Keepalived with Nomad

client.hcl

client {
    enabled = true

    node_class = ""
    no_host_uuid = false

    servers = ["10.253.155.163","10.253.155.17","10.253.155.102"]

    max_kill_timeout = "30s"

    network_speed = 0
    cpu_total_compute = 0

    gc_interval = "1m"
    gc_disk_usage_threshold = 80
    gc_inode_usage_threshold = 70
    gc_parallel_destroys = 2

    reserved {
        cpu = 0
        memory = 0
        disk = 0
    }

    meta {
        keepalived_priority = 150
    }

}

plugin "docker" {
    config {
        allow_caps = ["CHOWN","DAC_OVERRIDE","FSETID","FOWNER","MKNOD","NET_RAW","SETGID","SETUID","SETFCAP","SETPCAP"," NET_BIND_SERVICE","SYS_CHROOT","KILL","AUDIT_WRITE","NET_ADMIN"]
    }
}

keepalived.nomad

job "keepalived" {
    datacenters = ["dc1"]
    type = "system"

    group "keepalived" {
        task "keepalived" {
            driver = "docker"
            config {
                image = "osixia/keepalived:2.0.20"
                network_mode = "host"
                volumes = [
                    "local/:/container/environment/01-custom"
                ]
                cap_add = ["NET_ADMIN"]
            }
            template {
                destination = "local/env.yaml"
                change_mode = "restart"
                splay       = "1m"
                data        = <<EOH
KEEPALIVED_VIRTUAL_IPS:
  - 10.253.155.254/24

KEEPALIVED_UNICAST_PEERS:
{{- with $node := node -}}
{{ range nodes }}
{{- if ne .Address $node.Node.Address }}
  - {{ .Address }}
{{- end -}}
{{- end -}}
{{- end }}

KEEPALIVED_PRIORITY: {{ env "meta.keepalived_priority" }}

KEEPALIVED_INTERFACE: {{ sockaddr "GetPrivateInterfaces | include \"network\" \"10.253.155.0/24\" | attr \"name\"" }}
EOH
            }
        }
    }
}