Cisco 6500 Sup 2 MSFC2 re-appearing config

Posted on 2009-04-28
Last Modified: 2012-08-13

We have recently aquired a second-hand Cisco 6506 with a Sup2 and MFSC2 which is running IOS natively. It arrived with a config already preset which we considered odd at the time. Having had a look at It I think i can see why it arrived with a config present. It doesnt matter how many times I erase the startup-config, create another one, rewrite it back again etc etc, it still retains a good chunk of config including vlans in vtp mode, most annoying!

Looking at the file system, there's a whole chunk of files ive never had the pleasure of meeting before:


Im beginning to wonder if one of these files have a standard config in them which is always applied, acting almost as a factory default.

Before i get too heavy-handed with this lot and start breaking things, does anyone have any advice on how to tackle this?

Many thanks.
Question by:jackstark
    LVL 50

    Expert Comment

    by:Don Johnston
    If you do a "erase start" and then reload, it boots up with a configuration?

    Author Comment

    Yes that's right.
    LVL 50

    Accepted Solution

    Never run into that before.


    dir nvram:

    then delete each file. i.e.

    delete nvram:startup-config
    delete nvram:private-config

    then delete the vlan database

    delete const_nvram:vlan.dat


    Author Comment

    Thanks for the prompt replies. Before i dive in and start deleting, what are the implications of these files being removed, particularly private-config and underlying-config?

    LVL 50

    Expert Comment

    by:Don Johnston
    There won't be a configuration. :-)

    startup-config the simply the startup configuration.
    private-config is used to store things like crypto keys.
    vlan.dat is the vlan database file.

    Author Comment

    Thank you...

    and underlying-config?
    LVL 50

    Expert Comment

    by:Don Johnston

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