Dynamic DNS DDNS and 851w problem.

Answered Question
Aug 10th, 2008
User Badges:

I am trying to setup my 851 (C850-ADVSECURITYK9-M), Version 12.4(9)T7) with dynamic dns and I followed the cisco guide but for some reason "new pc" is being appended to my update. Instead of xxxx.homedns.org the router is updating newpc.xxxx.homedns.org. So it is updating the wrong entry, sorry if I am explaining this badly. My question is where is this "newpc" coming from? Here are my debug and configs. Thanks for the help!


Aug 11 02:23:10.291: DYNDNSUPD: Adding DNS mapping for newpc.xxxxxxx.homedns.org <=> xx.xx.xx.xx

Aug 11 02:23:10.291: HTTPDNS: Update add called for newpc.xxxxxx.homedns.org <=> xx.xx.xx.xx

*Aug 11 02:23:10.291: HTTPDNSUPD: URL = 'ht tp://username:[email protected]/nic/updatesystem=dyndns&hostname=xxxxxxx.homedns.org&myip=xx.xx.xx.xx/nic/updatesystem=dyndns&hostname=xxxxxxx.homedns.org&myip=xx.xx.xx.xx</A>'

*Aug 11 02:23:10.291: HTTPDNSUPD: Sending request

*Aug 11 02:23:10.383: HTTPDNSUPD: Response for update newpc.xxxxx.homedns.org <=> xx.xx.xx.xx

*Aug 11 02:23:10.383: HTTPDNSUPD: DATA START

*Aug 11 02:23:10.383: HTTPDNSUPD: DATA END, Status is Response data recieved, successfully


ip ddns update method sdm_ddns1


add ht tp://username:[email protected]/nic/updatesystem=dyndns&hostname=xxxxxx.homedns.org&myip/nic/updatesystem=dyndns&hostname=xxxxxx.homedns.org&myip< /A>=<a>

remove ht tp://username:[email protected]/nic/updatesystem=dyndns&hostname=xxxxx.homedns.org&myip=< a>


interface FastEthernet4

description $ETH-WAN$

ip dhcp client update dns server none

ip ddns update sdm_ddns1

ip ddns update hostname xxxxx.homedns.org

ip address dhcp client-id FastEthernet4

ip nat outside

ip virtual-reassembly

ip tcp adjust-mss 1460

duplex auto

speed auto

no cdp enable

  • 1
  • 2
  • 3
  • 4
  • 5
Overall Rating: 4 (1 ratings)
davex4285 Mon, 08/11/2008 - 13:11
User Badges:

Thanks for the help but even after the changes it still appends this "newpc" to my hostname.

So I did a DHCP debug to see what my ISP was setting and it looks like they are configuring my hostname as newpc.

*Aug 11 22:19:56.931: DHCP Ack Message

*Aug 11 22:19:56.931: DHCP: Lease Seconds: 900 Renewal secs: 450 Rebind secs: 787

*Aug 11 22:19:56.931: DHCP: Server ID Option:

*Aug 11 22:19:56.931: DHCP Host Name Option: newpc


is there anyway to over ride this?


This Discussion