Re: Not sure if this belongs here I'd like to ask

From: Robert Moir (bofh@mvps.org)
Date: 12/15/02 

From: "Robert Moir" <bofh@mvps.org>
Date: Sun, 15 Dec 2002 16:56:01 -0000

George Hester wrote:
> I tried starting my Windows 2000 Professional SP3 without connection
> to the NET to see if there were any call outs to the NET that would
> throw an error since there was no connection. Maybe not the best of
> tests but that's what I tried.
>
> Of course I got some DHCP errors in the event log. But one of them I
> wasn't to sure about. What the message said in essence is this:
>
> Unable to connect to a DHCP server for the IP address that was being
> used previously. So a new IP address has been assigned and it is
> 169.254.162.204. Now sure enough when I went to
> http://169.254.162.204 I got my localserver. That made sense but why
> this IP number? Why not 127.0.0.1?
>
> Anyway I put the NET connection back on and tried
> http://169.254.162.204 and got nothing. So I went to whois and found
> out this:
>
> OrgName: Internet Assigned Numbers Authority
> OrgID: IANA
>
> NetRange: 169.254.0.0 - 169.254.255.255
>
>
> CIDR: 169.254.0.0/16
>
> NetName: LINKLOCAL
> NetHandle: NET-169-254-0-0-1
> Parent: NET-169-0-0-0-0
> NetType: IANA Special Use
> NameServer: BLACKHOLE-1.IANA.ORG
> NameServer: BLACKHOLE-2.IANA.ORG
> Comment: Please see RFC 3330 for additional information.
> RegDate: 1998-01-27
> Updated: 2002-10-14
>
> I definitely do NOT like BLACKHOLE? Can anyone explain what's going
> on here? Thanks.

This is something called Automated Private IP addressing, that allows
machines set to use DHCP that cannot find a DHCP server to allocate their
own addresses from a range, as a sort of self-serve DHCP. The IP address
range is 169.254.0.1 through 169.254.255.254 and it's been reserved for
precisely this sort of thing in the IP routing standards which is why it
shows up as allocated that way.

It's designed so that machines on a LAN can still boot up and see one
another in the event of a DHCP server problem, and once you know what it
means its quite a handy diagnostic tool on a large lan; when you see it you
know that the local DHCP stuff is working but either the DHCP server or the
connection to it from the current machine of interest is broke.

http://www.win2000mag.com/Articles/Index.cfm?ArticleID=7464 has a fairly
good explanation.

Rob
MS MVP

Relevant Pages

  • Re: XP DNS problem
    ... seem to lose connection with the outside world. ... This is setup correctly in our DHCP server, ... Only the XP machines seem to suffer this problem. ... but if there is a rogue DHCP server on the ...
    (microsoft.public.windowsxp.network_web)
  • Re: Samba wont dance (more info)
    ... So the windows box refused the connection. ... wireless Linksys router, so it gets its outside address direct from my ISP ... act as a DHCP server - my machines in the basement are plugged directly into ...
    (Fedora)
  • Re: Networking 2 Laptops With Crossover Cable
    ... Both machines are running Windows XP ... there is a new connection, they both attempt to acquire an IP address ... from a DHCP server. ...
    (microsoft.public.windowsxp.help_and_support)
  • Re: XP DNS problem
    ... This is setup correctly in our DHCP server, ... I've never heard of dhcpfind.exe, but if there is a rogue DHCP server on the network and some machines are picking up bad configs from it, the way to identify it is to go to a machine which HAS picked up a bad config, and then look at the connection properties. ...
    (microsoft.public.windowsxp.network_web)
  • Re: D-Link Modem Not Working With One Computer
    ... defaults to when it cannot connect with the dhcp server. ... You say the settings are the same on the working and not working ... Networks" in Network Connections, but what is strange is that my ISP told me ... Control Panel: Network Connections: Wireless Network Connection: General ...
    (microsoft.public.windowsxp.network_web)