Using a server as a router - One Ethernet Card?

qsub

Just curious, is there any possible way to make a server a router with only ONE ethernet card?

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Comments

kalebksp

Depends on your definition of routing, I suppose you could have the packet routed directly back to where it came from.

Otherwise, no.

qsub

Well the issue is...

Four computers,

1. Server2k3 /w AD, DNS, DHCP (Static IP - Subnet #1)
2. Server 2k3 /w DHCP Relay, WINS (Static IP - Subnet #2)
3. XP Client (Dynamic IP - Subnet #1)
4. XP Client (Dynamic IP - Subnet #2)

Connectivity Device? Well it's a 8 port switch. This is for a schoo lab, normally our teachers don't like us messing around with the nics so they tell us to not touch them. I really can't get this working exactly at all since when a computer is booted, and it wants an IP address, it broadacsts through the switch and sends it to the main DHCP, not the relay.

edit: fixed subnet error.

kalebksp

I'm not quite understanding what you're trying to do, and I may not be the right person to ask, I'm just starting to study for 290. I can tell you that when the computer broadcasts looking for a DHCP it's obviously not sending it to any particular server, it gets the address of the first one to respond I believe.

TeKniques

Hmmm, I'm not completely sure, but I do not think this is possible. To my understanding a router routes data from one source to a destination. So based on that you would need one input to receive the incoming data from the source and another to transfer the data to the destination. I definitely don't see how a one NIC could work for sending/receiving data between subnets.

Gogousa

There is something I don't understand. Why do you have the DHCP Relay on subnet #1, shouldn't be in subnet #2.
A relay on subnet # 2 would intercept the broadcasts for DHCP from the clients on this subnet and forward them to the DCHP server on subnet #1.
Is this what you are trying to do?

qsub

Gogousa wrote:

There is something I don't understand. Why do you have the DHCP Relay on subnet #1, shouldn't be in subnet #2.
A relay on subnet # 2 would intercept the broadcasts for DHCP from the clients on this subnet and forward them to the DCHP server on subnet #1.
Is this what you are trying to do?

Yeah, typo. Just copied/pasted.

kalebksp

If the clients are configured to get a addresses dynamically then there is no way to insure what subnet the client will be on. If they're configured to be static, then the DHCP servers would be pointless.

kalebksp

My advice would be to find yourself a router and another hub or switch. Using two switches and a router you should be able to achieve two subnets that can communicate with each other.

gabrielbtoledo

One router and one switch with VLANs should do the job.