Etherchannel on 6506

[ErrolDC]

I'm trying to understand the way etherchannel balances traffic between NICs that are channeled. I have a server with an Intel 10/100/1000 Dual Port NIC. I've created a channel between it and our 6506. I've been watching and it seems as if its being balanced in such a way that one NIC is being dedicated to sending and the other receiving. Here is some relevant data.

Console> (enable) show ch tr
ChanId Port Rx-Ucst Tx-Ucst Rx-Mcst Tx-Mcst Rx-Bcst Tx-Bcst
------ ----- ------- ------- ------- ------- ------- -------
820 6/39 99.61% 0.00% 50.00% 87.50% 57.09% 2.74%
820 6/44 0.39% 100.00% 50.00% 12.50% 42.91% 97.26%
821 6/41 99.74% 1.10% 0.00% 87.50% 9.17% 61.80%
821 6/46 0.26% 98.90% 0.00% 12.50% 90.83% 38.20%
823 6/45 97.32% 2.16% 0.00% 87.49% 64.00% 93.98%
823 6/48 2.68% 97.84% 0.00% 12.51% 36.00% 6.02%

As you can see from Unicast traffic stats, it's not 50/50 or even close as i would want it to be.


Console> (enable) sh port 6/44
Port Name Status Vlan Duplex Speed Type
----- -------------------- ---------- ---------- ------ ----- ------------
6/44 connected 30 full 100 10/100BaseTX

Port AuxiliaryVlan AuxVlan-Status InlinePowered PowerAllocated
Admin Oper Detected mWatt mA @42V
----- ------------- -------------- ----- ------ -------- ----- --------
6/44 none none - - - - -


Port Security Violation Shutdown-Time Age-Time Max-Addr Trap IfIndex
----- -------- --------- ------------- -------- -------- -------- -------
6/44 disabled shutdown 0 0 1 disabled 197

Port Num-Addr Secure-Src-Addr Age-Left Last-Src-Addr Shutdown/Time-Left
----- -------- ----------------- -------- ----------------- ------------------
6/44 0 - - - - -

Port Broadcast-Limit Multicast Unicast Total-Drop
-------- --------------- --------- ------- --------------------
6/44 - - - 0

Port Send FlowControl Receive FlowControl RxPause TxPause
admin oper admin oper
----- -------- -------- --------- --------- ---------- ----------
6/44 off off off on 0 0

Port Status Channel Admin Ch
Mode Group Id
----- ---------- -------------------- ----- -----
6/39 connected on 308 820
6/44 connected on 308 820
----- ---------- -------------------- ----- -----

Port Align-Err FCS-Err Xmit-Err Rcv-Err UnderSize
----- ---------- ---------- ---------- ---------- ---------
6/44 0 0 0 0 0

Port Single-Col Multi-Coll Late-Coll Excess-Col Carri-Sen Runts Giants
----- ---------- ---------- ---------- ---------- --------- --------- ---------
6/44 0 0 0 0 0 0 0

Port Last-Time-Cleared
----- --------------------------
6/44 Fri Aug 6 2004, 23:02:40


Anybody got any thoughts?

 

[juniperr]

EtherChannel load balancing can use MAC addresses, IP addresses, or Layer 4 port numbers with a PFC2 and either source, destination, or both. The selected mode applies to all EtherChannels configured on the switch. Use the option that provides the greatest variety in your configuration. For example, if the traffic on a channel is going only to a single MAC address, using the destination MAC address always chooses the same link in the channel; using source addresses or IP addresses might result in better load balancing. The load balancing can be configured using the 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} global configuration command.

 

[ErrolDC]

I believe I understand your point. My goal of using the channel is to increase throughput on our backups. Since we have a single destination and multiple sources, would I set the load balancing to source on the channel for the backup server and destination for the channels for the other servers?