Crashing Extreme WM-200

We've had a couple of instances where an Extreme WM-200 wireless controller will lockup and become unresponsive (though still functional, we can't log on to it), and in each instance we've found it's due to the internal hard disk filling up with log messages (specifically the /var/log/messages file, which should rotate but doesn't). This is pretty easy to fix, but finding out a) the cause and b) how to fix it can be very fiddly, so hopefully this can save someone a frustrating evening.

You'll need to console onto the failed unit and reboot it. We need to get it into single user mode, so when the GRUB screen comes up arrest it by pressing a key, then hit 'e' to edit the GRUB loader. Press 1, to select line 1, then 'e' again to edit it, and add 1 to the end of the line. Then press Enter and hit b to boot the edited loader. This should go through a basic boot cycle, dropping you into a bash shell with just a hash.

From here you can verify if it is indeed a full disk that's causing the trouble, just type df and see if any of the mounts are 100% used.

So far so good, now we need to remount the filesystems so we can clear some space. After much digging in the /etc directory, the following lines should build a usable filesystem for you:

 mount -n -t proc none /proc
 mount -a -t nonfs
 mount -o defaults,noatime,nodiratime /dev/ide/host0/bus1/target0/lun0/part1 /mnt/flash &> /dev/null
 mount -o defaults,noatime,nodiratime /dev/ide/host0/bus0/target0/lun0/part2 /original_root/
 mount -o defaults,noatime,nodiratime /dev/ide/host0/bus0/target0/lun0/part5 /original_root/var/controller/images
 mount -o defaults,noatime,nodiratime /dev/ide/host0/bus0/target0/lun0/part7 /original_root/var/controller/log
 mount -o defaults,noatime,nodiratime /dev/ide/host0/bus0/target0/lun0/part6 /original_root/var/controller/log/cdr

From here it's just a simple matter of browsing to the /var/log directory and issuing:

 rm -f messages

Type reboot, and you should be good to go.