Note: In a true HA setup, 0.0.0.0:8443 is bound on all nodes, but only the VIP owner routes traffic. Install Keepalived on both nodes:

This article dissects every component of the Realm Host V2 HA Tunnel. You will learn what it is, how the architecture works, step-by-step configuration for active-passive and active-active clusters, and advanced troubleshooting. Before diving into HA tunnels, we must understand the core tool.

Introduction: The Need for Uninterrupted Connectivity In the modern era of edge computing, microservices, and remote work, a single point of failure in your network gateway is no longer acceptable. Whether you are running a home lab, a corporate VPN, or a geo-distributed proxy mesh, downtime translates directly to lost productivity or revenue.

, use state BACKUP and priority 100 . This ensures the VIP floats only to the node where the Realm daemon is healthy. Step 4: Systemd Service for Automatic Restarts Create /etc/systemd/system/realm-ha.service :

[Unit] Description=Realm Host V2 HA Tunnel After=network-online.target etcd.service keepalived.service [Service] Type=simple User=realm Group=realm ExecStartPre=/bin/mkdir -p /var/log/realm ExecStart=/usr/local/bin/realm -c /etc/realm/config.toml Restart=on-failure RestartSec=10 LimitNOFILE=65536