Appendix a. load balancing use cases, Perceived port load, When to use – Dell Emulex Family of Adapters User Manual

Page 807: When not to use, Destination mac, Perceived port load destination mac

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OneCommand NIC Teaming and VLAN Manager User Manual

P009415-01A Rev. A

Appendix A. Load Balancing Use Cases

Perceived Port Load

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Appendix A. Load Balancing Use Cases

Perceived Port Load

This method automatically distributes TCP/IP traffic across team member channels by

examining traffic load history patterns.

When to Use

Favorable types of traffic patterns for this balancing method include web traffic (HTTP,

HTTPS) and e-mail traffic (SMTP, POP3). New TCP/IP connections are assigned to the

more lightly loaded member channel links to balance traffic loading across all members

over time. Only TCP/IP traffic is balanced and distributed (other non-connection

oriented traffic, such as UDP/IP), and non-IP traffic (such as IPX/SPX and others) is

assigned to a single default team member and is not balanced. Once a connection is

opened and assigned to a member link, that TCP/IP connection's traffic is never moved

to a new link without regard to the out-of-balance level the overall team might be

experiencing. There must be a consistent stream of new TCP/IP connections (and

typically a consistent stream of terminated TCP/IP connections which have finished

work) for this traffic balancing method to perform well. This type of process works well

for servers that process a lot of small transactional operations that start and then end

individual TCP/IP connections for each transaction. Some database protocols involve

new connections for each query and these also work well with this method.

When Not to Use

Connections that are very long lived or which are not TCP/IP based are a poor fit with

this choice of balancing technique. Examples of long-lived connections are most

TCP/IP storage traffic such as NFS (Unix/Linux, others), CIFS (Windows), and iSCSI

(widespread usage).

Destination MAC

This method is team member channel selection (hashing) based on the destination

MAC address.

When to Use

Use this method when the local system is the server and the server communicates

through a NIC team to a switch, and then to many other systems on the local subnet

(typically many client, laptop or desktop systems). To be effective, the remote systems

must be located on the same IP address subnet as the server team is located. Use this

method only when the server system communicates with many clients (or other

servers) on the local subnet. Only systems that are on the local subnet have highly

variant destination MAC addresses in Ethernet frames sent from the server system NIC

team to those systems.

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