The best replacement for mysql cluster is oracle rac.

The best alternatives to mysql cluster are rated as following:
★★★★★  oracle rac
★★★★★  community server
★★★★  percona xtradb cluster
★★  communityserver
★★  galera
★★  mysql community server
★  mariadb galera
★  drbd
★  postgresql cluster

Your alternative for mysql cluster is not listed? Suggest!
Speaking about mysql cluster, one probably shouldn't forget about haproxy.

Other search terms related to mysql cluster and their ratings are:
★★★★★ haproxy
You have in mind a companion for mysql cluster and it is not yet here? Propose!



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mysql cluster
oracle rac
community server