Servers with two NICS and two networks

I have 8 servers with 100 desktops attached. The servers connect to a 1gb
switch that feeds all the desktops. There is a firewall attached to the
switch that provides Internet connection. All pretty standard stuff = IP is
10.10.1.0 to 10.10.5.0 with mask of 255.255.252.0.

I have a tape drive in one server that backs up data from the other servers.
Since all the servers have two NICs, I was hoping I could setup a separate
address range for those NICs and let the backup use that NIC and not flood
the other with traffic.

I can set the second NICs to be 172.16.1.1 – 172.16.1.250 range with mask of
255.255.255.0. I would put in a new 1gb switch that just connects the second
NICs (switch is cheap enough and no need to burden other switch with VLANs).

What would I need to also configure on the servers so it knows that traffic
destined for the other servers use the 172.16.x.x range and not the 10.10.x.x
range? What other settings do I need to know about?

Is this config going to make a difference in inter-server communication
(speed)?

"sverne" <> wrote in message
news8CBF50D-5798-4ECB-B278-...

> I have a tape drive in one server that backs up data from the other
> servers.
> Since all the servers have two NICs, I was hoping I could setup a separate
> address range for those NICs and let the backup use that NIC and not flood
> the other with traffic.

You are probably NOT going to flood the network in the first place,...so you
may be trying to solve an imaginary problem that does not exist. I have
been backing up over the LAN for years with no problem at all,...but it
probably helps that I have all the involved servers on the same Switch.

> I can set the second NICs to be 172.16.1.1 – 172.16.1.250 range with
> mask of
> 255.255.255.0. I would put in a new 1gb switch that just connects the
> second
> NICs (switch is cheap enough and no need to burden other switch with
> VLANs).
>
> What would I need to also configure on the servers so it knows that
> traffic
> destined for the other servers use the 172.16.x.x range and not the
> 10.10.x.x
> range? What other settings do I need to know about?

You have to use the IP#s ofr everything. If you use Names it will follow
the original Network Pathes.

However there are a slew of multi-homing issues with server,...particularly
Domain Controllers.

Here's the list of "evils":

157025 - Default Gateway Configuration for Multihomed Computers
http://support.microsoft.com/default...roduct=win2000

Default gateways
http://www.microsoft.com/technet/pro...d3859f5b1.mspx

Default Gateway Behavior for Windows TCP/IP
http://www.microsoft.com/technet/com...uy/cg0903.mspx

159168 - Multiple Default Gateways Can Cause Connectivity Problems
http://support.microsoft.com/kb/159168/EN-US/

Name resolution and connectivity issues on a Routing and Remote Access
Server that also runs DNS or WINS
http://support.microsoft.com/kb/292822/en-us

272294 - Active Directory Communication Fails on Multihomed Domain
Controllers
http://support.microsoft.com/default...b;en-us;272294

191611 - Symptoms of Multihomed Browsers
http://support.microsoft.com/default...b;EN-US;191611

Microsoft Windows XP - Multihoming Considerations
http://www.microsoft.com/resources/d..._tcp_qpzj.asp?


--
Phillip Windell

The views expressed, are my own and not those of my employer, or Microsoft,
or anyone else associated with me, including my cats.
-----------------------------------------------------

"Phillip Windell" <> wrote in message
news:%...
>
> "sverne" <> wrote in message
> news8CBF50D-5798-4ECB-B278-...
>
>> I have a tape drive in one server that backs up data from the other
>> servers.
>> Since all the servers have two NICs, I was hoping I could setup a
>> separate
>> address range for those NICs and let the backup use that NIC and not
>> flood
>> the other with traffic.
>
> You are probably NOT going to flood the network in the first place,...so
> you may be trying to solve an imaginary problem that does not exist. I
> have been backing up over the LAN for years with no problem at all,...but
> it probably helps that I have all the involved servers on the same Switch.
>
>> I can set the second NICs to be 172.16.1.1 – 172.16.1.250 range with
>> mask of
>> 255.255.255.0. I would put in a new 1gb switch that just connects the
>> second
>> NICs (switch is cheap enough and no need to burden other switch with
>> VLANs).
>>
>> What would I need to also configure on the servers so it knows that
>> traffic
>> destined for the other servers use the 172.16.x.x range and not the
>> 10.10.x.x
>> range? What other settings do I need to know about?
>
> You have to use the IP#s ofr everything. If you use Names it will follow
> the original Network Pathes.
>
> However there are a slew of multi-homing issues with
> server,...particularly Domain Controllers.
>
> Here's the list of "evils":
>
> 157025 - Default Gateway Configuration for Multihomed Computers
> http://support.microsoft.com/default...roduct=win2000
>
> Default gateways
> http://www.microsoft.com/technet/pro...d3859f5b1.mspx
>
> Default Gateway Behavior for Windows TCP/IP
> http://www.microsoft.com/technet/com...uy/cg0903.mspx
>
> 159168 - Multiple Default Gateways Can Cause Connectivity Problems
> http://support.microsoft.com/kb/159168/EN-US/
>
> Name resolution and connectivity issues on a Routing and Remote Access
> Server that also runs DNS or WINS
> http://support.microsoft.com/kb/292822/en-us
>
> 272294 - Active Directory Communication Fails on Multihomed Domain
> Controllers
> http://support.microsoft.com/default...b;en-us;272294
>
> 191611 - Symptoms of Multihomed Browsers
> http://support.microsoft.com/default...b;EN-US;191611
>
> Microsoft Windows XP - Multihoming Considerations
> http://www.microsoft.com/resources/d..._tcp_qpzj.asp?
>
>
> --
> Phillip Windell


Phil,

My blog has a compiled synopsis of multihomed domain controllers
(implications, why it happens and options to alter the DCs to make it work).
I hope the original poster, "sverne" finds it helpful.

