Upgrade Graylog server from el7 to el8

Install a new server with EL8, using our kickstart file

On the old server, stop graylog and backup its mongo database

systemctl stop graylog-server pre-backup # Copy /home/lbkp/mongo/graylog somewhere

Shutdown the old server and start the new one with the same IP

Ensure log listeners won't be accessible yet (either disable rules on the main firewall, or set graylog_http_src_ip to an empty array)

Run the ansible playbook :

ansible-playbook -i inventories/fws.ini fws.yml -l graylog.fws.fr

Stop Graylog service, copy the mongo dump on the new server, and restore graylog's mongo database

systemctl stop graylog-server mongo graylog --eval "db.dropDatabase()" mongorestore -d graylog /home/lbkp/mongo/graylog/ systemctl start graylog-server