Open Infrastructure

h1. The ungleich cdist trigger server guide

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h2. What is cdist trigger server

The cdist trigger server can be used for autonomous configuration of hosts. Unlike the "normal" procedure of cdist, where a human being or a control server itself starts cdist for the configuration, the cdist trigger server waits until it gets triggered (therefore the name) by a host which wants to be configured. 

The trigger server takes the IP from the requester and first tries to resolve the IP to a FQDN (via the reverse zone). The FQDN (or the IP if reverse lookup didn't work out) is then used for the cdist configuration (same as @cdist config HOSTNAME@)

h2. Where do we use it

We at ungleich, we use the cdist trigger server currently for our server startup chain (See: [[The ungleich server OS setup]]

Where the netbooted server will trigger the trigger server and then gets fully configured.

h2. How to get

Cdist trigger server is currently in beta phase. This means you have to clone the repository ("cdist":github.com:ungleich/cdist.git) and checkout the beta branch

<pre>

git clone git@github.com:ungleich/cdist.git

cd cdist

git checkout beta

</pre>

h2. How to configure

The simplest usage is the following

<pre>

cdist trigger -b -H 3000 --ipv6

</pre>

This will start the server, listen on port 3000 and also enable IPv6

If you have the configuration files not in the default location (@~/.cdist@), use the @-c@ parameter

h2. Nice additional configurations

Since the trigger server needs access to the host which is going to be configured, the trigger server ssh key needs to be deployed in before.

Simplest solution is to create a small webserver, which provides the public key from the trigger server.

Therefore the host have to get and install the ssh key before it triggers the cdist trigger server.

h2. Resources

# "cdist trigger man":https://www.nico.schottelius.org/software/cdist/man/beta/cdist-trigger.html

# "cdist preos man":https://www.nico.schottelius.org/software/cdist/man/beta/cdist-preos.html