To make the log format predictable, create /etc/fw/conf/logexport.ini with the following
For R70 (Secuplat):
[Fields_Info] included_fields=num,date,time,src,dst,proto,service,action,xlatesrc,xlatedst,peer gateway,<REST_OF_FIELDS>
For R77 (GAIA):
[Fields_Info] included_fields=date,time,src,dst,proto,service,action,xlatesrc,xlatedst,peer gateway,<REST_OF_FIELDS>
Create a directory for the converted logs:
mkdir /var/log/2019.txt
Run the following command to convert all logs, for example, for January 2019:
for i in $FWDIR/log/2019-01-*.log; do echo $i; fwm logexport -n -p -i $i | gzip -c - > /var/log/2019.txt/$i.txt.gz; done