Dell Power Connect 2816 and Aggregation

[Hello man]

Hey!

I am not a networking genius-I build computers, not network infrastructures most of the time. However, I recently bought two quad port gigabit NICs and the aforementioned switch (PowerConnect 2816). What I need to do is create two 4 Gigabit aggregate links between two towers (personal rig, storage server) as well as have them visible to the rest of the network.

Here is what happens when I try:

I have ports 2468 configured as LAG1 and 10121416 as LAG2 on the switch. A network cable connected to the rest of the network is in port 15 for DHCP, which I have set to pass through from the rest of the network. Nothing here sounds wrong to me.

The issue is in Windows-some of the ports on the NIC are not assigned IP addresses it seems. Say I have 3 Ethernet cables plugged in. Ports 1 and 2 might have an IP address, but 3 doesn't and says "unidentified network" unlike the other two. So naturally, when I try to bridge them, the whole thing becomes an "unidentified network".

Here's another thing I noticed-my WIFI became un-joinable when I had both computers and all the network cables plugged in. Could I be running out of IP addresses? I have quite a few devices on the network, and if each port requires an independent address maybe that is the issue? I don't think I have more than 50 devices though. My address table goes from .1 to .200, so I dont understand the problem.

Thanks,

Rowan

 

[bill001g]

Sounds like you have the pc setup wrong. The ports on the PC will not get ip addresses there should be a different interface that represents the LAG group of ports combined. You will only have a single ip on the pc.

If you have the switch setup for port aggregation and not the PC you can easily get network loops and take your whole network down with a broadcast storm.

You are likely wasting your time though. The most common form of LAG is the standard 802.3ad. Using this the path selection for the data is done with a hash. It will only use a single port...ie 1gbit in your case...between the 2 machines for a single data transfer. So for simple file copies it is not better than a single cable. Even if you run multiple parallel file sessions it may or may not use multiple. It is mathematical selection so it can attempt to put both on the same connection and leave the others unused. It works best in a sever situation where many hundreds of machines are talking with a central server. The random in the ip/ports will make the math load balance the sessions a little better.

There are some proprietary LAG implementations that can use multiple but like any thing proprietary all the equipment must support it. Generally it is only used for example to connect between a end device and disk array most switches only support the standard 802.3ad.

Almost all commercial installation stopped using port aggregation because of this issue and have gone to 10gbit since the price came down.