/etc/ha.d/authkeys is read by heartbeat(8). It enables Heartbeat to securely authenticate cluster nodes.

This file must not be readable or writable by any users other than root.


Two lines are required in the authkeys file:

A line which says which key to use in signing outgoing packets

One or more lines defining how incoming packets might be being signed.

The file must follow the following format:

auth num
num method secret
num method secret
num method secret

num is a numerical identifier, between 1 and 15 inclusive. It must be unique within the file.

method is one of the available authentication signature methods (see below for supported methods).

secret is an alphanumerical shared secret used to identify cluster nodes to each other.

authnum selects the currently active authentication method and secret.


The following signature methods are supported in authkeys (listed here in alphabetical order):


MD5 hash method. This method requires a shared secret.


SHA-1 hash method. This method requires a shared secret.


Cyclic Redundancy Check hash method. This method does not require a shared secret and is insecure; it's use is strongly discouraged.

An absolutely up-to-date list of authentication methods supported may be retrieved by running ls /usr/lib/heartbeat/plugins/HBauth/*.so.


Alan Robertson <[email protected]>

heartbeat, original Wiki page

Florian Haas <[email protected]>

man page