There are several related causes for this, but it boils down to PuppetDB being unable to read your truststore.jks or keystore.jks file. The former file contains the certificate for your certificate authority, and is what PuppetDB uses to authenticate clients. The latter contains the key and certificate that PuppetDB uses to identify itself to clients.
The short answer: you can often fix these problems by reinitializing the keystore
and truststore, by running /usr/sbin/puppetdb-ssl-setup. Note that this script
must be run after a certificate is generated for the puppet agent (that is:
after the agent has run once and had its certificate request signed). A common
problem is installing PuppetDB before the Puppet agent has run, and this script
will solve that problem, and many others.
The long answer: if the puppetdb-ssl-setup script doesn't solve your problem
or if you're curious what's going on under the covers, you can manage this
configuration by hand. The locations of the truststore and keystore files are set
with the keystore and truststore options in the config file. There should
also be settings for key-password and trust-password. Make sure the
keystore.jks and truststore.jks files are where the config says they should be,
and that they're readable by the user PuppetDB runs as (puppetdb for an open
source installation, pe-puppetdb for a Puppet Enterprise installation).
Additionally, you can verify that the password is correct using
keytool -keystore /path/to/keystore.jks and and entering the key-password.
Similarly, you can use keytool -keystore /path/to/truststore.jks to verify the
truststore.
There are two common error cases with the dashboard:
- You're trying to talk over plaintext (8080) and PuppetDB's not listening
By default, PuppetDB only listens for plaintext connections on localhost, for security reasons. In order to talk to it this way, you'll need to either forward the plaintext port or change the interface PuppetDB binds on to one that is accessible from the outside world. In the latter case, you'll want to use some other means to secure PuppetDB (for instance, by restricting which hosts are allowed to talk to PuppetDB through a firewall).
- You're trying to talk over SSL and nobody trusts anybody else
Because PuppetDB uses the certificate authority of your Puppet infrastructure, and a certificate signed by it, PuppetDB doesn't trust your browser, and your browser doesn't trust PuppetDB. In this case, you'll need to give your browser a certificate signed by your Puppet CA. Support for client certificates is varied between browsers, so it's preferred to connect over plaintext, as outlined above.
Partially. Use with Puppet apply requires some special configuration, and due to limitations in Puppet, inventory service functionality isn't fully supported. Catalog storage and collection queries are completely functional, though. You can find information about configuring Puppet apply to work with PuppetDB in the installation guide for your version of PuppetDB.
Either of these issues can also be solved through clever and judicious use of proxies, although the details of that are left as an exercise to the reader.
Actually, PuppetDB isn't written in Java at all! It's written in a language called Clojure, which is a dialect of Lisp that runs on the Java Virtual Machine. Several other languages were prototyped, including Ruby and JRuby, but they lacked the necessary performance. We chose to use a JVM language because of its excellent libraries and high performance. Of the available JVM languages, we used Clojure because of its expressiveness, performance, and previous experience with the language on our team.
The officially supported versions are OpenJDK and Oracle JDK, versions 1.6 and 1.7. Other versions may work and issues will be addressed on a best effort basis, but support is not guaranteed.
PostgreSQL is the recommended database for production use. PuppetDB also ships with an embedded HyperSQL database which is suitable for very small or proof of concept deployments. As with our choice of language, we prototyped several databases before settling on PostgreSQL. These included Neo4j, Riak, and MySQL with ActiveRecord in Ruby. We have no plans to support any other databases, including MySQL, which lacks important features such as array columns and recursive queries