Cisco 827 refuses to save config, and a DNS issue

Posted on 2005-04-13
Last Modified: 2010-04-17
Hi all,

I've recently acquired a Cisco 827, unfortunately the damn thing always loses it's configuration every time the power goes off!!!
I have tried using the command "write mem" and it says that the config has been built OK, but after reboot it's still reset to default :-( So just what am I doing wrong???

And for bonus points, how can i make the router automatically pick up the DNS server address from my ISP when the PPP connects, and use it? Windows does this, so do most other routers, but with the 827 I have to use command ip name-server x.x.x.x as part of the config, which is no use if the ISP ever changes it...
Question by:Lostie
    LVL 13

    Accepted Solution

    Try issuing these commands before rebooting the router.

    config t
    config-register 0x2102

    LVL 28

    Assisted Solution

    Doesn't look like you can pick up the DNS server automatically. But it's not like ISPs change their DNS servers everyday...

    If you type show version on the router, the last line of the output tells you the configuration register. If it doesn't end in 02 then follow Dr-IPs advice above. If it does then it's another issue.
    LVL 1

    Author Comment

    Dr-IP: My configuration register (whatever that is) was set to "0x142", changing it to 0x2102 and re-writing config has solved the problem - this is brilliant, THANK YOU!

    mikebernhardt: If the 827 doesn't support it then I'll just have to live with it being static, you're right ISP is very unlikely to change it regularly, if at all - thanks for your advice.
    LVL 28

    Expert Comment

    0x42 tells the router not to boot from the config... you can save it all you want it will still boot up clean.
    LVL 13

    Expert Comment

    It's a common problem for with used Cisco routers. You would think that since they know how to change the setting to ignore the config so that you can get into a router you don’t know the password for. They would also know how to erase the old config and reset the setting back to the factory setting. It’s what I do when I get involved with selling used Cisco gear, and all it takes is an extra minute or two to do it right.    

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