A friend of mine suggests that all linecards should have the same DFC (3C, 3CXL, 3B etc...), else the port channel might not work properly. In our case, all of the linecards are DFC3B & no service modules will be used so I believe it should be ok.
Thanks, -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Ivan Sent: Tuesday, August 10, 2010 3:02 AM To: [email protected] Subject: Re: [c-nsp] Bundling ports on different WS6704 linecards On 9/Aug/2010 11:22 p.m., Phil Mayers wrote: > On 09/08/10 08:47, Rin wrote: >> Hi group, >> >> >> >> We are building a Core network of 3 7609 routers connecting as a 40Gbps >> ring. On each router we have 4 WS6704 linecards. Each router will be >> connected to other routers via 4 10G-links, these links will be >> configured >> as Port-Channel. >> >> >> >> Should we place each link of the port-channel on different linecard on >> each >> router or should we allocate all 4 links on the same linecard? Anyone has >> any problem with configuring etherchannel for ports on different WS6704 >> linecards? > > We do that extensively. It works fine. It is better to have > cross-linecard portchannels in general. > > HOWEVER - there are a couple of caveats to be aware of. One is if you've > got different linecards with different QoS queuing, you will need: > > int PoX > no mls qos channel-consistency > > Second is that there are some issues with cross-linecard portchannels if > you have service modules (ACE, FWSM, WiSM) in the chassis. I can't > remember the details or find the link at the moment. > _______________________________________________ > cisco-nsp mailing list [email protected] > https://puck.nether.net/mailman/listinfo/cisco-nsp > archive at http://puck.nether.net/pipermail/cisco-nsp/ I was bitten by the FWSM and DEC. The link that was referred to is probably http://www.cisco.com/en/US/ts/fn/610/fn61935.html Field Notice: FN - 61935 - Catalyst 6500 Series and 7600 Series Service Module Incompatibility With Distributed EtherChannel and Packet Re-Circulation "Problem Description When the listed service modules transmit packets to VLANs also used with Distributed EtherChannel (DEC), those packets may be dropped and lost. Background The listed service modules do not support packet re-circulation. Packet re-circulation is a specific means to forward packets internal to the chassis between modules. When the service module attempts to forward a packet onto such a VLAN with packet-recirculation enabled, it may fail and the packet might be lost. When packet re-circulation is not enabled on the destination VLAN, even if DEC is present, this problem will not be encountered." We ended up getting rid of the DEC and using plain EC and "no monitor session servicemodule" as the span sessions were required for other purposes. (http://www.cisco.com/en/US/products/hw/modules/ps2706/products_qanda_item09 186a00801e9e26.shtml#q44) Cheers Ivan _______________________________________________ cisco-nsp mailing list [email protected] https://puck.nether.net/mailman/listinfo/cisco-nsp archive at http://puck.nether.net/pipermail/cisco-nsp/ _______________________________________________ cisco-nsp mailing list [email protected] https://puck.nether.net/mailman/listinfo/cisco-nsp archive at http://puck.nether.net/pipermail/cisco-nsp/
