I have been handed a ticket to work an RMA for a failed line card in a Cat6509-E. Not ever having worked with these devices before I had a few questions:

  • The config that applies to the ports on the failed line card, do those persist via the Supervisory modules?? Meaning, if we simply rip/replace with the RMA'd linecard the ports will reconfigure themselves as they were?

  • Are any commands required after swapping out the failed line card to bring the new card online to the system / restore configuration to those ports? If so, what are those?

Any other best practices when swapping line cards on the 6509-E you may have please feel free to share via comments. Finally - if the community feels this should be broken into separate Q's let me know and I will take care of it.

  • Make sure the DFC/memory are correct (especially on an XL card), this is an easy thing to overlook on a 6500 linecard and can have a major impact the card actually powering up, traffic through the card or the whole box.
    – cpt_fink
    Feb 17, 2015 at 7:52

1 Answer 1


A line card swap is exceedingly simple. You'll need to make sure that the replacement card is the exact same model as the old one. You can certainly bring TAC on the call with you to do the swap if you want help.

  • the configuration is saved in the running-config/startup-config, and will be applied to the new line card after your insert it and it boots up okay
  • no commands required after swapping the card. I would recommend a "copy run start" before starting.

A couple of caveats I've picked up through experience:

  • leave room in your management's mind for a whole switch reset. It's unlikely, but I've seen it happen.
  • if a tech is doing this for you remotely, log in via console to watch the proceedings. You'll also get to see all the log messages as the blade boots up.
  • never ever ever ever EVER leave a line card partially inserted*. Pull the old one completely out, put the new one completely in.

Of course, all of this will need to be done in a maintenance window. You should only expect traffic interruption on the line card in question, but leave yourself a "the switch might reset" clause in your maintenance window description.

Best of luck!

  • * I had a case once where a tech unlatched the line card and pulled it out slightly, then left it like that while he went to go get the replacement (10 minute walk). The Cat 6k line cards have two connections on the back. One is the data plane connection and allows data to flow to/from the card. The other goes in JUST before the first, and tells the switch "new card being inserted". The design intent is that when a card is inserted, the first connection stalls the backplane/bus until the second data connection is made. If the second connection never happens, the bus stays stalled. Whoops.
    – Keller G
    Feb 17, 2015 at 2:26
  • FYI, the bus stall issue is avoided if you're using DFCs; the bus only remains stalled for extended periods if events happen as you described Feb 17, 2015 at 4:55
  • Hey, old knowledge is old! Here's the appropriate link-rot-proof section from the link Mike provided.
    – Keller G
    Feb 17, 2015 at 7:51
  • The addition of a DFC module effectively disconnects a module from the Data Bus. As such, a DFC-enabled module is not subject to the bus stall mechanism that occurs when a module is inserted or removed from the chassis. Throughout these Online Insertion and Removal (OIR) events, the Data Bus is temporarily paused for just enough time to ensure that the insertion/removal process does not cause any data corruption on the backplane. This protection mechanism causes a very brief amount of packet loss. [..]. A module with a DFC onboard is not directly affected by this stall mechanism. [snip]
    – Keller G
    Feb 17, 2015 at 7:53
  • Thanks all for your input, sorry for the long delay in marking as answer!
    – A L
    Mar 30, 2015 at 20:02

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