Server 2003 SP1 - 2 NICs / random connection loss

I'm running Server 2003 web edition on a server with 2 nics, in a datacenter
where I have 2 IPs allocated on the same subnet with the same default gateway
address. Each Nic is assigned it's own IP address - all other network parms
are set up the same on both nics (DNS / Default Gateway).

After a few days, I started getting random connection loss on one Nic at a
time - never both. In some cases, the connection will restore itself, then
the other nic might go down - or possibly the same one again. Seemingly
random. Disabling & re-Enabling the Nic brings it back online - for a while
at least.

After searching for a while, I discovered another symptom - when I lose my
connection, if I do an ipconfig /all, the disconnected Nic shows a blank
default gateway.

I have read all the posts about how having 2 default gateways is not
recommended, and it is probably at the root of the problem here - what I
haven't found is a clear explaination of how to work around it.

If I remove the default gateway from one of the Nics, everything seems
stable, but I can't access the services on that Nic's IP. It seems the only
way I can have separate services running on different IPs, each assigned to a
different Nic, is with a default gateway entered for each one (the default
gateway is the same address on both Nics). But this clearly is causing a
problem.

Any advice on how to work around this is appreciated.

It is not recommended to use the same IP range on the mutilhomed computer. We do have a client who doesn't like Host header for his multiple web sites, so we help him to assign multiple IP addresses on one NIC. check this page,

ipconfig Or you can use ipconfig /all command to find the TCP/IP settings. ... Q: I have a windows server with just one NIC and have multiple public IPs for ...
www.howtonetworking.com/Networking/ipconfig.htm


Bob Lin, MS-MVP, MCSE & CNE
How to Setup Windows, Network, VPN & Remote Access on http://www.HowToNetworking.com
Networking, Internet, Routing, VPN Troubleshooting on http://www.ChicagoTech.net
"John Yeski" <(E-Mail Removed)> wrote in message news:82842678-4F81-4A03-B899-(E-Mail Removed)...
I'm running Server 2003 web edition on a server with 2 nics, in a datacenter
where I have 2 IPs allocated on the same subnet with the same default gateway
address. Each Nic is assigned it's own IP address - all other network parms
are set up the same on both nics (DNS / Default Gateway).

After a few days, I started getting random connection loss on one Nic at a
time - never both. In some cases, the connection will restore itself, then
the other nic might go down - or possibly the same one again. Seemingly
random. Disabling & re-Enabling the Nic brings it back online - for a while
at least.

After searching for a while, I discovered another symptom - when I lose my
connection, if I do an ipconfig /all, the disconnected Nic shows a blank
default gateway.

I have read all the posts about how having 2 default gateways is not
recommended, and it is probably at the root of the problem here - what I
haven't found is a clear explaination of how to work around it.

If I remove the default gateway from one of the Nics, everything seems
stable, but I can't access the services on that Nic's IP. It seems the only
way I can have separate services running on different IPs, each assigned to a
different Nic, is with a default gateway entered for each one (the default
gateway is the same address on both Nics). But this clearly is causing a
problem.

Any advice on how to work around this is appreciated.

If the recommendation is to assign the 2 IP addresses to the same Nic, is it
recommended that I try to set up teaming between the 2 Nics with both IPs
assigned to the team? It appears that my server (Dell Poweredge 750) will
support this. Currently, if one of the nics goes down, I can get into the
server remotely via the other. I'd like to keep the hardware redundancy.

Teaming is a new concept to me - not sure of the performance implications.
If you could point me in the direction of how to do that, it would be
appreciated.

Thanks again.


"Robert L [MS-MVP]" wrote:

> It is not recommended to use the same IP range on the mutilhomed computer. We do have a client who doesn't like Host header for his multiple web sites, so we help him to assign multiple IP addresses on one NIC. check this page,
>
> ipconfig Or you can use ipconfig /all command to find the TCP/IP settings. ... Q: I have a windows server with just one NIC and have multiple public IPs for ...
> www.howtonetworking.com/Networking/ipconfig.htm
>
>
> Bob Lin, MS-MVP, MCSE & CNE
> How to Setup Windows, Network, VPN & Remote Access on http://www.HowToNetworking.com
> Networking, Internet, Routing, VPN Troubleshooting on http://www.ChicagoTech.net
> "John Yeski" <(E-Mail Removed)> wrote in message news:82842678-4F81-4A03-B899-(E-Mail Removed)...
> I'm running Server 2003 web edition on a server with 2 nics, in a datacenter
> where I have 2 IPs allocated on the same subnet with the same default gateway
> address. Each Nic is assigned it's own IP address - all other network parms
> are set up the same on both nics (DNS / Default Gateway).
>
> After a few days, I started getting random connection loss on one Nic at a
> time - never both. In some cases, the connection will restore itself, then
> the other nic might go down - or possibly the same one again. Seemingly
> random. Disabling & re-Enabling the Nic brings it back online - for a while
> at least.
>
> After searching for a while, I discovered another symptom - when I lose my
> connection, if I do an ipconfig /all, the disconnected Nic shows a blank
> default gateway.
>
> I have read all the posts about how having 2 default gateways is not
> recommended, and it is probably at the root of the problem here - what I
> haven't found is a clear explaination of how to work around it.
>
> If I remove the default gateway from one of the Nics, everything seems
> stable, but I can't access the services on that Nic's IP. It seems the only
> way I can have separate services running on different IPs, each assigned to a
> different Nic, is with a default gateway entered for each one (the default
> gateway is the same address on both Nics). But this clearly is causing a
> problem.
>
> Any advice on how to work around this is appreciated