3Com WXR100 3CRWXR10095A, WX4400 3CRWX440095A manual Resiliency and Dual-Homing Options for MAPs

184CHAPTER 10: CONFIGURING MAP ACCESS POINTS

Resiliency and Dual-Homing Options for MAPs

MAPs can support a wide variety of resiliency options. Redundancy for data link connections and for WX services can be provided to the MAP.

„PoE redundancy—On MAP models that have two Ethernet ports, you can provide PoE redundancy by connecting both ports to PoE sources. PoE can come from a directly connected WX or a PoE injector.

Dual-homing support for PoE is automatically enabled when you connect both MAP Ethernet ports.

„Data link redundancy—You can provide data link redundancy by connecting both Ethernet ports directly to one WX, two WX switches, an intermediate Ethernet switch, or a combination of WX and Ethernet switch. If an intermediate Ethernet connection is used, you also need a Distributed MAP configuration on a WX somewhere in the network. Dual-homing support for data link redundancy is automatically enabled when you connect both MAP Ethernet ports.

„WX redundancy—You can provide redundancy of WX services by dual-homing the MAP to two directly connected WX switches; or by configuring a Distributed MAP configuration either on two or more indirectly connected WX switches, or on a combination of a directly connected WX and one or more indirectly connected WX switches. To provide WX redundancy on a MAP model that has only one MAP port, configure a Distributed MAP connection on two or more indirectly connected WX switches.

Bias On a WX, configurations for MAPs have a bias (low or high) associated with them. The default is high. A WX with high bias for a MAP is preferred over a WX with low bias for the MAP

If more than one WX has high bias, or the bias for all connections is the same, the WX with the greatest capacity to add more active MAPs is preferred. For example, if one WX has 50 active MAPs while another WX has 60 active MAPs, and both WX switches are capable of managing 80 active MAPs, the new MAP uses the WX that has only 50 active MAPs.

Bias applies only to WX switches that are indirectly attached to the MAP through an intermediate Layer 2 or Layer 3 network. A MAP always attempts to boot on MAP port 1 first, and if a WX switch is directly attached on MAP port 1, the MAP boots from it regardless of the bias settings.

(To set the bias for a MAP configuration, see “Changing Bias” on page 227.)