How do I setup the IP Class in order to make connectivity the most efficient ?

    I currently have a network of 10 NT Servers. Each server has 2 NIC's, 1 on a 172.17.x.x network for office connectivity and one on gigabit interfaces which sole function is to provide faster and more reliable connectivity between the servers, one of which is Oracle. The gigabit network will need at most 50 connections. This is a closed network with a simple gigabit switch linking the servers. I currently have this gigabit network setup as follows: address range should be between and, I have currently have no DNS servers on this network, all addresses are static, all addresses are referenced in each server's host file, and my current IP Mask is set to Is there a more efficient mask since I need only likely 25 addresses, 50 at most ever ? I may need to setup DNS on one of the servers and I assume that it'll be listening on both the 172 and 10 networks. Should I then list the DNS server statically, and register the 10.x addresses as well as the 172's. I aslo noticed on two machines (All of these are NT 2K Advanced), that internet connectivity was timing out most of the time on the 172 network, and after a route print, I saw that the first route in the list was 10.10.10.x network. I then executed a Route Delete and placed the 172 network as persistant and at the bigining of the list, but upon reboot, although the persistant route still shows as such, the 10.10.10.x route appears first, and Internet connectivity stalls once more. This is strange to me since only a couple of servers are experiencing this. Thoughts and suggestions are welcome. Basically, the 10.10.10.x closed network prevents Oracle from possibly losing data in any case that the 172 network or gateway goes down....


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You bring up some interesting discussion topics.

I'll start at the bottom because I like to work backwards.  You should not be having a default gateway configured for the NICs on the network.  Every computer should only have 1 default gateway.  This allows anything destined for an unknown network (internet), to be routed one particular way.  When you say that the route shows up first, do you mean for the network?  Cause if not, then the order of routes doesn't matter.  Your computer will jump down to the route that matches the correct network destination.

As far as using 50 computers, yes you can expand or shrink a network address scheme.  Its called subnetting and supernetting, but it doesn't lead to any performance increases or decreases if you are using static addressing.  When using DHCP, then having the correct number of available IP addresses in a scheme becomes important.  for less than 75 computers, its generally accepted that you can use a 24-bit mask, when would be a subnet mask of  giving you w.x.y.1 thru w.x.y.255.  you can always adjust the network later, although this becomes harder with static IP addresses.

Managing HOSTS files is messy for 50 computers.  It would be great to have a DNS server.  If you are using static IP addresses, then you will have to create static DNS records.  If all comptuers on the network have dual NICs, then I would have the DNS server listen only on the other network (172.x.x.x).  It can serve addresses for both lookup zones, and there is no problem with having a DNS server on another subnet.  DNS traffic is pretty minimal, and its definately better than the potential headaches that can arise with dual-NIC comptuers.

The 2 computers that are losing internet connectivity could be doing so for multiple reasons having nothing to do with routes.  Usually if a computer consistently loses its connection after working properly, its either spyware, hardware, or corruption.  I would check spyware/viruses first.

Well that's the 75 point version of my opinion.  Just kiddng =).
greenwarAuthor Commented:
Excellent answer, but before accepting the answer, I'll give ya a little more detail and see if you can provide any other thoughts. Basically, I do have the 10.10.10.x network masked at, so I have that as suggested. I have all of the 10.10.10.x servers set with a gateway of (I selected this randomly and mostly because this was my first server on that ring). What about this gateway, is that an acceptable solution ? As for the ROUTE command and the connectivity issues, YES, I did mean the route which was pointing to the 10.10.10.x network. As soon as I reassigned it to point instead to the 172 network, internet connectivity was like lightening, but as I said after a reboot, was again pointing to the 10.10.10.x network. Both of these servers run the very latest version of Symantec Antivirus (and definitions) along with Microsoft's Beta Spyware tool. They are fully scanned on a daily basis. Any other promising thoughts and you can certainly have the 75 points .... :-)

okay.  you need to remove the default gateway from the tcp/ip configuration on the 10.x.x.x interfaces.  Like I said, computers should have only 1 gateway.  The default gateway is a computer that is on your network that also has access to other networks.

Basically, your computer will know to use the 172.16.x.x interface for the 172.16.x.x network.  It will also know to use the 10.10.10.x interface for the 10.10.10.x network.  But what about an internet address of say google?

Where do you want that to go?  So you configure your computer with a single default gateway which is like a catch-all.  For all communications destined for networks that are not specifically know and don't have static routes, the computer will pass all that traffic to the default gateway.

Having multiple default gateways on a computer confuses it and slows it down.  Sometimes it even prevents good communications.  One one NIC should be configured with the gateway, and the others should be blank

If you don't want internet traffic being routed through your 10.10.10.x network, then disable the default gateway on it by leaving it blank in TCP/IP settings.

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