How are you testing the performance? Copying a file from one machine to another is probably not going to use both members of a LAG as it is a single connection on the same tcp/udp port, how the LAG works is that it separates traffic based on the port, so if a copy operation is on one port it is using a single nic and if a second network request is sent for a webpage on a different port it would go out the other nic, but if there are two copy operations on a single port they both will use one nic. You can change this by changing the xmit_hash_policy in linux to change how the computer separates the traffic. https://access.redhat.com/knowledge/docs/en-US/Red_Hat_Enterprise_Linux/6/html/Deployment_Guide/sec-Using_Channel_Bonding.html

The default method in CentOS/RHEL6 is by MAC address, so connections to a single other system for a file copy are not going to split across both nics. You can try to use layer3/4 information for unfragmented packets and it will transmit per packet, but if the packets are fragmented it will use the default method. The 3rd option is to use MAC and ip addresses, but won’t separate on a single copy operation.

The method that the switch uses and the computer uses do not have to match. You are using hashing mode 1 which is probably the best option for you to see improved performance in copy operations as it will transmit per packet on unfragmented packets. However the switch is going to split based on port and ip address and not per packet and there is not a hashing method on these switches that will.

As for the nics not connecting sometimes, what does it show is the link showing down on the switch and on the server?

Hello,

Thanks for information.  But my first task is bring up the LACP/LAG between switch and server.  Did any further advise?  

Thanks!

Machi

To configure the LAG on the switch you select the ports and add them to a channel-group ftp://ftp.dell.com/Manuals/all-products/esuprt_ser_stor_net/esuprt_powerconnect/powerconnect-8100_User%27s%20Guide_en-us.pdf

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Hello,

Yes, I also following those config with example but no luck. 

- Additional it also fail when I tried disable either one of  NIC from my host machine.

- or change the LAG config to port access mode also fail.

Port Channel summary like following for reference.

console#show interfaces port-channel 5

Channel   Ports                         Ch-Type  Hash Type Min-links Local Prf
-------   ----------------------------- -------- --------- --------- ---------
Po5       Active: Te2/0/5, Te1/0/5      Static   3         1         Disabled

console#show interfaces port-channel 7

Channel   Ports                         Ch-Type  Hash Type Min-links Local Prf
-------   ----------------------------- -------- --------- --------- ---------
Po7       Active: Te1/0/7, Te2/0/7      Static   1         1         Disabled

Thanks for further advise

Try creating a static LAG instead of LACP and see if that works better. It is possible that something with the LACP packets is the problem.

Hello,

Unfortunately already setup as a LAG from the first day.  It can see by port-channel status shown "static" there.

If it is a static LAG than it doesn’t need LACP packets to work and is going to be always on and the issue is not on the switch side.

Hello,

So, the problem may be from HOST side?  Any others reference? or easy to debug the problem?

Thanks!

If the switch is set to a static LAG it treats the ports as part of a LAG regardless of whether there are LACP packets showing up, so if that is not working, the issue is not with the configuration on the switch, it could be a bad port, but a cable or host issue is more likely. Do the ports work individually without a LAG?