rancherOS/docs/os/configuration/resizing-device-partition/index.md

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title: Resizing a Device Partition in RancherOS layout: os-default

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Resizing a Device Partition

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The resize_device cloud config option can be used to automatically extend the first partition to fill the size of it's device.

Once the partition has been resized to fill the device, a /var/lib/rancher/resizefs.done file will be written to prevent the resize tools from being run again. If you need it to run again, delete that file and reboot.

#cloud-config
rancher:
  resize_device: /dev/sda

This behavior is the default when launching RancherOS on AWS.