IT/Clustered Nextcloud

Clustered Nextcloud

Why?

• more robust, a server can go down and Nextcloud still runs (depending on implementation)

Why not?

• needs more hardware (at least 3 nodes for e.g. Galera)
• more complex

Upgrade Paths

• Distributed DB
  • MariaDB clustered with Galera
  • it was only recommended to use only 1 DB node for writes with all instances (Galera does not support WRITE_COMMIT which Nextcloud depends on)
    • that may have changed since, but there seems to be no public documentation for clustering for newer versions (since this is probably more for enterprise customers)
  • read can be done from all DB nodes
• Distributed FS
  • GlusterFS
  • Ceph
  • ...
  • Alternatively just shared filestorage e.g. NFS
  • Alternatively SyncThing (maybe more for a Active-Failover Setup with high latency inbetween?)
• Load Balancer/Failover
  • HAProxy
  • Keepalived

Ressources

• Example project: https://help.nextcloud.com/t/help-me-test-this-3-node-cluster/12863/48
• HAProxy: https://www.haproxy.com/blog/how-to-run-haproxy-with-docker
• Keepalived (VRRP service): https://www.keepalived.org/