3com WXR100 3CRWXR10095A User Manual

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 10: C
ONFIGURING
 MAP A
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 P
OINTS
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.)