Solr scripts for cloud example break if called from a directory other than $SOLR_HOME, ie $PWD is not $SOLR_HOME: It always strips off the beginning of the path. This used to work regardless in Solr 4.x as I used to use it quite a lot and my custom solr 4.x docker containers it still works regardless of $PWD - it's only broken in 5x/6.0.
Here is an example of the issue:
docker run -ti solr bash solr@5083b8e59d49:/opt/solr$ cd / solr@5083b8e59d49:/$ solr -e cloud Welcome to the SolrCloud example! This interactive session will help you launch a SolrCloud cluster on your local workstation. To begin, how many Solr nodes would you like to run in your local cluster? (specify 1-4 nodes) : Ok, let's start up 2 Solr nodes for your example SolrCloud cluster. Please enter the port for node1 : Please enter the port for node2 : Creating Solr home directory /opt/solr/example/cloud/node1/solr Cloning /opt/solr/example/cloud/node1 into /opt/solr/example/cloud/node2 Starting up Solr on port 8983 using command: /opt/solr/bin/solr start -cloud -p 8983 -s "pt/solr/example/cloud/node1/solr" Solr home directory pt/solr/example/cloud/node1/solr not found! ERROR: Process exited with an error: 1 (Exit value: 1)