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We have a Poweredge R210 running WS2K8R2. The server has two Broadcom 5716C NICs running Broadcom BASP. I can team the NICs using the 802.3ad protocol on the server end no problem. I have no VLAN.

Now I go to the 2824 switch (default settings all round) running in managed mode and create a LAG with ports g1 and g2. As soon as I add these ports, I lose the ability to send traffic to or from the server.

I am much more of a server guy than a networking guy, what am I doing wrong here?

Server Static IP Address: Network mask: Gateway:

The 2824 switch has an IP address of and in turn has its gateway as our firewall server running ISA Server at

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If the switch's gateway is another IP on the local subnet, it will tell all the other computers that, so they send traffic directly to that IP and cut the middle man out. – Chris S May 28 '10 at 17:02

I don't believe the 2800 series PowerConnects are Layer 3 switches. The only mentioning I can find of Layer 3 in regards to this series is the QoS is Layer 3 aware. That would mean setting your gateway to the switch will make it unable to get out to other networks, as 'Chris S' said skip the middle man, point straight to the ISA for the default gateway.

As for the LACP issue, these switches support 802.3ad in static form only, not auto-negotiated using LACP. This means you have to great the bundle yourself. See the manual on how to do that. I think you'd need to change the Broadcomm configuration to use FEC/GEC generic trunking option instead of LACP. I don't have a box I can test to verify at the moment.

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The Broadcom term for non-LACP NIC Teaming is "Generic Trunking (FEC/GEC)/802.3ad-Draft Static". Choose this and make sure the PVID is set to your native VLAN. Also notice the "ingress filtering" option. You might need to disable this as well.

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If the switches don't support LACP (802.3ad) then you need to do manual trunks at both ends. You can't set one end to automatic (LACP) and the other end to manual (LAGG w/o LACP).

I believe the Broadcom NIC Teaming term for manually configured Trunks is "Switch Assisted Load Balancing"

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I guess this is where I'm getting confused. The Dell Powerconnect 2824 documentation says it supports 802.3ad, is this not LACP? – Carltoncl May 28 '10 at 16:40
802.3ad is LACP, but if you're using it you shouldn't have to create the Trunk on the switches, the NIC should talk to the switches and create the trunk as is appropriate. I'm not very familiar with Powerconnect, perhaps LACP can be turned off, or is off by default. – Chris S May 28 '10 at 17:00

Is that a layer 2 or 3 switch? If it's a layer 2 switch why does it have a DG? If it's a layer 3 switch are you using it as a router as well as a switch? The switch's ip address and DG settings should be irrelevant to creating a LAG port. Why do you have your servers configured to use the switch as their DG? That shouldn't be neccessary. Take a step back and get the switch working as a layer 2 device first, then get your LAG port set up.

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Hmm, great question. Dell's tech specs don't specify it to be layer 2 or 3 but internally the UI leads me to believe it supports L3.… – Carltoncl May 28 '10 at 16:43
If it support static routing rules, it's L3. If there's nothing about routes (other than default gateway) it's probably L2. – Chris S May 28 '10 at 17:02
Chris, I think the statement "if it support static routing rules, it's L3" is incorrect. I've seen switches that allow you to assign routes on them for management purposes only, and it won't do any Layer 3 work for the connected clients. A switch can also have a gateway for the same reason, management access. – Jon Angliss May 28 '10 at 23:09
@Jon: Good point. I can see the need for a layer 2 device to have a DG for things like uploading\downloading firmware, etc. from the internet and for accessing the management interface from another LAN. Thanks. – joeqwerty May 29 '10 at 0:01
The PowerConnect 2824 is a layer 2 switch. Its only layer 3 functionality relates to management. (I use a number of these at Customer sites with small networks and am fairly familiar with them and their predecessor, the 2724.) – Evan Anderson Jul 19 '11 at 20:31

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