---
name: "amcrypt"
section: "8"
platform: "linux"
package: "amanda-common"
version: "1:3.5.4-2"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/amcrypt"
---

# amcrypt(8)

reference crypt program for Amanda symmetric data encryption

## NAME

amcrypt - reference crypt program for Amanda symmetric data encryption

## SYNOPSIS

**amcrypt**

## DESCRIPTION

**amcrypt** requires **aespipe**, **uuencode** and **gpg** to work. Aespipe is available from : http://loop-aes.sourceforge.net

**amcrypt** will search for the aespipe program in the following directories: /usr/bin:/usr/local/bin:/sbin:/usr/sbin.

**amcrypt** calls **amaespipe** and pass the **passphrase** through file descriptor 3. The passphrase should be stored in ~amanda/.am\_passphrase.

## HOW TO CREATE ENCRYPTION KEYS FOR AMCRYPT

1\. Create 65 random encryption keys and encrypt those keys using gpg. Reading from /dev/random may take indefinitely long if kernel's random entropy pool is empty. If that happens, do some other work on some other console (use keyboard, mouse and disks).

head -c 2925 /dev/random \| uuencode -m - \| head -n 66 \| tail -n 65 \\ \| gpg --symmetric -a \> ~amanda/.gnupg/am\_key.gpg

This will ask for a passphrase. Remember this passphrase as you will need it in the next step.

2\. Store the passphrase inside the home-directory of the AMANDA-user and protect it with proper permissions:

```
echo my_secret_passphrase > ~amanda/.am_passphrase
chown amanda:disk ~amanda/.am_passphrase
chmod 700 ~amanda/.am_passphrase
```

## KEY AND PASSPHRASE

**amcrypt** uses the same key to encrypt and decrypt data.

It is very important to store and protect the key and the passphrase properly. Encrypted backup data can **only** be recovered with the correct key and passphrase.

## SEE ALSO

[**amanda**(8)](/amanda/8.md), [**amanda.conf**(5)](/amanda.conf/5.md), [**aespipe**(1)](/aespipe/1.md), [**amaespipe**(8)](/amaespipe/8.md), [**gpg**(1)](/gpg/1.md)

The Amanda Wiki: : http://wiki.zmanda.com/

## AUTHOR

**Kevin Till** \<kevin.till@zmanda.com\>

Zmanda, Inc. (http://www.zmanda.com)