3com WXR100 3CRWXR10095A User Manual

When a distributed MAP boots on the network, it uses the process 
described in this section. Note that this process applies only to distributed 
MAPs; it does not apply to a directly connected MAP. The boot process 
for a directly connected MAP occurs strictly between the MAP and WX 
switch and makes no use of the network’s DHCP or DNS services.

The boot process for a distributed MAP consists of the following steps:

1 Establishing connectivity on the network

2 Contacting a WX switch

3 Loading and activating an operational image

4 Obtaining configuration information from the WX switch

These steps are described in more detail in the following sections.

When a MAP is first powered on, its bootloader obtains an IP address for 
the MAP. The IP address is either obtained through DHCP (the default) or 
can be statically configured on the MAP.

By default, a distributed MAP obtains its IP address through DHCP. The 
MAP brings up the link on the MAP’s port 1 and attempts the boot 
process outlined below.

1 The MAP sends a DHCP Discover message from the MAP’s port 1 to the 

broadcast address.

2 If a DHCP server is present on the subnet or through a router configured 

to relay DHCP, the server replies with a unicast DHCP Offer message. The 
Offer message must contain the following parameters:

„

IP address for the MAP

„

Domain name of the network

„

IP address of the network’s DNS server

„

IP address of the subnet’s default gateway router (gateway)

Optionally, the DHCP Offer message can also contain a list of WX IP 
addresses or fully qualified hostnames, in the Option 43 field.

3 The MAP broadcasts a DHCP Request to the DHCP servers, and receives an 

Ack from a DHCP server. The MAP then configures its network connection 
with the information contained in the Ack message from that server.