Venue Failover

[Ivan R. Judson]

Here's the simple mechanism I was planning on inserting for venue failover,
I've followed that up with open issues and concerns. I'd like to get
feedback on how to close the open issues.

1. Add to the Venue Server config file: BackupServer: <hostname>
2. the Backup server gets the exact same venue configuration as the
original, updates are the responsibility of the administrator. No magic will
take care of that for now.
3. The backup server is part of the venuestate that is received by the
client upon entering the venue.

Behavior:

If the venue client detects a break of the event channel, then:

1. it tries 3 times to reconnect to the original server, if that fails
2. it tries to connect to the backup server.

Open Issues:

How to revert back to the original server?

Ideas:

1. don't bother
2. retry at some interval (the trickle of users back would be disturbing)
3. ???

Concerns:

1. Media tools should not stop and restart (it's disruptive)

Thoughts?

--Ivan