ios slb…

server load balancing… from: http://www.cisco.com/en/US/docs/ios-xml/ios/slb/configuration/15-s/Information_About_Cisco_IOS_SLB.html#GUID-E26EEC88-5EE0-4F72-9A4C-A05DC7A2EA6B

The SLB feature is a Cisco IOS-based solution that provides IP server load balancing. Using the IOS SLB feature:

  1.  The network administrator defines a virtual server that represents a group of real servers in a cluster of network servers known as a server farm. In this environment the clients are configured to connect to the IP address of the virtual server.
  2.  The virtual server IP address is configured as a loopback address, or secondary IP address, on each of the real servers.
  3.  When a client initiates a connection to the virtual server, the IOS SLB function chooses a real server for the connection based on a configured load-balancing algorithm.

The IOS SLB feature provides load balancing for a variety of networked devices and services, including:

  • Application servers, such as Hypertext Transfer Protocol (HTTP), Telnet, File Transfer Protocol (FTP), and so on
  • Firewalls
  • Service nodes, such as authentication, authorization, and accounting (AAA) servers, web caches, and so on