3750 stack

[V98Cubes]

I have a new stack of 3750's. The lowest mac seems to be the master with interfaces starting at 1/0/1 - 48 and 2/0/1 - 48. My question is if I loose a switch does the port allications remain the same.

Thanks
V

 

[leedsit]

It does. if switch 1 died, switch 2 will still be switch 2 thus 2/0/1 - 48 remains that.

Check out this document, its short but informative...

http://www.cisco.com/en/US/products...s_configuration_example09186a00807811ad.shtml

LEEroy
MCNE6,CCNP,CWNA,CCSA,Project+

 

[V98Cubes]

one more question? While doing a port-channel config is there a way to tell that the data running accross the channel is balanced?

 

[leedsit]

Im not sure that it is entirely load balanced. For example this is the stats off our bundled 10GB links....

Port InOctets InUcastPkts InMcastPkts InBcastPkts
Po1 59536611271 232617676 22375879 335063
Te1/0/1 42435661042 161912255 13724560 316630
Te2/0/1 17100950229 70705421 8651319 18433

Port OutOctets OutUcastPkts OutMcastPkts OutBcastPkts
Po1 392976306901 411095648 710758 629068
Te1/0/1 99225327693 164087169 499996 279971
Te2/0/1 293750979208 247008479 210762 349097

and you can see they are not packet/packet load balanced... I beleive it makes a decision on what link to use based on a hash i.e

#show etherchannel load-balance
EtherChannel Load-Balancing Configuration:
src-mac

EtherChannel Load-Balancing Addresses Used Per-Protocol:
Non-IP: Source MAC address
IPv4: Source MAC address
IPv6: Source MAC address

Ive never dealved in the bundles too deeply.. maybe someone else can shed some more light...




LEEroy
MCNE6,CCNP,CWNA,CCSA,Project+

 

[unclerico]

leedsit is correct, the data will not be load balanced equally. the xor algorithm will determine which link in the bundle is used depending on the load-balancing scheme selected and number of links in the bundle.

I hate all Uppercase... I don't want my groups to seem angry at me all the time! =)
- ColdFlame (vbscript forum)

 

[Cluebird]

If most of the traffic is IP, you may want to do the load balancing with source-destination IP. That way each flow uses a different link:

Switch(config)#port-channel load-balance src-dst-ip

HTH

 

[VinceWhirlwind]

According to the doco I am reading, these are your options:

port-channel load-balance...
src-mac
dst-mac
src-dst-mac
src-ip
dst-ip
src-dst-ip
src-port
dst-port
src-dst-port