Issue

Fuse and A-MQ support a simple file-locking active/standby mode of operation, that ensures that only one container in a group can be active at the same time. This mechanism is intended for simple failover set-ups. Please not that this mechanism is not directly related to the file locking mechanism used by the message broker to coordinate master-slave operation, and the problem described in this article does not affect slave brokers -- it specifically affects circumstances in which multiple instances of Fuse or A-MQ start up with the same working directory, and compete for a file lock in the working directory. A slave message broker is considered to be fully started up, and is "active" for the purposes of this article.

Until Fuse 6.2.0 GA, a container that starts up as a standby exposes its SSH administration interface, just as an active container does. However, as of 6.2.0 the administration interface is not exposed in a standby container, making it rather difficult to administer. In particular, it is difficult to deploy new code on it. The problem affects use of the bin/client script as well as direct SSH connection.