Hi. > We have (2) Metro Ethernet connections from two different carriers > connecting our two locations at the moment. We need to provide for > redundancy at the L2 level for these, and would like to combine the > bandwidth into one logical bundle. > > We will be using Cisco switches on both sides of the link(s), and it seems > 802.3ad is the way to go -- but I'm not sure if LACP or EtherChannel is > appropriate here, or if there is something else I should be considering.
EtherChannel can be used if, and only if, both carriers tunnels the EtherChannel protocol. Such tunneling is only supported on VPWS (aka Q-in-Q) type of circuits. For some additional info, for example look at: http://www.cisco.com/en/US/docs/switches/metro/me3400e/software/release/12.2_52_se/configuration/guide/swtunnel.html#wp1005050 > Also, to throw another issue into the mix -- these two links are not > currently equally sized -- one is shaped to 600M, the other is a full Gig, > so a way to specify link speed and have it load balanced appropriately would > be great as well. This can't be fixed with EtherChannels. If you instead use IP, GLBP (http://www.cisco.com/en/US/docs/ios/ipapp/configuration/guide/ipapp_glbp_ps10591_TSD_Products_Configuration_Guide_Chapter.html) might solve that (provided you have a decent src/dst distribution). The old truth "Good, fast, cheap -- pick two, you can't get all three" still holds, and with L2-switching you are stuck with "fast" and "cheap"... -- Pelle _______________________________________________ cisco-nsp mailing list [email protected] https://puck.nether.net/mailman/listinfo/cisco-nsp archive at http://puck.nether.net/pipermail/cisco-nsp/
