Ether channel Load balancing best option

[MetCisco_gatz]

Hello 

Dear: Good evening, hello everyone, I hope you are very well. I comment, I have a big doubt about this scenario, a client PC, with two servers, which would be the best load balancing algorithm, for the etherchannel? Thank you very much, greetings and attentive to your comments.

[paul driver]

Hello
Given your topology the PC looks like it going between the two switches which is only giving resiliency and aggregation to the switches

If you wish for the servers to be aggregated then the server requires at least 2 network connections into the switch and then depending on the teaming software the server will use will have a bearing what the switches Port Channel configuration will be attaching to the servers.

You can use 2 types of PC ( Layer 2 or Layer 3 ) with 3 different variations of configuration two of which have link/port negotiation protocols that negotiate a PC via exchanging packets to learn the capabilities of the interfaces in the PC.

• Unconditional -  No link/port negotiation, 
• lacp  - Multi vendor applicable - (recommended)
• pagp  - Cisco proprietary 

Nowadays for switch to server aggregation its seems to be a L2 port channel with LACP unless you’re in a data centre environment then it can be different due to the physical topology and hardware restrictions such a nx-os switches/ fabric extenders etc..)

Lastly you can also change how the traffic is load balanced across the PC by stating the load balance method to be used. For example If these servers are to be receiving traffic from many different source address over many subnets then a scr-dest-ip would be an applicable LB method as each scr-dst-ip flow should then be distributed and LB across the links in PC at a even ratio , However if it’s all local switched traffic than scr-dst-mac could be applicable, S o It can depend on what the server is being used for and the traffic patterns you expect to it to service to get an optimal LB

The only caveat to the LB method is that it’s a global feature on the switch so whatever method is chosen then its applicable to ALL PC’s on the switch and not just specific to a particular one.

 
L2 PC supporting LACP (default LB method)

conf t
default int range x/x –x
int range x/x –x
shut
channel-group 1 mode active

int port 1
description Server Port-Channel
swithport
switchport mode access
switch access vlan 10

int range x/x –x
no shut

sh etherchannel-summary
sh etherchannel port-channel

[MetCisco_gatz]

Hello Paul Driver, very good evening, thank you very much for your answer,

I comment: The topology is as it is in the image. Two servers connected, individually, connected to the switch, which is configured with Etherchannel with 4 physical links to a second switch, exactly as it is in the image (configured with Lacp Active-Passive). My big question, is to know, in this topology and configuration, which is the best load balancing algorithm, assuming that there is a single PC (Client, a single PC), and as a destination two servers, with their own connection and StandAlone configuration. In summary what would be the best and most optimal method of load balancing. dst-mac? src-mac?

Thank you, greetings and very attentive to your comments.

[paul driver]

Hello

In your case I would say yes or  scr-dst-mac would be applicable also which should give you a 2:2:2:2 hash value on the PC interconnects between the two switches

[MetCisco_gatz]

Paul:

Good morning, first of all, excuse the insistence, and thank you for your patience. I still have the doubt, which is the most accurate algorithm, considering only one client PC, 2 switches in portchannel LACP, and two servers stand-alone, for the client PC (as the image), which would be exactly, the most accurate and optimal algorithm to use.

Thank you very much, greetings and very attentive to your comments.

[paul driver]

Hello

Are  you saying you would have no other traffic on these two switchs other than one client and two servers?  - 

are these servers in a different subnet to the client or the same?

[MetCisco_gatz]

Dear Paul:

Good morning, indeed, just a "broadcast-domain", just a subnet.

Only one client PC and two destination servers.

Could you please clarify two scenarios, which is the best load balancing algorithm.

-First scenario (the current and initially raised) .- 1 PC, against the connected switch, in etherchannel LACP, and two servers standalone.

-Second scenario: 10 PCs, against the switch, connected in LACP etherchannel, and two standalone servers.

Thank you for your time and your patience.
Thank you very much and be attentive to your comments