Multihomed Servers Fail

[Luke Richey]

So far nobody has been able to figure this out.

This is started happening about 2 weeks ago for no reason.

We have 9 Windows 2000 Multihomed Servers (At several
locations) with all the latest patches, they are very
different in their configurations but for some reason all
three randomly will drop the static settings for one of
the network adapters (sometimes the same adapter
sometimes not) and there is no specific amount of time
until they do this, sometimes it is every 5 minutes,
sometimes every day.

This just started happening, after it happens one of the
NICS then has a 169.x.x.x IP address and a release and
renew on the DHCP based one will not work. We have to
manually reset the settings and then reboot! Then it will
only work for awhile.

We have tried installing different brands of NICS from
3COM, Intel and Linksys with old drivers and new drivers
with the same results

Each machine has virus packages that report clean (Three
different AV packages)

We tried DELETING the CONFIG area for the
HKLM\System\CurrentControlSet\Control\Network with no
luck after reboot. As soon as we reconfigured the NIC
with it's static IP the same problem started occuring.

I think I can safely assume:
1) This is not a driver problem
2) This is not a virus
3) The OS has a recent bug from some patch?

Example Systems

BUILDING 2, NETWORK 2

SERVER B
NIC 1 - Static 10.0.0.2
NIC 2 - 9 Static External IP Addresses

SERVER C
NIC 1 - Static 10.0.0.3
NIC 2 - Static External IP Address

BUILDING 1, NETWORK 1

SERVER A
NIC 1 - Static 10.0.0.2
NIC 2 - DHCP from Cable Modem

SERVER D
NIC 1 - Static 10.0.0.4
NIC 2 - Static External IP Address

SERVER E
NIC 1 - Static 10.0.0.5
NIC 2 - Static External IP Address

Any Ideas?

 

[Town Dummy]

Somebody didn't reset the permissions by accident did they?

 

[Guest]

On 9 different servers in 3 different companies? This
isn't a permissions issue when you set the IP address and
three seconds later it is no longer set, or 5 minutes
later, etc.

 

[Guest]

Well, even I’m facing a similar problem. I tried the same configuration with another test machine; it behaved exactly like the previous one. I guess if the configurations are alright, it might be a bug in the Windows 2000 Server. I’m also running 2 Linux machines (Eudora) in the same Network, with similar configuration (made to be members of multiple subnets), they are working really fine, without a hitch or a glitch.
It seems to be strange problem with Windows 2000 Advance Server DNS. I’m running an Active Directory integrated multihomed DNS server (with only one Ethernet Interface having additional IP addresses). The machine on which the DNS server is running is also a domain controller (root). This is required, because my network is divided into layer 2 switched VPN groups with different subnets (beginning from 172.16.0.0/24 to 172.16.10.0/24). Now, in order to make the DNS server member of each subnet I assigned additional IPs to the Ethernet Interface (starting from 172.16.0.1/24 to 172.16.10.1/24).
The host in the network receives IPs from the DHCP server (which is also running on the same machine as the DNS server). The hosts are assigned their respective DNS server IPs (say host in subnet 172.16.1.0/24 are assigned DNS server IPs as 172.16.1.1/24). The DHCP server is made to register the host name in the DNS server. There is no problem with the DHCP server, since everything is seems to be working fine.
The DNS server is listening on all the assigned IP addresses. I can even ping using the additional IPs (from the same machine), but hosts are unable to connect to the domain, because the additional IPs are not pointing to the DNS server. Moreover, if I reload the zone data, the additional IPs are registered (pointing to the DNS server - to itself), but they disappears when the DNS updates its records after 20 min. I tried putting TTL = 365 days for additional IPs, but it did not work.

ipconfig/all (at any instance) displays the following listing (it is static, additional IPs are always listed).
Windows 2000 IP Configuration
Host Name . . . . . . . . . . . . : dc-root
Primary DNS Suffix . . . . . . . : inet.kec
Node Type . . . . . . . . . . . . : Broadcast
IP Routing Enabled. . . . . . . . : No
WINS Proxy Enabled. . . . . . . . : No
DNS Suffix Search List. . . . . . : inet.kec
Ethernet adapter Local Area Connection:
Connection-specific DNS Suffix . :
Description . . . . . . . . . . . : Intel(R) 82540EM Based Network Connection
Physical Address. . . . . . . . . : 00-C0-9F-24-1D-3B
DHCP Enabled. . . . . . . . . . . : No
IP Address. . . . . . . . . . . . : 172.16.10.1
Subnet Mask . . . . . . . . . . . : 255.255.255.0
IP Address. . . . . . . . . . . . : 172.16.9.1
Subnet Mask . . . . . . . . . . . : 255.255.255.0
IP Address. . . . . . . . . . . . : 172.16.8.1
Subnet Mask . . . . . . . . . . . : 255.255.255.0
IP Address. . . . . . . . . . . . : 172.16.7.1
Subnet Mask . . . . . . . . . . . : 255.255.255.0
IP Address. . . . . . . . . . . . : 172.16.6.1
Subnet Mask . . . . . . . . . . . : 255.255.255.0
IP Address. . . . . . . . . . . . : 172.16.5.1
Subnet Mask . . . . . . . . . . . : 255.255.255.0
IP Address. . . . . . . . . . . . : 172.16.4.1
Subnet Mask . . . . . . . . . . . : 255.255.255.0
IP Address. . . . . . . . . . . . : 172.16.3.1
Subnet Mask . . . . . . . . . . . : 255.255.255.0
IP Address. . . . . . . . . . . . : 172.16.2.1
Subnet Mask . . . . . . . . . . . : 255.255.255.0
IP Address. . . . . . . . . . . . : 172.16.1.1
Subnet Mask . . . . . . . . . . . : 255.255.255.0
IP Address. . . . . . . . . . . . : 172.16.0.1
Subnet Mask . . . . . . . . . . . : 255.255.255.0
Default Gateway . . . . . . . . . : 172.16.0.21
DNS Servers . . . . . . . . . . . : 172.16.0.1
After I reload the DNS zone (or soon after I add the additional IPs pointing to the DNS server), nslookup displays the following result:
C:\>nslookup
Default Server: dc-root.inet.kec
Address: 172.16.0.1

dc-root

Server: dc-root.inet.kec
Address: 172.16.0.1
Name: dc-root.inet.kec
Addresses: 172.16.0.1, 172.16.1.1, 172.16.2.1, 172.16.3.1
172.16.4.1, 172.16.5.1, 172.16.6.1, 172.16.7.1, 172.16.8.1
172.16.9.1, 172.16.10.1

_

After approx 20 min, nslookup on dc-root lists the following result (note that additional IPs disappeared):
C:\>nslookup
Default Server: dc-root.inet.kec
Address: 172.16.0.1

dc-root

Server: dc-root.inet.kec
Address: 172.16.0.1
Name: dc-root.inet.kec
Address: 172.16.0.1

_

I,m wondering, what may be the problem. It seems the DNS server does not want to include the additional IPs. I even tried adding the IPs to the NS record also manually entered each IP pointing to the DNS server, it work for around 20 min. But soon after DNS updates its records, the additional IPs disappears.
Please help.
regards,
Rajesh