[AMQ-160] Trouble with duplicate clientIds and ReliableConnections

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 1.4
• Fix Version/s: 2.0
• Component/s: Broker, JMS client
• Assignee: Unassigned
• Reporter: Dag Liodden
• Created: 17/Dec/04 02:18
• Updated: 20/Nov/06 05:33
• Resolved: 07/Jan/05 00:55

Description

I tried this:

1. Setup a broker using tcp-transport on one machine
2. Start a client using reliable transport and a client id on another machine (same LAN)
3. Pull the network plug on the client

• Client connection is terminated on the client side
• Broker doesn't notice
  4. Plug the client back into the network
• Reliable connection reconnects
• Broker throws InvalideClientIDException
  5. Send a message to the Broker
• Client disconnect is detected by the broker and client is removed
  6. Reconnect client
• Works now

Possible solutions from the top of my head:

1. When connecting with duplicate client ids, kick the existing client out (could lead to pseudo-race conditions if clients are incorrectly configured to use duplicate ids and reliable is enabled)
2. Do an explicit, syncrhonized keepalive packet send on the existing connection when a duplicate client connects, if the existing client is down, kick it and allow the new client to connect, otherwise do as normal

Number 2 is probably best and I'll implement it if you agree that this is a reasonable solution.