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"?" for online help updates running config - ASA 8.4.5

Hello, Is this a Bug? Thanks.


This morning I was attempting to create a placeholder interface for VLAN 4050 in an ASA using Port-Channel8.4050. I wasn’t sure what subinterface range the ASA would accept so I typed:

ASA/act/pri(config)# interface port-channel 8.4050 ?

configure mode commands/options:


ASA/act/pri(config)# exit

I used the question mark as a confirmation that the ASA would accept “interface port-channel8.4050”, which it does, then I used the backspace key to delete the text “interface port-channel8.4050 ?” and exit configuration mode. This set of actions resulted in the ASA adding this to the running configuration:

interface Port-channel8.4050

no vlan

no nameif

no security-level

no ip address

None of these commands were written to TACACS+ command accounting. Weird, seems like a Defect. I suppose I’ll see if Cisco knows about this and report it if not. I suppose it could be expected behavior but I’ve never met a network device where typing “?” for online help resulted in adding to the running configuration.


Super Bronze

"?" for online help updates running config - ASA 8.4.5


I think you need to use the "?" in a different spot.

To know the Port-channel ID range you should use it right after "port-channel" I think.

You could then try to use the "?" after "interface port-channel 8.?" and see if it gives the subinterface ID range.

I am not 100% sure about the format.

With regards to the created interface, I think those are all the default settings of a subinterface on an ASA firewall so they are created when the interface is created. They arent however commands that you have input there youserlf but rather default settings the ASA generates I would assume.

- Jouni

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