Multihomed DCs with DNS, RRAS, multiple IPs, and/or PPPoE adapters
http://msmvps.com/blogs/acefekay/arc...-adapters.aspx


--
Ace

This posting is provided "AS-IS" with no warranties or guarantees and
confers no rights.

Please reply back to the newsgroup or forum for collaboration benefit among
responding engineers, and to help others benefit from your resolution.

Ace Fekay, MVP, MCT, MCITP EA, MCTS Windows 2008 & Exchange 2007, MCSE &
MCSA 2003/2000, MCSA Messaging 2003
Microsoft Certified Trainer
Microsoft MVP - Directory Services

If you feel this is an urgent issue and require immediate assistance, please
contact Microsoft PSS directly. Please check http://support.microsoft.com
for regional support phone numbers.

Yea, I need to add that link to my list and include it i posts like that.


--
Phillip Windell

The views expressed, are my own and not those of my employer, or Microsoft,
or anyone else associated with me, including my cats.
-----------------------------------------------------

"Phillip Windell" <> wrote in message
news:...
>
> Yea, I need to add that link to my list and include it i posts like that.
>
>
> --
> Phillip Windell
>
> The views expressed, are my own and not those of my employer, or
> Microsoft,
> or anyone else associated with me, including my cats.
> -----------------------------------------------------
>
>

Thanks. I may update it adding the links you supplied to the Related LInks
section. Thanks for posting those links, too. :-)

Ace

"Ace Fekay [MVP-DS, MCT]" <> wrote in message
news:...
> "Phillip Windell" <> wrote in message
> news:...
>>
>> Yea, I need to add that link to my list and include it i posts like that.
>>
>>
>> --
>> Phillip Windell
>>
>> The views expressed, are my own and not those of my employer, or
>> Microsoft,
>> or anyone else associated with me, including my cats.
>> -----------------------------------------------------
>>
>>
>
> Thanks. I may update it adding the links you supplied to the Related LInks
> section. Thanks for posting those links, too. :-)
>
> Ace
>
>
>

Getting back to the original post, I agree with Phillip. Having a
separate network for backup sounds like a good idea in theory, but it is a
headache in the real world. Like most apps, backup software likes to use
machine names not IP addresses. Making sure that it actually gets the
"right" IP address is always going to be a real pain. If it doesn't get the
"right" IP it is going to use the standard network anyway, even if you have
provided a second network.

Here's a few more that are "semi" related. They have to do with when you
might want multiple Default Gateways in a "correct" situation. Not saying
that I would like the scenario, but just being honest in that it does exist.

Load balance two Internet connections
http://www.geekswhoknow.com/articles...onnections.htm

128978 - Dead Gateway Detection in TCP/IP for Windows NT
http://support.microsoft.com/default...b;EN-US;128978

171564 - TCP/IP Dead Gateway Detection Algorithm Updated for Windows NT
http://support.microsoft.com/default...b;EN-US;171564


Then there is this one:

An explanation of the Automatic Metric feature for Internet Protocol routes
http://support.microsoft.com/?id=299540

People might find them useful I guess.
Some are old,..don't know when MS might rearange things and break the links.

--
Phillip Windell

The views expressed, are my own and not those of my employer, or Microsoft,
or anyone else associated with me, including my cats.
-----------------------------------------------------

"Phillip Windell" <> wrote in message
news:%...
> Here's a few more that are "semi" related. They have to do with when you
> might want multiple Default Gateways in a "correct" situation. Not saying
> that I would like the scenario, but just being honest in that it does
> exist.
>
> Load balance two Internet connections
> http://www.geekswhoknow.com/articles...onnections.htm
>
> 128978 - Dead Gateway Detection in TCP/IP for Windows NT
> http://support.microsoft.com/default...b;EN-US;128978
>
> 171564 - TCP/IP Dead Gateway Detection Algorithm Updated for Windows NT
> http://support.microsoft.com/default...b;EN-US;171564
>
>
> Then there is this one:
>
> An explanation of the Automatic Metric feature for Internet Protocol
> routes
> http://support.microsoft.com/?id=299540
>
> People might find them useful I guess.
> Some are old,..don't know when MS might rearange things and break the
> links.
>
> --
> Phillip Windell
>
> The views expressed, are my own and not those of my employer, or
> Microsoft,
> or anyone else associated with me, including my cats.
> -----------------------------------------------------
>

Some of them only apply to a non-server, such as 299540. That would be
helpful in those cases. I usually try to steer away from multihoming
anything unless I have to, but as a rule, never a DC.

Ace