itamae/cookbooks/consul/files/etc/consul.d/check-reboot-required.json

{
  "check": {
    "id": "reboot-required",
    "name": "Check for Reboot Required",
    "args": ["/usr/local/bin/check_file", "/var/run/reboot-required"],
    "interval": "86400s",
    "timeout": "10s"
  }
}