DNS failover & traffic cutover

Manual cutover

Make active on a standby member → ServerCTL sets it as primary and updates the managed A record to its public IPv4.

Cut DNS to standby on Overview → promotes next failover-ready standby (same DNS update, overview-oriented workflow).

Automatic failover

Enable in Settings → Balancer failover.

When enabled, ServerCTL periodically evaluates the active member. Promotion triggers when:

Heartbeat age exceeds failover delay, or
HAProxy is monitored and inactive

A healthy standby is promoted; DNS is updated; optional email alert fires.

Failover delay

Setting	Range
Recovery time	10–120 seconds
Community (free)	Fixed at 120s
Pro / trial	Faster presets (e.g. 10s, 30s)

Agents' heartbeat independently (~1s); failover delay is not the heartbeat interval.

Failover-ready criteria

A standby is ready when:

Recent heartbeat within the failover window, and
HAProxy is not down (when monitored)

Dynamic DNS Sync

Optional for HAProxy pools when the active member’s WAN IPv4 changes (DHCP/ISP churn). Each heartbeat can push the new public IP to Cloudflare without manual DNS edits.

Proxied vs DNS-only

Orange cloud (proxied): Traffic through Cloudflare; good for HTTP/S when origin IP hiding matters.
DNS-only (grey cloud): Clients connect directly to member IPv4 — required for raw TCP services (e.g. non-HTTP on custom ports).

Revision #2
Created 2026-06-16 00:56:00 UTC by ServersCTL
Updated 2026-06-17 20:22:02 UTC by ServersCTL