Thanks JorgeOliveira for that link – I had seen it, after the fact of course!
When I installed 2.2.6 AMD64 from iso I then brought in my full config backup file. I think it's unlikely I would have 'hard coded' any particular update path into my settings, I probably had it set to just install stable updates.
I think that is a pretty odd situation to end up in ... running any auto-update on a 64 bit system and ending up with a 32 bit system and I think there should have been some means of preventing that or at least warning about it.
In any case, I backed up my config file again, did a clean install of 2.3.1 from the amd64 full install iso, reloaded my config file, and my system is working again.
Sadly, it seems my RRD data was lost. It is working again, creating new data, but I can't go back to see old data. Does anyone know how that works? I was looking in /var/db/rrd/ and my files are not too small, like:
-rw-r--r-- 1 nobody wheel 144K May 30 18:19 WAN_DHCP-quality.rrd
-rw-r--r-- 1 nobody wheel 384K May 30 18:19 ipsec-packets.rrd
-rw-r--r-- 1 nobody wheel 384K May 30 18:19 ipsec-traffic.rrd
-rw-r--r-- 1 nobody wheel 384K May 30 18:19 lan-packets.rrd
-rw-r--r-- 1 nobody wheel 288K May 30 18:19 lan-queuedrops.rrd
-rw-r--r-- 1 nobody wheel 288K May 30 18:19 lan-queues.rrd
-rw-r--r-- 1 nobody wheel 384K May 30 18:19 lan-traffic.rrd
-rw-r--r-- 1 nobody wheel 384K May 30 18:19 ovpns1-packets.rrd
-rw-r--r-- 1 nobody wheel 384K May 30 18:19 ovpns1-traffic.rrd
-rw-r--r-- 1 nobody wheel 49K May 30 18:19 ovpns1-vpnusers.rrd
-rw-r--r-- 1 nobody wheel 575K May 30 18:19 system-mbuf.rrd
-rw-r--r-- 1 nobody wheel 718K May 30 18:19 system-memory.rrd
-rw-r--r-- 1 nobody wheel 240K May 30 18:19 system-processor.rrd
-rw-r--r-- 1 nobody wheel 240K May 30 18:19 system-states.rrd
-rw-r--r-- 1 root wheel 8.7K May 30 18:13 updaterrd.sh
-rw-r--r-- 1 nobody wheel 384K May 30 18:19 wan-packets.rrd
-rw-r--r-- 1 nobody wheel 240K May 30 18:19 wan-queuedrops.rrd
-rw-r--r-- 1 nobody wheel 240K May 30 18:19 wan-queues.rrd
-rw-r--r-- 1 nobody wheel 384K May 30 18:19 wan-traffic.rrd
Is that the size of 'blank' rrd data? Was the data 'poisoned' by running the 32 bit OS briefly? I'm not sure I ever did a backup that contained the full RRD data, my XML backups are usually 150k or so.
Thanks.