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New Member

dns-server / dhcp cisco 1700


I wonder if i may run a few questions past you guys. We have a Cisco 1700 at one of our sites which is supposed to be managed but due to problems with the third party company i had to go there to perform some work.

I wanted to add in a dns server ip. Because i don't have the enable secret (Third PTY won't tell us) i used the break command normally used for password recovery. then once in used "copy start run".

Q. can i make config changes this way, save the changes then switch the config-register back and reload?

I managed to make the changes - Dhcp pool - dns-server ip's, right? changed the config-reg back and reloaded. No connectivity. anyway i messed around with different ip's eventually put it back to to original powered of for 5 mins and on again and it was ok.

Q: have i missed something out?

Q: could reloading or powering off and on to quickly affect thigs?

Q: Could the router be downloading it's config or something additional from a TFTP server? Is there anything i can check to confirm this on the config?

This is the dns part of the config all i want to do is change for 84.33, should be simple?

ip dhcp pool 0





lease infinite

Q: Is this part saying that and are not being used for dns?

no ip domain lookup

ip name-server

ip name-server

ip cef

no scripting tcl init

no scripting tcl encdir

Sorry i know thats long winded. Any help on any part of my problem would be much appreciated.

Kind regards

J mac

  • Other Network Infrastructure Subjects

Re: dns-server / dhcp cisco 1700


check for any lines starting with ´boot´ in the upper part of the configuration, it is very well possible that the router is configured to boot a specific file, or from a TFTP server.

Regarding the change of the DNS server IP address, in DHCP pool configuration mode, first delete the existing line:

no dns-server

and reenter it:


The DNS servers specified with the ´ip name-server´ command are used for non-DHCP clients.



New Member

Re: dns-server / dhcp cisco 1700

Thanks so much thats very helpful indeed.

New Member

Re: dns-server / dhcp cisco 1700


there are not any boot commands only the



Am i right in thinking i would see a boot command/s inside the markers and as i don't and "boot" is not mentioned anywhere else in the config that this router is using it's stored config and not getting one tftp'd.

Many thanks

J mac

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