It’s my understanding that XtraDB Cluster 5.5 is not “actively” developed anymore, but does this include major security patches as well? I see that there was an upgrade pushed every few months to include more recent bug and security fixes, but I can’t find any information on how often, if at all they are planned to be released. If it’s no longer being supported at all, I believe the 5.5 documentation should have a very clear warning message for users, since I have been searching for nearly an hour an still have no idea if 5.5 has any support, security or otherwise. MySQL 5.5 and your own Percona Server for MySQL 5.5 appear to still be receiving security updates, which would lead me (and I’d assume many other people) to believe XtraDB CLuster 5.5 would also receive those updates.