Thanks for all of you who responded with info about etherchannel information. The core appears to be algorithm used for packet distribution among interfaces (which I can't change on 5500): "The EBC performs an X-OR operation on the last two bits of the source MAC address and the destination MAC address. This operation yields one of four results: (0 0), (0 1), (1 0), or (1 1). Each of these values points to a link in the Fast EtherChannel bundle" Apparently I have bad combination of source mac addresses (I only have 7 main servers responsible for most traffic and only one destination) and solution in this case appears to be to manually change MAC addresses of some servers until I can acheive better load-balancing. On Wed, 20 Oct 2004, william(at)elan.net wrote:
Hi,
I have etherchannel setup between cisco 7500 router and 5500 switch.
For data going from 7500 router everything seems to be ok and data is well split between four interfaces with about 1/4th sent to each one (about 40% utilization each right now).
But for data going from 5500 switch the split appears to be that one interface has 100% utilization while another one is 20% and others are less then 10%. So its not really splitting data on random basis to each interface and uses other interfaces as overflow after the main one. I don't like this as the one interface that is 100% full appears to sometimes be dropping packets on either switch or cisco router side.
I'm wondering what I can do to force 5500 to use etherchannel in similar way cisco 7500 does?
-- William Leibzon Elan Networks william@elan.net