Upgrade IOS on 877W ISR Wireless Module

It is a bit tricky to update the AP module inside the Cisco ISR 877 Series.

1st, assign an IP address to the VLAN of the router

interface vlan 1

ip address x.x.x.x y.y.y.y

no shut

2nd, assign the wlan-ap 0 interface with IP unnumbered

interface wlan-ap 0

ip unnumbered vlan 1

3nd, access the wlan-ap 0 module console

service-module wlan-ap 0 session

4th, assign an IP address to BVI0/BVI1 interface

interface BVI0

ip address z.z.z.z y.y.y.y

no shut

5th, get the IOS image from the tftp

archive download-sw tftp://x.x.x.x/ios.version.tar

6th, write mem and reload

wr mem

reload