I'm trying to bond two interfaces together on my filer, to create a 2Gb link. They connect to a Cisco 3750. On the Cisco side I setup a port channel, and added the two physical ports to it. On the NetApp side I added those two interfaces to a vif. On the Cisco side both ports show up and active, and traffic is flowing just fine.
But I'm noticing that I often spike 1 physical interface to nearly 100% (960Mbs), and the other interface never shows any traffic. It seems like I'm peaking at 1Gbs, and the second link is never being used.
Is there anything I should look at to confirm my port channel is setup correctly for load balancing? Here's my Cisco config:
Thanks phitchcock. But I checked my /etc/rc file and it looks correct. Both my switch and netapp should be using LACP:
#Regenerated by registry Wed May 12 10:09:04 EDT 2010 #Auto-generated by setup Tue May 11 05:57:26 GMT 2010 hostname nas vif create lacp vif01 -b port e0a e0b vif create lacp vif02 -b port e0c e0d
From Cisco switch
show etherchannel 1 port-channel Port-channels in the group: ---------------------------
Port-channel: Po1 (Primary Aggregator)
Age of the Port-channel = 55d:11h:58m:20s Logical slot/port = 10/1 Number of ports = 2 HotStandBy port = null Port state = Port-channel Ag-Inuse Protocol = LACP
Ports in the Port-channel:
Index Load Port EC state No of bits ------+------+------+------------------+----------- 0 00 Gi1/0/2 Active 0 0 00 Gi1/0/3 Active 0
I was also reading this blog http://blog.scottlowe.org/2008/01/08/lacp-with-cisco-switches-and-netapp-vifs/ which seems to indicate I have things setup correctly. But down on the comments someone mentions "port-channel load-balance src-dst-mac". Another article mentions using "port-channel load-balance src-dst-ip". I don't have either defined. Maybe that's the problem. But not sure of which to use, and the impact.
Adding port-channel load-balance src-dst-ip did indeed help -- as it was previously load balancing the destination, which was a single IP. Now balancing the source spreads the load of our source hosts evenly.
But it's also true that if a single host is causing the spike, it will use a single link.