Hello group members.
I'm having problems with clustering/federating an application's Artemis
embedded server.
The application is a .WAR with Springframework 4 and Embedded Artemis
1.1.0 (from Spring).
Multiple instances of the application are expected to be deployed in
multiple spots. The Artemis component is expected to cluster a JMS Topic
between nodes so that if any node sends a message on the topic all
listeners on all nodes should receive the message.
With a few problems I was able to make the Embedded Artemis Server handle
topic in a single deployment.
Every application connects to the Embedded Artemis using InVM connector.
Trying to cluster instances does not work!
My configuration contains:
- A NettyAcceptor on (host):(random-high-port)
- A NettyConnector on (host):(random-high-port) named "cluster-connector"
- A BroadcastGroupConfiguration named "cluster-broadcast"
= UDPBroadcastEndpointFactory
* group-host 239.1.2.3
* group-port 12345
* local-host (host)
* local-port (random-high-port)
= ConnectorInfos
* "cluster-connector"
- DiscoveryGroupConfiguration named "cluster-discovery"
= UDPBroadcastEndpointFactory
* group-host 239.1.2.3
* group-port 12345
* local-host (host)
* local-port (random-high-port)
- ClusterConnectionConfiguration named "cluster"
= address: "cluster-address"
= connectorName: "cluster-connector"
= discoveryGroupName: "cluster-discovery"
The configuration is done in Java (not XML) via
o.a.a.a.core.config.Configuration
As already noted this does not work, even worse when a second application
instance is brought up the VMs on both instances hang on attempt to
shut-down.
I noticed a possible problem: the network monitor showed, that the
applications keep open UDP socket that has a Send-Q that continuously grows
until about 200K pending, and then it seizes. Further using a tcpdump I
noticed, that the packages being sent by Artemis look invalid, as they're
really BIG: 4096 bytes broadcast datagrams!
Looking further I found out a possible BUG in
…cluster.impl.BroadcastGroupImpl in the broadcastConnectors() method. It
seems the method works incorrectly with the ActiveMQBuffer and the
underlying NIO ByteBuffer, and instead of sending a package with the needed
data it sends the whole Buffer of nearly 4K zeros and only a few hundred
bytes of actual payload. A package of 4K is next to impossible to send as a
datagram packet.
I've tried to perform a hot-fix for this issue and succeeded (the
datagrams fell to about 250 bytes), datagrams are sent and received, but
the cluster still does not form.
Please advise!
Is there a way to create a cluster without using discovery? Assuming I
know every instance of the application at initialisation time is it
possible to create a cluster of pre-defined nodes?
Hope I get help.
