DataStax Devcenter fails to connect to the remote cassandra database

Question

OS: CentOS 6.4 (server)

I have successfully installed (yum install dsc20) the cassandra database layer in my server and can connect to it using the CQL SHel (cqlsh).

Answer 1

If there's somebody working with docker locally, it can run this command.

docker run --name cassandra -p 127.0.0.1:9042:9042 -p 127.0.0.1:9160:9160 
-e CASSANDRA_LISTEN_ADDRESS=localhost 
-e CASSANDRA_BROADCAST_ADDRESS=localhost
-e CASSANDRA_RPC_ADDRESS=localhost -d cassandra

Answer 2

DataStax DevCenter being built on top of the DataStax Java driver has the same connectivity requirements as the driver. Namely:

1. start_native_transport: true
2. rpc_address: IP or hostname reachable from the client
3. Machines in the cluster accept connections on port 9042 (the native_transport_port config option)

If rpc_address is set to either a private IP or to 0.0.0.0, DevCenter will not know what node to connect to.

If your cluster has multiple nodes and these are using rpc_address: 0.0.0.0, even if you configure DevCenter with the IP(s) of a couple of nodes, it will still have issues discovering the other nodes in the cluster.

In cassandra.yaml there's a comment/warning about using rpc_address: 0.0.0.0:

Note that unlike ListenAddress above, it is allowed to specify 0.0.0.0 here if you want to listen on all interfaces, but that will break clients that rely on node auto-discovery.

Note: it is possible that in the future DevCenter might be able to ignore/filter out nodes in the cluster configured with rpc_address: 0.0.0.0.

Answer 3

Try this.. It worked for me!

Run the following command on your machine where you have DevCenter installed

$> ssh -L 9042:localhost:9042 <username>@<ip-address-cassandra-db> -N

After running this command, it will prompt for password

Now in your DevCenter > Contact Hosts, provide "127.0.0.1" and test connection. Bingo, you see the magic...

Answer 4

In the cassandra.yaml, I set

1. listen_address: localhost
2. rpc_address: 1.2.3.4
3. broadcast_rpc_address: 1.2.3.4

After doing a

sudo service cassandra restart

DevCenter was able to successfully connect.

After this change, cqlsh would not start without the address:

cqlsh 1.2.3.4

You can set the environment variable $CQLSH_HOST=1.2.3.4. Then simply type cqlsh.