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dynamic DNS updates via DHCP server?

I have a 2801 router which I am using both for NAT/PAT & DHCP. I have searched unsuccessfully for information on what is required to forward lease assignments to a local DNS server to implement dynamic DNS.

Any information you can share would be greatly appreciated.


Re: dynamic DNS updates via DHCP server?

The DHCP server sends the update information to the DNM server, not the primary DNS server. The primary DNS

server retrieves this information from DNM via a zone transfer.

The DHCP server will keep an open connection between it and the DNM server so if that connection is not up the DHCP server will attempt to re-connect. If gives up after (I believe) 4 unsuccessful attempts. So if DNM is not accessible the DNS update info never gets sent.

The support for forwarding dynamic updates to DNS like a windows based DHCP server does not depend

on the IOS. You only need to use the following commands:

Router#config t

router(config)#int e0 (or the interface you are using)

#ip helper-address (here you have to place the address of the

external DCHP, the router must be able to ping this address)

#ip directed-broadcast

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