Turn off mac leaning UCS

[mikekulls]

We have a single fabric interconnect with 7 servers connected to it. I am receiving traffic which I wish to capture on a single server but the destination macs are not for this server. Because of that the packets are getting discarded by the fabric interconnect. This traffic is on vlan 4090. Is there some way to send all traffic for vlan 4090 through to one particular server? Setting up a new vnic that would receive all this traffic would be ideal.

If that doesn't make sense, here's the longer description of what I am trying to do. I have a feed of traffic that is a mirror of radius and dhcp traffic from our radius and DHCP servers. We wish to capture all of this traffic on one server and store it in a file. We have the feed working and can see traffic on a non UCS server by setting the network card to promiscuous mode and turning off mac learning on a non-UCS switch we are using. However, in the UCS environment those packets are not getting through. In short, can I turn off mac learning (or whatever the FI does) just for vlan 4090 and flood those packets to any server that has a vnic on 4090?

[Charles Stizza · Accepted solution]

Hi Mike,

This makes perfect sense.  You basically want to SPAN all traffic and use the vNIC interface as a destination.  See CSCtr80980.

This feature is not currently supported.

What you could do is send a unidirectional ERSPAN session to the UCS VM if your source allows this.  What are the source servers connected to? Nexus switch?   (Wireshark can decapsulate this and save it to a rolling capture file.)

Charles

[mikekulls]

Thanks Charles. That sounds like the perfect solution but unfortunately we have Catalyst switches which I have been told don't support this feature. Details are below. I have been approved to purchase a new switch but that could take a while :-) We are probably going to run a 1G copper cable straight to one of the server in the interim.

Cisco IOS Software, C3750 Software (C3750-IPSERVICESK9-M), Version 12.2(55)SE10, RELEASE SOFTWARE (fc2)
Technical Support: http://www.cisco.com/techsupport
Copyright (coffee) 1986-2015 by Cisco Systems, Inc.
Compiled Wed 11-Feb-15 11:40 by prod_rel_team
Image text-base: 0x01000000, data-base: 0x02F00000

ROM: Bootstrap program is C3750 boot loader
BOOTLDR: C3750 Boot Loader (C3750-HBOOT-M) Version 12.2(44)SE5, RELEASE SOFTWARE (fc1)

tasmdlcaty uptime is 1 week, 10 minutes
System returned to ROM by power-on
System restarted at 13:39:04 EST Thu Aug 20 2015
System image file is "flash:c3750-ipservicesk9-mz.122-55.SE10.bin"

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WS-C3750G-24TS-1U

catalyst sw

c3750-ipservicesk9-mz.122-55.SE10.bin