3Com WX2200 3CRWX220095A Switch User Manual


 
MAP Overview 191
If no WX switches reply, the MAP repeatedly resends the Find WX
messages. If no WX switches reply, the process continues with step 3.
2 If no IP addresses or hostnames were specified in the Option 43 field of
the DHCP Offer message, the MAP sends a Find WX message to UDP port
5000 on the subnet broadcast address.
WX switches in the same IP subnet as the MAP receive the message
and respond with a Find WX Reply message.
If the MAP is configured as a Distributed MAP on a switch and the
connection bias is high, the WX switch immediately sends a Find
WX Reply message.
If the MAP is configured as a Distributed MAP on a switch but the
connection bias is low, that WX switch waits one second, then
sends a Find WX Reply message. The delay allows switches with
high bias for the MAP to respond first.
If a WX switch that receives the Find WX message does not have
the Distributed MAP in its configuration but another WX switch in
the same Mobility Domain does, the switch waits two seconds,
then sends a Find WX Reply message with the IP address of the
best switch to use. The determination of best switch is based on
the bias settings for the MAP on each switch and on the capacity
of each switch to add new active MAP connections.
The process skips to step 6.
If no WX switches reply, the MAP repeatedly resends the Find WX
broadcast. If still no WX switches reply, the process continues with
step 3.
3 If the MAP is unable to locate a WX on the subnet it is connected to, and
is unable to find a WX based on information in the DHCP option 43 field,
the MAP sends DNS requests for both 3COM and wlan-switch, where the
DNS suffix for mynetwork.com is learned through DHCP.
You must configure a DNS address record on your DNS server for the WX
IP address. Otherwise, the DNS server cannot provide the WX switch’s
address to the MAP.
4 The DNS server replies with the system IP address of a WX switch.
If only 3COM is defined in DNS, the MAP sends a unicast Find WX
message to the WX switch whose IP address is returned for 3Com.