cloud-config.yaml

#cloud-config

write_files:
  - path: /var/lib/cloud/scripts/prom_vdlimit_metrics.sh
    permissions: 0700
    owner: root:root
    content: |
      #!/bin/bash
      VDLIMIT_TEXT=""
      VDLIMIT_FILE="/var/spool/node_exporter/vdlimit.prom"
      USED=$(df --output="used" /mnt/stateful_partition | tail -n1 )
      FREE=$(df --output="avail" /mnt/stateful_partition | tail -n1 )
      SIZE=$(df --output="size" /mnt/stateful_partition | tail -n1 )
      VDLIMIT_TEXT="vdlimit_used{experiment=\"ndt.iupui\"} ${USED}\n"
      VDLIMIT_TEXT+="vdlimit_free{experiment=\"ndt.iupui\"} ${FREE}\n"
      VDLIMIT_TEXT+="vdlimit_total{experiment=\"ndt.iupui\"} ${SIZE}\n"
      echo -e $VDLIMIT_TEXT > $VDLIMIT_FILE
  - path: /etc/systemd/system/prom-vdlimit-metrics.service
    permissions: 0644
    owner: root:root
    content: |
      [Unit]
      Description=Writes vdlimit Prom metrics to /var/spool/node_exporter/vdlimit.prom
      [Service]
      Type=oneshot
      ExecStart=/var/lib/cloud/scripts/prom_vdlimit_metrics.sh
  - path: /etc/systemd/system/prom-vdlimit-metrics.timer
    permissions: 0644
    owner: root:root
    content: |
      [Unit]
      Description=Run /usr/bin/prom_vdlimit_metrics.sh every 5 minutes.
      [Timer]
      OnBootSec=1min
      OnUnitActiveSec=5min
      [Install]
      WantedBy=multi-user.target

# The iptables command below is necessary due to the way that the Google
# Container-Optimized OS works. For COS, it is necessary to both open holes in
# the VPC firewall as well as opening the firewall on the VM itself.
# https://cloud.google.com/container-optimized-os/docs/how-to/firewall
runcmd:
  - systemctl daemon-reload
  - systemctl enable prom-vdlimit-metrics.service
  - systemctl enable prom-vdlimit-metrics.timer
  - systemctl start prom-vdlimit-metrics.service
  - systemctl start prom-vdlimit-metrics.timer
  - iptables -A INPUT -p tcp -j ACCEPT