SBS 2003 Multiple NICs with multiple ISPs


I have a SBS 2003 server. That server has six LAN connections, currently used 2. There are 3 ISP providers, three public IPs. DNS, DHCP runs on SBS server. Firewall is configured for failover in case ISP goes down.

How to configure LAN connections for the best network performance? Should I draw up a network map?
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adiloadiloConnect With a Mentor Commented:
enable network teaming if you have enough cables.
well sounds like you dont really need 6 lan connections from one server.
looks like the router is doing the work ie: sorting out DMZ's and surplus ISPs.
the only reason you could need more than 2 in a business function would be for clustering, ie: one live connection one for connection to other clusters and another one for redundancy.
maybe you need to explain a little more as to what you what to get out of your network?
Cris HannaConnect With a Mentor Commented:
SBS 2003 can only support 2 nics  One for the LAN, One for connection to the internet (but needs to be running through a firewall of some sort.   Either ISA 2004 if you have premium edition, or a hardware firewall.

Domain Controllers including SBS 2003 are not happy when they are multi-homed (multiple network connections on the LAN)   Nor should your WAN NIC have a public IP unless ISA is installed on SBS

If you do not have ISA 2004 you should consider only a SINGLE LAN NIC which is connected to a DUAL WAN router (for fail over) through the switch with all workstations
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kabixAuthor Commented:
Would this be correct?
Cris HannaConnect With a Mentor Commented:
The LAN and WAN NICs must be on different subnets


Is this server a VM?
kabixAuthor Commented:
Physical server.
Cris HannaCommented:
What other questions do you have?
As I've previously outlined
1.  SBS 2003 supports a max of two nics, so long as one is for the LAN subnet and one is for the WAN connection
2.  The new nics must be on different subnets
3.  To take advantange of multiple Internet providers, you will need a Dual WAN router.
4.  Multihoming LAN connections on a domain controller will cause problems and is not supported
CrisHanna_MVP is correct on all these points.  

I am also wondering what is the ultimate goal/question?
kabixAuthor Commented:
The ultimate goal is to make the network run fast. I just wanted to make sure that teaming and ip configurations would work.

I never dealt with teaming network cards. Don't really know if there would be network performance improvement with teamed nic cards on SBS 2003.
Cris HannaCommented:
There are many other limitations in your network that can affect speed
NIC cards and IP addressing is but one component

With SBS 2003 you're dealing with an OS that is now 8 years old...that by itself is a limiting factor because you are limited to about 3.5 GB of useable RAM

The Disk I/O could be a bottleneck
Network cabling could be an issue
The network switch could be an issue
Application compatibility could be an issue

Just having multiple nic cards and multiple IPs does not insure a fast network.

Unless you are doing HUGE CAD drawings which need to travel across network wires or LARGE database teaming will get you nothing

It certainly won't affect speed to the internet.

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