Disable DNS lookup in Cisco routers and switches
Submitted by Dharshin on Thu, 12/20/2007 - 05:04.
In privilege EXEC mode, when you type in something other than a Cisco command, the router assumes that you are typing a domain name and it tries to resolve what ever you type.
Although this feature is can be useful in some situations, for most of the time, this is a pain. The router becomes irresponsive for about 5-6 seconds trying to resolve the name.
R4#wrong-command Translating "wrong-command"...domain server (255.255.255.255) (255.255.255.255) Translating "wrong-command"...domain server (255.255.255.255) % Unknown command or computer name, or unable to find computer address R4#
To disable domain lookup type the commands as shown billow.
R4#conf t Enter configuration commands, one per line. End with CNTL/Z. R4(config)#no ip domain-lookup R4(config)#
Now the output is quick and router does not become irresponsive
R4#wrong-command Translating "wrong-command" Translating "wrong-command" % Unknown command or computer name, or unable to find computer address R4#
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Great site; however, there is no need to disable the DNS client. Just make sure you do not misspell anything... Just Kidding! If you have misspelled a command on the CLI the system attempts to make a telnet connection by first attempting a DNS lookup obviously. Having the DNS client is very useful and it is not necessary to disable it, it is just as easy to
CTRL+SHIFT+F6 then 6 and x
(Hold down the Control key (CTRL), SHIFT key, F6 key and 6 key at the same time, release then hit the x key)
hou01.agg01#exti
Translating "exti"...domain server (255.255.255.255) % Name lookup aborted
hou01.agg01#
There is no timing involved, and works with normal typing timing sequences.
This terminates a telnet session, and also actively aborts the DNS lookup
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Submitted by bg (not verified) on Wed, 07/02/2008 - 13:54.It’s a great website.Congrats.
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Submitted by dywan (not verified) on Fri, 05/16/2008 - 10:59.Very helpful artical! Thanks again.
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Submitted by suplementy (not verified) on Fri, 03/21/2008 - 08:50.I'd like to be able to find more of these helpful how-tos like disable dns here (thanks a lot for that) in your site
When I searched for Dharshin + "how to" in order to navigate within Dharshin to get to more cisco router stuff
1 the search failed to bring up anything
2 went out to google or the web when I wanted to search within Dharshin
3 cisco stuff - do you have a section or index on it
- if yes could you pls. provide an in-your face button/link to such
+ if no fair enough
How to configure logging synchronous in configuring a router not to interrupt typing up commands I cannot seem to get packet tracer to recognise this bloody command maybe its just pk
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Submitted by Simon (not verified) on Sun, 02/17/2008 - 17:50.Post new comment