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New Member

12.4T CLI Backward compatibility

In my organization, we have migrated one of our test networks to 12.4T from 12.3

And we had been finding it hard to get all things up and running.

Is there any whitepaper on what has CLI have changed that are not backward compatible with 12.4 T ?

One of the issues was with NAT that I managed to resolve. Can u help with all others.. We got 100s of services running including QoS, VPNs.

Any help will be appreciated


Re: 12.4T CLI Backward compatibility

A multiprotocol BGP network is backwards compatible with a BGP network but BGP peers that do not support multiprotocol extensions cannot forward routing information, such as address family identifier information, that the multiprotocol extensions carry.

New Member

Re: 12.4T CLI Backward compatibility

I heard IP SLA doesnt work either

Super Bronze

Re: 12.4T CLI Backward compatibility

Normally, IOS handles upgrades, e.g. 12.3 to 12.4T, and changes syntax as necessary (although the converse can be a problem). Because of this, I haven't seen nice (e.g. side-by-side) documentation of CLI syntax changes between IOS versions.

Have you approached Cisco with the upgrade issues you're seeing?

New Member

Re: 12.4T CLI Backward compatibility

no, we are not trying to upgrade IOS directly, we want confirm the CLI changes.

1 by one all services will be migrated to a new router.

so I need service/policy based CLI changes that have been done in 12.4T