Unable to install add-on after setting up external database

Cause: The uploaded add-on size exceeds the default packet size limit in the database.

Resolution: Packet size setting by default in the database is not big enough to allow installation of add-ons in the Atlassian application. Please increase the packet size in the database.

For example, in MySQL, you can do this by editing MySQL’s my.cnf file (often named my.ini on Windows operating systems), Locate the [mysqld]section in the file, and add/modify the following parameters: max_allowed_packet=256M