We're attempting to add standalone zookeeper servers into the zk ensemble ran by fuse fabric (as either followers or observers). However, it looks like fabric has pretty tight control over the zk configuration and I haven't been able to find any documentation relating to adding hardcoded server configuration params to the dynamic ones used by fabric. Anyone else try this or have some idea of where to look?
Related
I'm using payara 5.201. I have two instances running in docker in the same network. Payara uses eclipselink 2.7.4.
I used the settings as described here.
I enabled and started the hazelcast grid in both payara instances.
I created a rest resource which can get and update data in an entity.
When I set some value in instance one I expect the get on instance two to show the same information but it doesn't.
What am I doing wrong?
See here for a test project that you can run/debug.
The problem is fixed, the issue was that the hazelcast discovery mode is 'domain' by default in payara server (it is multicast in payara-micro) which makes sense because usually a payara cluster is used.
But in my case there is no cluster but simply two payara (DAS) instances. So setting the hazelcast cluster mode to multicast solved the problem.
This works in this case because both docker instances are started using docker-compose and share the same network so multicast works.
I updated the github repo. Check it out.
I'm a bit confused with this configuration. My Spring Boot app with #EnableDiscoveryClient has spring.cloud.consul.host set to localhost. I'm running a Consul Agent on the host where my Boot app is running, but I've a few questions (can't seem to find my answers in the documentation).
Can this config accept multiple values?
If so, I'd prefer to set the values to a list of Consul server addresses (but then, what's the point of running Consul Agents at all, so this doesn't seem practical, which means I'm not understanding something here)
If not, are we expected to run a Consul Agent on every node a Boot app with #EnableDiscoveryClient is running? (this feels wrong as well; for one, this would seem like a single point of failure even though one agent should be able to tell everything about the cluster; what if I can't contact this one agent?)
What's the best practice for this configuration?
Actuallly this is Consul itself to solve your problem. An agent is runing on every server to handle clustering, failures, sharing data, autodiscovery etc. for you so that you don't neen to know the other hosts in your Spring Boot configuration. Spring Boot app always connects to the agent running on the same machine.
See https://www.consul.io/docs/agent/basics.html
Got a general question about load balancing setup in JBoss (7.1.1.Final). I'm trying to setup a clustered JBoss instance with a master and slave node and I'm using the demo app here (https://docs.jboss.org/author/display/AS72/AS7+Cluster+Howto) to prove the load balancing/session replication. I've basically followed through to just before the 'cluster configuration' section.
I've got the app deployed to the master and slave nodes and if I hit their individual IPs directly I can access the application fine. According to the JBoss logs and admin console the slave has successfully connected to the master. However, if I put something in the session on the slave, take the slave offline, the master cannot read the item that the slave put in the session.
This is where I need some help with the general setup. Do I have to have a separate apache httpd instance sat in front of JBoss to do the load balancing? I thought there was a load balancing capability built into JBoss that wouldn't need the separate server, or am I just completely wrong? If I don't need apache, please could you point me in the direction of instructions to setup the JBoss load balancing?
Thanks.
Yes, you need a Apache or any other software or hardware that allows you to perform load balancing of the HTTP request JBoss Application Server does not provide this functionality.
For proper operation of the session replication you should check that the server configuration and the application configuration is well defined.
On the server must have the cache enabled for session replication (you can use standalone-ha.xml or standalone-full-ha.xml file for initial config).
To configuring the application to replicate the HTTP session is done by adding the <distributable/> element to the web.xml.
You can see a full example in http://blog.akquinet.de/2012/06/21/clustering-in-jboss-as7eap-6/
So I am a little confused by reading the documents.
I want to setup AppFabric caching and hosting.
Can I do the following?
DC
SQL Server
AppFabric1
AppFabric2
All these computers are joined to the DC.
I want to be able to have AppFabric1 be the mainhost but also part of the cache cluster?
What about AppFabric2? or AppFabricX? How can I make them part of the cache cluster?
Do I have to make AppFabric1 and AppFabric2 configured in Windows as part of a cluster (i.e setup the entire environment as a cluster)?
Can I install AppFabric independently on AppFabric1 and 2 and have them cluster together and "make it work"? If so - how?
I see documentation about setting it up in a webfarm but also a workgroup... and that's it. nothing about computers joined to a domain.
I want to setup AppFabric caching and hosting.
Caching and Hosting are two totaly different things and generally don't share the same use cases.
AppFabric Caching provides an in-memory, distributed cache platform for Windows Server, previously named Velocity. The cache cluster is a collection of one or more instances of the Caching Service working together. You can easily add new cache host without restarting the cluster in the "storage location" (xml or sql server).
Can I install AppFabric independently on AppFabric1 and 2 and have
them cluster together and "make it work"? If so - how?
Don't worry... this can be done easily during installation. In addition, there are powerfull PS module to to the same thing.
AppFabric Hosting enhance the hosting of WCF and Workflow Foundation services in WAS (autostart, monitoring of hosted services, workflow persistence, ...). There is no cluster here and basically you just have to configure to monitoring/persistence DB for each server.
Just try it !
When you are adding the second node in the AppFabric cluster, make sure to choose the option Join Cluster (instead of New Cluster) and point to the path of the share where you stored the configuration (assuming that you used FILE SHARE to store the configuration of the cluster). The share that you used should be accessible from Appfabric2.
I have 2 instances of Jboss servers running on eg: 127.0.0.1 and 127.0.0.2.
I have implemented Jboss load balancing, but am not sure how to achieve server failover. I do not have a webserver to monitor the heartbeat and hence using mod_cluster is out the question. Is there any way I can achieve failover using only the two available servers?
Any help would be appreciated. Thanks.
JBoss clustering automatically provides JNDI and EJB failover and also HTTP session replication.
If your JBoss AS nodes are in a cluster then the failover should just work.
The Documentation refers to an older version of JBoss (5.1) but it has clear descriptions of how JBoss clustering works.
You could spun up another instance to server as your domain controller, and the two instances you already have will be your hosts. Then you could go through the domain controller, and it will do the work for you. However, I haven't seen instances going down to often, it usually servers that do, and it looks like you are using just one server (i might be wrong) for both instances, so i would consider splitting it up.