is closer to the ACE 4710 than previous releases of ACE modules.
Just to finish up this thread, no there can be differences in behaviour between an ACE 10/20 and an ACE30 if you do a straight backup and restore to the newer ACE30. It is mainly due to the software on the ACE30, especially after A5(2.2). Cisco in a few cases made a decision to adhere more closely to the various RFCs and sometimes this can affect a badly coded website. Examples would be the maximum header length and accepted characters.
I saw a case where a badly written website used enormous headers and a command had to be added to allow the longer headers, also check out the parsing non-strict command here:
So it depends on the IOS version you upgrade to on your newer ACE30