Drupal VM makes using Apache Solr easy; just make sure solr is in the list of installed_extras in your config.yml, and when you build Drupal VM, the latest version of Apache Solr will be installed.

Inside of Drupal, you can use any of the available Apache Solr integration modules (e.g. Apache Solr Search or Search API Solr Search), and when you configure the modules, follow the installation instructions included with the module.

The URL to connect to the local solr server (assuming you're using the default solr_port of 8983) from Drupal is:

http://localhost:8983/solr/collection1

This will connect to the default search core (collection1) set up by Solr. If you are using a multisite installation and want to have a search core per Drupal site, you can add more cores through Apache Solr's admin interface (visit http://drupalvm.dev:8983/solr/), then connect to each core by adding the core name to the end of the above URL (e.g. core2 would be http://localhost:8983/solr/core2).

Configuring the Solr search core for Drupal

Before Drupal content can be indexed correctly into Apache Solr, you will need to copy the Drupal Apache Solr Search or Search API Apache Solr configuration into place, and restart Apache Solr. Drupal VM comes with an example post provision script for automating this. Simply add it to post_provision_scripts:

post_provision_scripts:
 - "../examples/scripts/configure-solr.sh"

Extra Solr configuration

You can add extra configuration for Solr, like the minimum and maximum memory allocation for the JVM (solr_xms and solr_xmx), and even the solr_version, by setting the appropriate variables inside config.yml before you build Drupal VM.