Enhanced JGroups configuration
Infinispan uses JGroups as its underlying clustering layer. In order to configure the finer details of clustering (discovery, flow control, cross-site, etc) you have to provide a separate XML file with the desired configuration and reference it from your Infinispan XML file as follows:
For simple configurations this is usually fine, but configuring complex setups, such as cross-site replication, means juggling multiple files (one for the local stack, one for the cross-site stack and one for the relay configuration).
Starting with Infinispan 10 Alpha2 we have introduced a number of changes to make your life with JGroups configurations a lot easier.
Default stacks
Infinispan now comes with two pre-declared stacks: tcp and udp.
Using them is as simple as just referencing their names in the
<transport> element.
Inline stacks
Inlining a stack means you can put the JGroups configuration inside the Infinispan one as follows:
You can use the full JGroups schema, and by using XML namespaces you get full validation.
Stack inheritance
Most of the time you want to reuse one of the pre-declared stacks but
just override some of the parameters (e.g. discovery) to suit your
environment. The following example creates a new tcpgossip stack which
is based on the default tcp stack but replaces the discovery protocol
with TCPGOSSIP:
In the above example you can see that we have enhanced the JGroups
protocol declarations with two new attributes: ispn:stack.combine and
ispn:stack.position which affect how and where protocol changes are
applied on the parent configuration to obtain a new configuration.
stack.combine can be one of COMBINE (the default, possibly
overriding any specified attributes), REPLACE (which completely
replaces the protocol and resets all attributes), REMOVE (removes the
protocol) and INSERT_AFTER (which places this protocol in the stack
immediately after the protocol specified by stack.position).
Multiple stacks and Cross-site
The inline configuration really shows its usefulness in cross-site
configurations. In fact, the JGroups stack declaration has been extended
with a special element which replaces the need for a separate relay XML
file and can reference other stacks just by name. The following
configuration uses the default udp stack for the local cluster
transport and uses the default tcp stack for connecting to a remote
site:
Having the entire configuration in a single place greatly simplifies management. Of course you can combine all of the above features to obtain the configuration you need for your environment. You can find more details and examples in the documentation. Enjoy ! Tristan
Get it, Use it, Ask us!
We’re hard at work on new features, improvements and fixes, so watch this space for more announcements!Please, download and test the latest release.
The source code is hosted on GitHub. If you need to report a bug or request a new feature, look for a similar one on our JIRA issues tracker. If you don’t find any, create a new issue.
If you have questions, are experiencing a bug or want advice on using Infinispan, you can use GitHub discussions. We will do our best to answer you as soon as we can.
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Tristan Tarrant
Tristan has been leading the Infinispan Engineering Team at Red Hat for quite a while now, as well as being Principal Architect for Red Hat Data Grid. He's been a passionate open-source advocate and contributor for over three decades.
