I've set up a ejabberd (v 15.04) cluster on AWS using 2 Ubuntu images. Whilst I am able to successfully cluster the two (using the command join_cluster from the 2nd node to the 1st node), I am not sure if the behavior is as expected... any thoughts would be much appreciated...
To detail the above, 2 different clients connected to the 2 nodes separately can communicate with each other. However, when I stop the server on the secondary node, I would still expect the two clients to be able to talk to each other. But instead, this 2nd client simply gets disconnected as the server is not running.
Is there something possibly that am overlooking here?
Many thanks!
join two node with join_as_master() method.
cluster code is available on github site.
for doing the Ejabberd Clustering I followed the steps from the link below :
Link : http://chadillac.tumblr.com/post/35967173942/easy-ejabberd-clustering-guide-mnesia-mysql
I hav done the Clustering with no mysql tables only mnesia database
Imp Note :
1) The ejabberd.yml file should be same as in the master host.
2) Copy the .erlang.cookies file frm the master to the slaves
3) The slave host name will be mentioned in the ejabberdctl.cfg which will different from that mentioned in yml file of the slave.
4) For my sql, as in we are creating a totally different machine ..no need to add into the cluster.
Related
Ive installed a single node greenplum db with 2 segment hosts , inside them residing 2 primary and mirror segments , and i want to configure a standby master , can anyone help me with it?
It is pretty simple.
gpinitstandby -s smdw -a
Note: If you are using one of the cloud Marketplaces that deploys Greenplum for you, the standby master runs on the first segment host. The overhead of running the standby master is pretty small so it doesn't impact performance. The cloud Marketplaces also have self-healing so if that nodes fails, it is replaced and all services are automatically restored.
As Jon said, this is fairly straightforward. Here is a link to the documentation: https://gpdb.docs.pivotal.io/5170/utility_guide/admin_utilities/gpinitstandby.html
If you have follow up questions, post them here.
i am a new user in MQTT,
and would to create a vernemq cluster of three nodes , how can i do this ? (with mosquitto client) please .
I have try to do it with the bridge in two distinct VM on ubuntu 18 but i haven't succes .
First you need to have 3 running VerneMQ nodes. Then you'll join one node to the other like this:
vmq-admin cluster join discovery-node=<OtherClusterNode>
Then you check the cluster state (you should see a 2 node cluster):
vmq-admin cluster show
Then you repeat the first command and join the 3rd node to the cluster (the discovery-node can be any node in the existing cluster).
Note: your VerneMQ nodes need to be configured correctly, namely with regard to configured listeners and ports. See here:
https://vernemq.com/docs/clustering/communication.html
If you use cloud VMs/Docker or similar, make sure you configure access accordingly.
You need to take care of a couple things if you want to run multiple VerneMQ instances on the same machine. There is a make option that let's you build multiple releases, as a commodity. This will prepare 3 correctly configured vernemq.conf files, with different ports for the MQTT listeners etc.
➜ default git:(master) ✗ make dev1 dev2 dev3
This will prepare different vernemq.conf files in the respective release builds. (look at them in the _build directory after having built the releases.)
You can then start the respective broker instances in 3 terminal windows.
Hope this helps.
EDIT: can't comment yet, so had to add this as an answer.
We are currently configuring our kafka cluster to have SSL and ACL.
Our cluster is composed of 3 nodes, and all three of them contain the same SSL/TLS(because I just copied the certificates from one node to the other two nodes) and all other kafka configurations.
Two of the nodes are successful in joining the cluster, but the last one does not.
Here is the error:
ReplicaFetcherThread
It says
UnknownTopicOrPartitionException: This server does not host this topic-partition.
I find it weird because all three of them have the same configuration.
The three servers are in Amazon EC2. They also have the same security group.
Hope you can help me understanding the problem.
This should be a comment but am still to low to comment. But you say they all have the same configuration. Did you make sure to bump the broker id on the one that's failing?
If i have three three virtual machines with cloudera hadoop single node installed, is it possible to create a cluster by connecting three of them?
like one as namenode and other two as datanodes.
I am following this documentaion...
Of course you can connect them and things should be easy once all hosts run in pseudo-distributed mode ( all the demons on the same host ).
In theory all you have to do is configuration change on all 3 hosts.
In practice you have to read also this because things are a bit different.
The first external datanode is hard work, any other will follow with no problems.
This tutorial provides exactly what you need. HTH.
I installed Datastax community version in an EC2 server and it worked fine. After that I tried to add one more server and I see two nodes in the Nodes menu but in the main dashboard I see the following error:
Error: Call to /Test_Cluster__No_AMI_Parameters/rc/dashboard_presets/ timed out.
One potential rootcause I can see is the name of the cluster? I specified something else in the cassandra.yaml but it looks like opscenter is still using the original name? Any help would be grealy appreciated.
It was because cluster name change wasn't made properly. I found it easier to change the cluster name before starting Cassandra cluster. On top of this, only one instance of opscentered needs to run in one single cluster. datastax-agent needs to be running in all nodes in the cluster but they need to point to the same opscenterd (change needs to be made at /var/lib/datastax-agent/conf/address.yaml)