This particular ticket doesn't necessarily deal with high availability or failing from one guacd server to another, just being able to assign a connection to a particular guacd instance, as might be necessary to overcome firewall issues and deal with distributed networks, and as is necessary for implementing the X.org driver.
You're asking about two other things, which are probably good things to implement, but separate from this particular ticket and probably separate from each other:
- Ability to load-balance or at least fail over from one guacd instance to another. guacd doesn't really care about where the client is getting its connection information (MySQL, PostgreSQL, LDAP, etc.), it just receives the Guacamole protocol information from the client and processes the translation of the Guacamole protocol to whatever back-end you're connecting to (SSH, RDP, etc.).
- Ability to load-balance the Guacamole client and share sessions and configuration information between multiple instances of the client. This is likely already possible to some degree, although I'm not entirely sure how safe it is. There are some things that probably wouldn't work correctly - like tracking active connections - and some others that might be unsafe - like multiple admins editing the same connections.
Anyway, probably worth opening a couple of separate tickets for these issues.