Network Warrior

Configuring Server Load Balancing

In this section, I will explain how to configure real servers, server farms, and virtual servers in IOS SLB and CSMs.

IOS SLB

Configuration relating to SLB is done with the ip slb command, or in SLB configuration mode. Real servers and virtual servers must be on different VLANs when using SLB.

Real servers

When using SLB, real servers are not configured independently, but rather, within server farms.

Server farms

Server farms are created in SLB with the ip slb serverfarm farm-name command. Here, I've created a server farm named GAD-FARM. The nat server command is a default and will be inserted by IOS:

ip slb serverfarm GAD-FARM
 nat server

Tip

Don't bother trying to come up with names for your servers in lowercase or a combination of upper- and lowercase. No matter how you enter names when using SLB or CSMs, the parser will convert them to uppercase.

Once in ip slb configuration mode, add the real servers to be included in the server farm with the real ip-address command. Here, I've configured two real servers. The first one is in service, and the second is out of service:

 real 10.10.10.100
  inservice
 !
 real 10.10.10.101
  no inservice

The final configuration for the server farm is as follows:

ip slb serverfarm GAD-FARM
 nat server
 real 10.10.10.100
  inservice
 !
 real 10.10.10.101
  no inservice

Virtual servers

Virtual servers are configured in SLB with the ip slb vserver server-name command. You must configure the IP address for the virtual server, the port or ports ...