+++
date = "2019-05-02T22:19:54+00:00"
publishdate = "2023-12-29T07:08:55+00:00"
title = "Automate Vultr Snapshots Using Bash"
slug = "automate-vultr-snapshots-using-bash"
author = "Thedro"
tags = ["bash","hosting"]
type = "posts"
summary =  "Vultr is a VPS (Virtual Private Server) hosting platform that uses KVM (Kernel-based Virtual Machine) Virtualization."
draft =  ""
syntax =  "1"
toc =  ""
updated =  "2022-08-14"
+++

{{< mark >}}
**Note**: This article is out of date.
[Vultr's `API` v1 end of life was announced June 30, 2023](https://www.vultr.com/docs/vultr-api-v1-to-v2-transition-strategies/)
{{< /mark >}}

- - -

![Vultr Snapshot Dashboard](/images/automate-vultr-snapshots-using-bash.png "
  Vultr Snapshot Dashboard"
)

[Vultr](https://www.vultr.com/) is a VPS (Virtual Private Server) hosting
platform that uses KVM (Kernel--based Virtual Machine) virtualization. Signing
into their website over and over again to make a snapshot can be tedious. Let's
automate this process using
[`bash`,](<https://en.wikipedia.org/wiki/Bash_(Unix_shell)>) and
[`systemd`](https://en.wikipedia.org/wiki/Systemd) timers.

Vultr offers an excellent
[`API` (Application Programming Interface)](https://www.vultr.com/api/) that
lets you programmatically orchestrate a web based hypervisor dashboard, right
down to account payments. We will use this `API` to automatically create
snapshots.

**Update**: Vultr's {{< sidenote mark="snapshots" set="left" >}}Other low level
methods for snapshotting exist. This is merely a nice
convenience.{{< /sidenote >}} used to be free, but
[the pricing changed](https://www.vultr.com/news/Vultr-will-begin-charging-for-snapshot-storage-on-October-1/)
to `$0.05/GB` per month. Keeping this in mind the script below sets an
{{< sidenote mark="initial" set="right" >}}Vultr used to support up to `11` free
snapshots.{{< /sidenote >}} limit of `11` snapshots.

{{< image source="/images/vultr-snapshot-notice.png" title="Vultr Snapshot Disclaimer" >}}
Vultr Snapshot Disclaimer {{< /image >}}

First let's set up the variables that our script will use to create and rotate
snapshots.

```bash
#!/bin/sh -eu

Key='YourAPIKEY'
SnapshotLimit=11
SnapshotCount=$(curl -s -H "API-Key: $Key" https://api.vultr.com/v1/snapshot/list | grep -o SNAPSHOTID | wc -l)
Fields=$(curl -s -H "API-Key: $Key" https://api.vultr.com/v1/snapshot/list | grep -o '"' | wc -l)
LastSnapshotField=$((Fields - 24))
LastSnapshotID=$(curl -s -H "API-Key: $Key" https://api.vultr.com/v1/snapshot/list | grep '"' | cut -d '"' -f $LastSnapshotField)
```

We are using command substitutions with `curl`. Let's add our `API` key and set
the snapshot limit to `11`. The `API` will respond in `json`. We can install
[jq](https://stedolan.github.io/jq/) but I'll use the tools that are available
to process the output. First, we'll get the current number of snapshots using
`grep` and `wc`.

```bash
SnapshotCount=$(curl -s -H "API-Key: $Key" https://api.vultr.com/v1/snapshot/list | grep -o SNAPSHOTID | wc -l)
```

Then use the same technique to get the number of fields in the `json` output
delimited by `"`.

```bash
Fields=$(curl -s -H "API-Key: $Key" https://api.vultr.com/v1/snapshot/list | grep -o '"' | wc -l)
```

Since we have an upper snapshot limit of `11`, we also need to know the `ID` of
the oldest snapshot. This will allow us to destroy that snapshot when we reach
the limit automatically. I already know that the oldest snapshot `ID` is always
`28` fields away from the end of the delimited `json` output.

```bash
LastSnapshotField=$((Fields - 28)
```

Finish up by using `grep` and `cut` to extract the oldest snapshot `ID`.

```bash
LastSnapshotID=$(curl -s -H "API-Key: $Key" https://api.vultr.com/v1/snapshot/list | grep '"' | cut -d '"' -f $LastSnapshotField)
```

Execute a simple `if` statement to destroy that snapshot when necessary. Nothing
fancy.

```bash
if [ "$SnapshotCount" -eq "$SnapshotLimit" ]
  then
    curl -H "API-Key: $Key" https://api.vultr.com/v1/snapshot/destroy --data "SNAPSHOTID=$LastSnapshotID" || exit 1;
fi

curl -H "API-Key: $Key" https://api.vultr.com/v1/snapshot/create --data 'SUBID=YourSUBID';
```

Our full script now looks like this and is complete.

```bash
#!/bin/sh -eu

Key='YourAPIKEY'
SnapshotLimit=11
SnapshotCount=$(curl -s -H "API-Key: $Key" https://api.vultr.com/v1/snapshot/list | grep -o SNAPSHOTID | wc -l)
Fields=$(curl -s -H "API-Key: $Key" https://api.vultr.com/v1/snapshot/list | grep -o '"' | wc -l)
LastSnapshotField=$((Fields - 24))
LastSnapshotID=$(curl -s -H "API-Key: $Key" https://api.vultr.com/v1/snapshot/list | grep '"' | cut -d '"' -f $LastSnapshotField)

if [ "$SnapshotCount" -eq "$SnapshotLimit" ]
  then
    curl -H "API-Key: $Key" https://api.vultr.com/v1/snapshot/destroy --data "SNAPSHOTID=$LastSnapshotID" || exit 1;
fi

curl -H "API-Key: $Key" https://api.vultr.com/v1/snapshot/create --data 'SUBID=YourSUBID';
```

Let's drop this into a `systemd` service at
`/etc/systemd/system/vultr-snapshot.service`.

```ini
[Unit]
Description=Create Vultr Snapshot

[Service]
Type=oneshot
ExecStart=/usr/local/bin/vultr-snapshot
```

Then run it using a timer at `/etc/systemd/system/vultr-snapshot.timer`. This
timer runs the script at `5:30 AM` every morning.

```ini
[Unit]
Description=Create Vultr Snapshot

[Timer]
OnCalendar=*-*-* 05:30:00
RandomizedDelaySec=60

[Install]
WantedBy=timers.target
```

That's it. This is a quick way of supplementing your normal backups with
automatic Vultr snapshots.