[[!meta title="How to enable encrypted swap in Alpine Linux"]]

## TL;DR

There is no TL;DR, because it is so easy that any summary would be too
long.

The steps are so simple:

### Edit /etc/conf.d/dmcrypt

Checkout the samples and enable swap like this:

    swap=crypt-swap
    source='/dev/nvme0nXXX'

(obviously set the correct *source* device)

### Start dmcrypt

Run

    /etc/init.d/dmcrypt start

### Enable swap

    swapon /dev/mapper/crypt-swap


### Make it persistent

    # Enable automatic start of encryption & swap
    rc-update add dmcrypt
    rc-update add swap

    # Enable automatic swapon
    echo /dev/mapper/crypt-swap swap swap defaults 0 0 >> /etc/fstab

## Background

Until today I did not know (or care) how to enable swap in Alpine
Linux. As firefox (sic!) is killing my system more often these days, I
decided to enable swap using a partition I left for it some years ago.

As I did not know how it works, I grep'ed for crypt through
/etc/init.d, found the dmcrypt init script quickly which references
/etc/conf.d/dmcrypt. I opened the config file and within minutes my
encrypted swap was up.

Note that above instructions will reset/re-encrypt swap on every boot
and thus no suspend to disk works with it. That's fine with me, as
that is not a feature I am ever going to use.

The point I need to make is that at the moment there is no single
other Linux distribution out there that I know off that is allowing me
to make changes, even those which I don't know yet how to, that easily
and I want to say many thanks for keeping Alpine Linux as simple as
other Linux distributions used to be in the 90's.

[[!tag alpinelinux security]]