Server: Should I add users to the existing application or federate?
When should I use the same application to add users and when should I federate applications?
Here are some pros and cons of using the same instance vs federating:
Pros and cons of using single application:
- Licensing: If some users need access to all information, having single instance allows you to license each user only once. Federated instance requires the same user that needs access to both instances (two separate application deployments) to be licensed in each system. Atlassian applications do not support two single server application deployments sharing one Server license (see Do we need extra licenses for multiple instances of software installation on a single server?).
- User permissions: Adding users into an existing deployment allows you to use any existing groups, spaces, and permissions. A new system might require new permissions set up depending on your requirements.
- User mentions: because all users are available in the same system, all users can interact with each other where allowed by global and space permissions.
- Organizing and re-organizing content: You can take advantage of Confluence's automatic page link suggestions and auto completion features when creating content. Because all content is in a single instance the content is recognized and suggested. You can also easily take advantage of creating document draft spaces and moving published content to under space via the built-in page move functionality.
Pros and cons of federating applications:
- When you're concerned about potential user error of space permissions and page restrictions set up and accidentally revealing, for example, internal content to external users, it is best to set up a federated instance.
- The same user in both application deployments needs to be licensed in each application. In essence, the single user consumes two licenses when accessing the two separate installations. To consume only one license, consider single deployment with appropriate permissions settings.
- Add-ons must be licensed at the same user tier as it's parent application. Federating systems can be cost effective if requirements dictate a completely separate set of plugins only required for small sub-set of users. If duplicate plugins are required in each system, consider single deployment as an option.
- Moving content from one instance to another requires a 3rd party plugin. It is not natively supported in Atlassian applications. For example, see JIRA to JIRA Issue Copy or Remote Publishing (requires a paid workflows plugin) for Confluence.
- If you have a requirement in Confluence around set of users not being able to 'discover' other set of users via user mentions and other user suggestion functionalities (user settings in macros, etc.) you'll want to use federated setup. Refer to feature suggestion: CONF-7837