Why does the show compress command show software compression when hardware compression is enabled?
A. This can happen for a number of reasons: • If a link is in a shutdown state, issue the show compress command in order to show that it runs software compression. When the link comes up, it shows hardware compression. The command shows this because of the necessity to negotiate hardware compression, either through CCP for PPP, or through the FRF.9 process for Frame Relay. In order to run this negotiation, the link must not be shut down. • When you run hardware compression over PPP with some earlier versions of Cisco IOS software, do not type compress stac in order to issue the command, it is necessary to type ppp compress stac in order to issue the command. This is a holdover from an earlier command syntax. • In order to run hardware compression in a 7500 series router, the compression service adapter must be in the same VIP2 as the interface that is to be compressed. Interfaces on other VIP2s and on interface processor cards cannot communicate with the compression service adapters.
