Cannot connect to my Cassandra with localhost - cassandra

Question

My Cassandra used to work with no problems.
I was able to connect with no problems but now for some reason it doesn't work anymore.
[default#unknown] connect localhost/9160;
Exception connecting to localhost/9160. Reason: Connection refused.
I am in Ubuntu server
Thanks in-advance

Answer 1

The solution to this question was provided to you on the pycassa google group:
https://groups.google.com/d/topic/pycassa-discuss/Bai7bvkHYU4/discussion
This is not a pycassa problem. The problems you are having are specific to starting a Cassandra instance and not following the documentation in the README.txt that is in the root folder of the distribution:
Getting started
This short guide will walk you through getting a basic one node cluster up
and running, and demonstrate some simple reads and writes.
tar -zxvf apache-cassandra-$VERSION.tar.gz
cd apache-cassandra-$VERSION
sudo mkdir -p /var/log/cassandra
sudo chown -R whoami /var/log/cassandra
sudo mkdir -p /var/lib/cassandra
sudo chown -R whoami /var/lib/cassandra
Note: The sample configuration files in conf/ determine the file-system
locations Cassandra uses for logging and data storage. You are free to
change these to suit your own environment and adjust the path names
used here accordingly.
Now that we're ready, let's start it up!
bin/cassandra -f
Running the startup script with the -f argument will cause Cassandra to
remain in the foreground and log to standard out.
Now let's try to read and write some data using the command line client.
bin/cassandra-cli --host localhost
The command line client is interactive so if everything worked you should
be sitting in front of a prompt...
Connected to: "Test Cluster" on localhost/9160
Welcome to cassandra CLI.
Type 'help;' or '?' for help. Type 'quit;' or 'exit;' to quit.
[default#unknown]
As the banner says, you can use 'help;' or '?' to see what the CLI has to
offer, and 'quit;' or 'exit;' when you've had enough fun.

Answer 2

Verify the following:
Cassandra process is running and thrift is listening on 9160 (netstat-tulpn)
9160 port not being blocked by a firewall rule or similar
If the above are true, then check the cassandra log for additional information.
Other than that your description is pretty vague. So any other information about what may have changed in the environment would be helpful.

Answer 3

I faced the same problem and the reason was that I had configured Cassandra to listen on the Server IP and not on localhost.
/etc/dse/cassandra/cassandra.yaml
listen_address: 10.102.8.71
So try this and check if it works for you:
cassandra-cli --host "your host name"