multicast over etherchannel

[phillipediab]

does etherchannel cause multicast packets to be received out of sequence, gapping, duplicate..etc ??? in general, would etherchannel affect multicast traffic ?

[nambi_gct]

etherchannel should NOT affect multicast.From software perspective it is just an interface, though there are many physical interfaces.Whether unicast or multicast, ether channel load sharing happens in the same way.There is no possibility of duplicate introduced by etherchannel.

[phillipediab]

thanks -

[Edison Ortiz]

The traffic will be treated the same as unicast. No out of sequence, gaping or duplicate should be seen. The hashing algorithm when distributing the load will prevent that.

You can change the load balancing on the etherchanneling depending upon your switch.

Load balancing can be:

port-channel load-balance {dst-ip | dst-mac | src-dst-ip | src-dst-mac | src-ip | src-mac}

http://www.cisco.com/en/US/docs/switches/lan/catalyst3560/software/release/12.2_25_see/configuration/guide/swethchl.html#wp1276203

[phillipediab]

Thanks -

[Sociable Wilson]

May i ask what hashing algorithm are you talking about? Thanks.

[ramixpe81]

i thought the multicast will go only through the default port !!

[Peter Paluch]

Hello,

The default port was a concept used, to my best knowledge, only on 2900XL/3500XL/2950/2955/3550 Catalyst switches. Newer switches do not implement the concept of a default port in an EtherChannel bundle, and instead, load-balance all traffic using the same hashing mechanism.

See the following document for more information (search for the "default port" in the document contents):

http://www.cisco.com/en/US/tech/tk389/tk213/technologies_tech_note09186a0080094714.shtml

Best regards,

Peter

[ramixpe81]

helpfull thank you