nodejs - cassandra-client error: All connections are unhealthy - node.js

Question

I keep getting this error when I try to retrieve/update data from cassandra using cassandra-client.
{ [Error: All connections are unhealthy.]
connectionInfo:
{ host: 'localhost',
port: 9160,
keyspace: 'keyspace1',
user: undefined,
pass: undefined,
use_bigints: false,
timeout: 4000,
log_time: false,
staleThreshold: 10000 } }
Haven't got a clue as to what this error means.

Answer 1

The error indicates that your client is not able to connect to the specified server on localhost port 9160.
Since this is localhost you can most likely exclude any firewall problems.
What you can do
1. Check if your server is running after all
This should show you one or more processes ( except the grep process you're just executing
ps aux | grep "cassandra"
2. Verify the port
# telnet localhost 9160
Trying 127.0.0.1...
telnet: connect to address 127.0.0.1: Connection refused
Bad.. This would indicate that something with your configuration might be wrong. In my case I simply don't have a cassandra server listening to port 9160 ( running at all )
3. Check your logfile
By default casandra writes into the folder /var/log/cassandra/
If anything is wrong with the server, you'll most likely have some more information available in there, might even show a problem related to your nodejs client
4. Try another client for debugging
http://wiki.apache.org/cassandra/GettingStarted#Step_4:_Using_cassandra-cli