Capwap Mailing List: Issue: WTP restarts after firmware download

[Bob O'Hara (boohara) (boohara]

I believe that the expected resolution to Issue 200 (Trickle Firmware
Download) is to provide for download of firmware while the WTP is in the
RUN state and servicing wireless clients.  In this case, it may be
expected that the download of firmware to a large group of WTPs will not
conclude simultaneously.  In fact, one operational scenario is to
download new firmware versions to small groups of WTPs, only downloading
to new groups of WTPs after the prior group has completed.  It will be
desirable for the WTPs that have concluded the firmware download to
continue in the RUN state, until a RESET message is received.  This will
allow the orderly restart of the WTPs, so that all come up on the same
(or compatible) firmware version.

There are two problems that this introduces.  First, a WTP may
spontaneously restart, due to removal and reapplication of power or
other reasons outside of the control of the CAPWAP protocol.  Second,
the WTP may need to be restarted under the control of the CAPWAP
protocol, but continue using the earlier version of firmware.

I propose that we add a function to CAPWAP to control the version of
firmware that is used when a WTP restarts.  Some alternatives are the
following.

1. Require the WTP to maintain a nonvolatile "last boot version" that is
used as the source of the version of firmware for the next boot and add
a new configure message element to change this value.

2. Require that the WTP always restart on the last firmware version it
booted from and add a firmware version message element to the Reset
Request message to cause the WTP to restart using a different version.

I am sure there are other ways to accomplish this and welcome other
suggestions.

 -Bob

Bob O'Hara
Cisco Systems - WNBU

Phone:  +1 408 853 5513
Mobile: +1 408 218 4025