@jimp:
How did you "recreate" log logs?
They are supposed to have lots of null characters, they are binary circular log files, the are not plain text logs.
They are read with the clog command, such as "clog /var/log/system.log"
Usually that clog crash means that the logs were not created with a clog format.
Use the "clear log" button on a log tab to clean and re-create the log file properly.
Click Save on the Log Settings tab to restart the syslog process which usually will get logs going again.
Thanks very much. I'd actually worked this out at stupid o clock this morning - i.e. that i was being an idiot and assuming the logs were plain text, not binary. On the upside, I now know about clog and a lot more about pfsense, so 10 hours of banging my head against a brick wall wasn't entirely wasted!
Thanks again - the key point to other users if they are stupid like me, is to not manually kill and recreate the log file to clear it! Use the pfsense gui and manually check it's logging using 'clog [filename]' rather than vi.