Section 7.2 NBAR bug?


Second time through this lab and I've come across a problem I dont remember getting first time around.

Creating a custom NBAR protocol for the marking and the router will not accept it:


Config on R4:

ip nbar custom r8 udp range 65001 65002

class-map match-all R8

SPRack1R4(config-cmap)#match protocol r8

% Incomplete command.


I can see the protocol in the NBAR mapping but the router just wont let me match it - any ideas whats going on here?


SPRack1R4(config-cmap)#match protocol r8 ?

% Unrecognized command


There isnt any option after that it wants.


R4 is running 12.3(14)T7 on Dynamips.


Any one else had this?


  • Hi,

    I have not run into this problem in the labs, but have always used a different naming convention.  However, I just tested it with your naming convention and got similar results. 

    ip nbar custom TEST udp 65001 65002
    ip nbar custom r8 udp 65003 65004

    class-map match-all TEST
     match protocol TEST

    r3(config-cmap)#match protocol ?
      TEST             User defined Protocol TEST
      aarp              AppleTalk ARP
      appletalk       AppleTalk
      arp               IP ARP

    You can see the r8 custom protocol doesnt even show up even though it is in the config...

    I am running a 3640 with 12.3(14)T7 for R4.  I also tried the command with and without the range command and got the same exact results.  If I use another name it is there and works just fine, so I would have to assume with your naming convention for your custom protocol you have found another great IOS feature! ;).  BTW, I also tested this on a 3845 with 12.4(19b) code and got the same exact results as with the 3640.  Both were on actual gear and not Dynamips.



  • Thanks Jeff


    I did go and try this using a longer custom name and lo and behold - it works as you stated!

    Good old IOS - at least I hit this prob now and not in Brussels :-)

  • Minimum length for protocol name in 12.4 is 4 characters. Try a longer name and it will work.

    In IOS 12.4 it will display an error message but in 12.3 it doesn't.


    Rack12R5(config)#ip nbar custom r8 udp range 65001 65002
    % NBAR ERROR: Name is shorter than minimum of 4 characters

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