MariaDB 10.1.8 fails to join an existing MariaDB 10.0.21 cluster for migration.
With the existing cluster environment up and running, I built two parallel VMs to test joining. Both have fresh installs from the Debian 8.2 netinst.iso. After ISO installation completed, SSH was installed for ease of access.
From here, each of the VMs were configured per instructions on this page: https://downloads.mariadb.org/mariadb/repositories/
The only difference in the two VMs is the reference to "10.0" and "10.1" in the source repository and the packages installed - "mariadb-galera-server" on 10.0 and "mariadb-server" on 10.1
The following file was created with contents below on each VM: /etc/mysql/conf.d/galera.cnf
After creating this file, the mariadb server was restarted on each VM.
The MariaDB 10.0.21 VM joined the cluster without issue.
The MariaDB 10.1.8 VM failed to join the cluster. Log file attached.