Take the 2-minute tour ×
Server Fault is a question and answer site for professional system and network administrators. It's 100% free, no registration required.

I've got two internet gateways on my network. I want half the machines to point to the first Gateway and half to the second. Currently, they're all using DHCP.

I assume that to assign them to a specific gateway, I'll have to switch off DHCP and enter the gateway address manually.

Assuming this is the case - can someone provide a set of steps to do this?

share|improve this question
add comment

2 Answers 2

up vote 2 down vote accepted

Management of all those static IP's would be a pain. Have you considered splitting into two routed subnets, each with its own DHCP scope?

EG subnet1 is one one switch (or set of linked switches) and a router that connects to the internet. DHCP server is here.

Subnet2 on a different switch, or set of switches, whose router has one route/connection to subnet1, and another route/connection to the internet. On this router you can run a DHCP relay ('ip helper-address' if the switches are Cisco). If you used DHCP relay then your DHCP server in subnet1 would simply have abother scope, with its own address range and gateway settings. Alternatively you could just run another DHCP server in subnet2.

alt text

Note that this solution would require both routers having dual WAN links, OR a switch capable of VLANs. So it may not apply to you.

Caution: if you do this, your name services need to be in great condition all the time, since clients will no longer be able to fallback to broadcast name resolution if/when name services fail.

Alternatively you could go around setting static IP and gateway setting by hand or by script. Have a look at the NETSH commandline utility if you wish to script it. Example of a netsh command you'd run on each PC (changing the IP address each time):

netsh interface ip set address "NICname" static 192.168.20.101 255.255.255.0 192.168.20.1
                                                ^address       ^netmask      ^gateway
share|improve this answer
add comment

Having a DHCP server on your network is a good thing for guests and wifi laptops, but if you can avoid DHCP for your workstations, you'll have to make an adresse plan.
First you can share the both ISP connexions on your routeur to provide Load Balancing and/or Failover and remove one DHCP server, the resting one will make all your clients workstation go trought the reconfigured router.
Then you make your adress plan, it may for example be build on blocks of IP Adresses assigned to the various services like financial service, IT service, Executives etc.
When all your workstations have static IP adresses, you reconfigure your DHCP server with a IP subnet that will have a different firewall policy for the guests on your network and your wifi laptops (for them you can use DHCP reservations).
Hope this answer your question, you can go further by using different subnet masks and IP alias on the lan side of the firewall to isolate the differents blocks of you adress plan this can save you from using vlans providing IP settings on your workstations are not changeable by your users..
Hope this helps.

share|improve this answer
    
Got it - but once I've set the static IPs on the machines - how do I force them to use the non-DHCP router? –  Hawkeye Jun 22 '09 at 11:04
add comment

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.