autoscale-do-block-storage/README.md

# checkvolumesize

> Autoscale Digital Ocean block storage volumes

Create a Digital Ocean block storage volume and write as much data to it as you want. Run this script on cron to monitor the volume and automatically scale it up in size as required with zero downtime.

Don't worry about manually resizing or running out of space and save money by only paying for what you use.

Inspired by this feature request:
- https://twitter.com/lukechilds/status/1192252814262599680
- https://ideas.digitalocean.com/ideas/BSX-I-6

## Usage

```
$ checkvolumesize --help
checkvolumesize 1.0.0

Automatically expand Digital Ocean block storage volumes.

Usage: checkvolumesize [options]

Options:

  --help | -h | help    [Optional] Show this help message
  --token               [Required] Digital Ocean API token
  --device              [Required] The volume's block device or mount point
  --volume-name         [Required] The volume's name
  --volume-region       [Required] The volume's region
  --buffer              [Optional] The amount of GB to keep available    Default: 10
  --log                 [Optional] Prepend timestamps to stdout

Example:

  checkvolumesize /
    --token bc99be9f73b037da64074472fe58f643e619328b85c5467615964a59abd12029 /
    --device /mnt/block-storage /
    --volume-name volume-sgp1-01 /
    --volume-region sgp1 /
    --buffer 10

GitHub: https://github.com/lukechilds/autoscale-do-block-storage
```

## Demo

```
$ checkvolumesize --token bc99be9f73b037da64074472fe58f643e619328b85c5467615964a59abd12029 --device /dev/sda --volume-name volume-sgp1-01 --volume-region sgp1 --buffer 10
Checking available space on device "/dev/sda" is above 10GB requirement...
Only 8GB available, volume resize required
Getting data for volume "volume-sgp1-01" in region "sgp1"...
Volume ID is "2cbebc6a-ff42-11e9-a238-0a58ac14a19d" and is currently 430GB
Increasing volume size to 440GB...
Created action "796611989"
Waiting for action to complete...
Volume resize complete!
Resizing filesystem...
resize2fs 1.44.1 (24-Mar-2018)
Filesystem at /dev/sda is mounted on /mnt/volume_sgp1_01; on-line resizing required
old_desc_blocks = 54, new_desc_blocks = 55
The filesystem on /dev/sda is now 115343360 (4k) blocks long.
Filesystem resize complete!
Device "/dev/sda" now has 17GB available
Completed in 16 seconds
```

## Installation

Clone this repo and add `checkvolumesize` to your path. Then add a cron job as root.

```
*/10 * * * * checkvolumesize [options] --log >> /var/log/checkvolumesize.log
```

You may also need to add:

```
PATH=/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin
```

to your root crontab for the script to be able to find the `resize2fs` binary.

You can view the log in `/var/log/checkvolumesize.log`

```
2019-11-07 11:30:01 Checking available space on device "/dev/sda" is above 10GB requirement...
2019-11-07 11:30:01 19GB available, all good!
2019-11-07 11:40:01 Checking available space on device "/dev/sda" is above 10GB requirement...
2019-11-07 11:40:01 Only 8GB available, volume resize required
2019-11-07 11:40:01 Getting data for volume "volume-sgp1-01" in region "sgp1"...
2019-11-07 11:40:03 Volume ID is "2cbebc6a-ff42-11e9-a238-0a58ac14a19d" and is currently 430GB
2019-11-07 11:40:03 Increasing volume size to 440GB...
2019-11-07 11:40:10 Created action "796611989"
2019-11-07 11:40:10 Waiting for action to complete...
2019-11-07 11:40:17 Volume resize complete!
2019-11-07 11:40:17 Resizing filesystem...
2019-11-07 11:40:17 resize2fs 1.44.1 (24-Mar-2018)
2019-11-07 11:40:17 Filesystem at /dev/sda is mounted on /mnt/volume_sgp1_01; on-line resizing required
2019-11-07 11:40:17 old_desc_blocks = 54, new_desc_blocks = 55
2019-11-07 11:40:17 The filesystem on /dev/sda is now 115343360 (4k) blocks long.
2019-11-07 11:40:17 Filesystem resize complete!
2019-11-07 11:40:17 Device "/dev/sda" now has 17GB available
2019-11-07 11:40:17 Completed in 16 seconds
2019-11-07 11:50:01 Checking available space on device "/dev/sda" is above 10GB requirement...
2019-11-07 11:50:01 17GB available, all good!
```

## License

MIT © Luke Childs