hermes-skills/devops/mariadb-galera-cluster-administration/references/galera-cluster-topology.md

Homelab Galera/MaxScale Topology (Updated 2026-07-13)

MariaDB Galera Cluster (3 nodes — quorum-safe: 3 different PVE hosts)

Node	VM ID	Proxmox Host	IP	Hostname	RAM
db1	300	n5pro (10.0.20.91)	10.0.30.71	mariadb-01	8 GB
db2	301	proxmox3 (10.0.20.30)	10.0.30.72	mariadb-02	8 GB
db3	302	proxmox6 (10.0.20.60)	10.0.30.73	mariadb-03	8 GB

• MariaDB version: 11.4.10-MariaDB-deb12
• Cluster name: mariadb-galera
• Galera address: gcomm://10.0.30.71,10.0.30.72,10.0.30.73
• DB size: ~18GB (homeassistant schema)
• Effective RAM usage: ~5.5 GB per node (4 GB innodb_buffer_pool + 1.5 GB OS/Galera)
• balloon: 0 on all Galera VMs — see SKILL.md §5.3b for rationale
• Quorum guarantee: Any single PVE host failure leaves ≥2 Galera nodes alive
• Note: PVE HA may migrate VMs. Always verify current placement with qm list on each node before operating.

MaxScale Proxy (2 instances + VIP)

Node	VM ID	Proxmox Host	IP	Hostname	RAM	Status
maxscale-01	310	n5pro (10.0.20.91)	10.0.30.81	maxscale-01	2 GB	Active
maxscale-02	311	proxmox3 (10.0.20.30)	10.0.30.82	maxscale-02	2 GB	Standby
VIP	—	—	10.0.30.70	keepalived VIP	—	—

• MaxScale version: 24.02.9
• Services: rw-router (readwritesplit), ro-router (readconnroute)
• Monitor: galera-monitor (galeramon)
• Listener: rw-listener on port 3306

HA Rules (PVE 8 rules.cfg)

node-affinity: db-nodes
    nodes n5pro,proxmox3,proxmox6
    resources vm:300,vm:301,vm:302,vm:310,vm:311
    strict 1

resource-affinity: ha-rule-ea9e852a-8d82
    affinity negative
    resources vm:310,vm:311

resource-affinity: ha-rule-d61699eb-2baf
    affinity negative
    resources vm:301,vm:302

• db-nodes (strict=1): Galera + MaxScale VMs restricted to n5pro + proxmox3 + proxmox6 (3 hardware-diverse hosts)
• Negative resource-affinity: MaxScale 310↔311 kept apart, Galera 301↔302 kept apart
• At node failure, HA manager restarts VM on one of the other 2 allowed nodes (deterministic)
• ⚠️ Anti-affinity rules can block qm migrate — check rules.cfg before migrating

PVE Host RAM Capacity

Host	IP	Physical RAM	Notes
n5pro	10.0.20.91	91 GB	Massive headroom, primary DB host
proxmox3	10.0.20.30	31 GB	Good headroom, secondary DB host
proxmox6	10.0.20.60	15 GB	Tight — 113% overcommit with Galera VM, but effective use is only 5.5 GB
proxmox1-2,4-5,7	10.0.20.{10,20,40,50,??}	15 GB each	NOT in db-nodes rule — DB VMs cannot failover here

SSH Access

# MariaDB VMs (user: debian) — may vary if HA migrated the VM
ssh -i ~/.ssh/id_ed25519_proxmox debian@10.0.30.71
ssh -i ~/.ssh/id_ed25519_proxmox debian@10.0.30.72
ssh -i ~/.ssh/id_ed25519_proxmox debian@10.0.30.73

# MaxScale VMs (user: debian)
ssh -i ~/.ssh/id_ed25519_proxmox debian@10.0.30.70

# Proxmox hosts (user: root)
ssh -i ~/.ssh/id_ed25519_proxmox root@10.0.20.10   # proxmox1
ssh -i ~/.ssh/id_ed25519_proxmox root@10.0.20.30   # proxmox3
ssh -i ~/.ssh/id_ed25519_proxmox root@10.0.20.60   # proxmox6
ssh -i ~/.ssh/id_ed25519_proxmox root@10.0.20.91   # n5pro

Credentials

Credentials in 1Password Vault "Kubernetes ESO" (ID: 334ykdtj5kar3jlpcrztjvx2fu):

• mariadb-root — root password (localhost only, sudo mariadb on node)
• mariadb-app-user — username=dominik, app access
• gitea-db — Gitea database user/password

Legacy item mariadb-galera-vm in vault "Hermes" may still contain:

• maxscale-password — MaxScale MySQL user with SUPER privilege
• mariabackup-password — Galera SST transfer auth
• ha-recorder-password — HA Recorder MySQL user
• keepalived-auth-pass — keepalived VIP failover auth

Firewall (UFW on MariaDB VMs)

• Port 3306: ALLOW from 10.0.30.81, 10.0.30.82 (MaxScale only)
• Ports 4567, 4568, 4444: ALLOW between Galera nodes (10.0.30.71-73)

Home Assistant

• VM 106 on proxmox1 (10.0.20.10)
• Internal: http://10.0.30.10:8123
• External: https://homeassistant.familie-schoen.com
• Config: /mnt/data/supervisor/homeassistant/configuration.yaml
• Recorder DB URL: mysql://ha_recorder:***@10.0.30.70:3306/homeassistant
• InfluxDB: 10.0.30.109:8086, bucket ha_hot_90d (long-term history)

HAOS SSH Access (Port 22222)

ssh -i ~/.ssh/id_ed25519_proxmox root@10.0.30.10 -p 22222