I want to run repair/compact operation from 1 Cassandra cluster node instead of scheduling it from all nodes in a cluster.
I am using cassandra 3 version.
"nodetool -h **NODEIP** repair keyspace" is not working if I specify other node in the cluster. This command only works for the local node which I run this command. Please suggest a way to run repair/compaction for all nodes by running from one node in a cluster.
Thanks
By default JMX security is disabled and accessible only from localhost, as nodetool uses JMX to communicate with Cassandra, nodetool will only work on the local node unless JMX security is enabled.
See this Datastax page on how to enable JMX authentication.
Related
Whenever I am restarting my any Cassandra node in my cluster after few minutes other nodes are showing down, sometimes other nodes also hanging. We need to restart other nodes to up the services.
During restart cluster seems unstable and one after other showing stress and DN status however JVM and nodetool services are running fine but when we are describing the cluster it is showing unreachable.
We don't have much traffic and load in our environment. Can you please give me any suggestion.
Cassandra version is 3.11.2
Do you see any error/warning in your system.log after the restart of the node?
I am about to use simple cassnadra cluster (3 nodes, x.x.x.104-106). I'm using CentOS7, so i used datastax repository, Cassandra 3.0.
I read on forum, it is better to install the cassandra-stress outside the cluster, otherwise it consumes CPU of the node.
Could you please help me, how to install it?
I tried to copied cassandra-stress.sh separately, but it is dependent on some cassandra files (probably created during installation).
So I decided to install whole Cassandra on separate server, in the same network space. Now, I'm struggling with the correct setup, how to run cassandra-stress tool against the cassandra cluster.
In cassandra.yaml I setup Cassandra name, listen_adress to public_ip, rpc_address to loopback address, I set seeds to cassandra cluster nodes (x.x.x.104-106)... but in general it does not make sense to set it up, since I dont wan't create another node in the Cassandra cluster.
Could you please help me?
Edit: Maybe using something like this might be the correct way?
cassandra-stress user profile=/usr/cassandra/stress-file.yaml ops(insert=1,books=1) n=10000 -node x.x.x.104,x.x.x.105,x.x.x.106 -port native= ?
Telnet [cassandra_node_ip_ddress] 7000 works fine
If you have your Cassandra cluster running with the proper ports open (by default 9042 for clients and 7199 for JMX), and Cassandra directory on a different machine, then you should be able to run cassandra-stress, from outside the cluster, against your cluster simply by passing the -node option with an IP of one of the nodes in your cluster (say x.x.x.104). For example,
$CASSANDRA_HOME/tools/bin/cassandra-stress write -node x.x.x.104
should work. You can see more options with
$CASSANDRA_HOME/tools/bin/cassandra-stress help
on every node:
in cassandra.yaml set rpc_address to IP address
in cassanda-env.sh set LOCAL_JMX=no and jmx options autenticate=false
open firewall port 7199
restart firewall and cassandra
on cassandra-stress server:
cassandra-stress user profile=/usr/cassandra/stress-books.yaml ops\
(insert=1,books=1\)
n=10000 -node 172.16.20.104,172.16.20.105,172.16.20.106 -port native=9042
thrift=9160 jmx=7199
Note! JMX communication is not secured
In other dbs, we connect to db cluster with load balance IP. How do we connect to cassandra cluster using command line? What socket is used? Is this always a single node and IP?
What if i connect o node1, and node1 goes down. Will this automatically connect to node2 or node3?
You have several options: the easiest one is to use the Cassandra Query Language Shell (CQLSH), which is a python based CQL interpreter to interact with Cassandra. It usually comes with every Cassandra installation, under the /bin folder of the installation directory. If you have ssh access to one of the nodes Cassandra is running onto, this can be an easy option (you will avoid any issues related to firewall blocking incoming connections to your cluster).
You can also use cqlsh to access remotely to the cluster:
cqlsh node_ip 9043
but this will require cqlsh to be present on your machine.
In general, Cassandra uses an initial set of contact nodes and a gossip protocol to contact and learn the cluster composition. You will be assigned a node as coordinator for your query. You may not worry about seed nodes being currently down, provided that at least one is up and running.
Another option to access remotely to the cluster is the Datastax DevCenter,which is a free-to-use grafical interface to execute CQL queries.
Hope this helps
I had setup a 50 node Apache Cassandra cluster
I took one node and wanted to install DSE on it and make is a single node DSE cluster
I have removed /var/lib/cassandra and /var/log/cassandra
I have truncated systems.peers table on the single node
When I start dse cassandra on this node, I still see the remaining nodes doing handshake and being added to this cluster.
What is the best way to complete remove any traces of existing Cassandra cluster from this node?
You need to change the cluster_name directive in cassandra.yaml to a different name to the rest of the cluster.
I just installed a 3 node cassandra (2.0.11) community cluster with a single seed node. I installed opscenter (5.0.2) on the seed node and everything is working fairly well. The only issue I am having is that any node actions I perform (stop, start, compact, etc) apply only to the seed node. Even if I choose a different node on the ring or list, the action always happens on the seed node.
I watched the opscenter logs and can see requests for /ops/compact/ip_address and the ip address is the correct node that I chose but the action always run on the seed instance.
All agents have been installed on all the nodes and the cluster is fully operational. I can run nodetool compact on each node and see the compaction progress in opscenter.
I have each node configured to listen on an internal address and have verified that the rpc server is open on the network. I have also tried adding the cluster using a non-seed node but all actions continue to run on the seed node.
Posted the answer above but I'll explain more in detail for anyone else with this issue.
I changed rpc_address and listen_address in cassandra.yaml in order to listen on a private ip address. I restarted cassandra and the cluster could communicate easily. The datastax-agent was still reporting 127.0.0.1 to opscenter as the rpc address. I found this out by enabling trace logging in opscenter.
If you modify anything in cassandra.yaml, make sure you restart the datastax-agent as it apparently caches the data.