vrrp_script chk_svc_port {
    # returns 1 if connection is refused
    script "/bin/bash -c '</dev/tcp/127.0.0.1/{{ service_port }}'"
    # check every 2 seconds
    interval {{ healthcheck_interval }}
    # make sure master priority drops below backup priority on failure
    weight 2
}
vrrp_instance VI_1 {
    interface {{ network_interface }}
    state {% if is_leader %}MASTER{% else %}BACKUP{% endif %}
    priority {% if is_leader %}101{% else %}100{% endif %}
    virtual_router_id {{ router_id }}

    virtual_ipaddress {
        {{ virtual_ip }}
    }

    track_script {
        chk_svc_port
    }
}