cassandra_config_notes.md

Notes on configuring apache cassandra

AW2018-02-21

Cassandra Install

Install instructions at http://cassandra.apache.org/download/

echo "deb http://www.apache.org/dist/cassandra/debian 311x main" | sudo tee -a /etc/apt/sources.list.d/cassandra.sources.list
curl https://www.apache.org/dist/cassandra/KEYS | sudo apt-key add -

For Trusty (Ubuntu 14.04LTS) we need java-8 from an external PPA.

sudo add-apt-repository ppa:webupd8team/java -y
sudo apt-get update
sudo apt-get install oracle-java8-installer
sudo apt-get install oracle-java8-set-default

now we can install cassandra

sudo apt install cassandra cassandra-tools

and we should have:

$ java -version
openjdk version "1.8.0_151"
$ python --version
Python 2.7.12
$ cassandra -v
3.11.2

As of 2018-08 there is an update and we get

$ cassandra -v
3.11.3

Config

SSL keys

Following https://docs.datastax.com/en/cassandra/latest/cassandra/configuration/secureSSLNodeToNode.html

Configure

cassandra.yaml

cluster_name: 'my cluster'
seed <seed_ip>
listen_address: <my_ip>
rpc_address: 0.0.0.0
broadcast_rpc_address: <my_ip>
endpoint_snitch: GossipingPropertyFileSnitch

To enalbe SSL encryption between nodes, using the keys we created previously

server_encryption_options:
    internode_encryption: all
    keystore: /etc/cassandra/192.168.7.2.jks
    keystore_password: myKeyPass
    truststore: /etc/cassandra/server-truststore.jks
    truststore_password: truststorePass

cassandra-env-sh

JVM_OPTS="$JVM_OPTS -Djava.rmi.server.hostname=127.0.0.1"

after config-changes we need:

$ sudo systemctl stop cassandra.service
$ sudo rm -rf /var/lib/cassandra/data/system/*
$ sudo systemctl start cassandra.service

rackdc.properties

multiple datacenters require special configs - so it's simpler to have all machines in DC1.

dc=DC1
rack=RAC3

topology.properties

Do we need this? Probably not if rackdc.properties is set and we use GossipingPropertyFileSnitch.

ip1=DC1:rac1
ip2=DC1:rac2

test

$ nodetool status
Datacenter: datacenter1
=======================
Status=Up/Down
|/ State=Normal/Leaving/Joining/Moving
--  Address    Load       Tokens       Owns (effective)  Host ID                               Rack
UN  127.0.0.1  79.03 KiB  256          100.0%            353d1b04-955d-4929-b536-ffde8fd3a80e  rack1

$ cqlsh
Connected to my cluster at 127.0.0.1:9042.
[cqlsh 5.0.1 | Cassandra 3.11.2 | CQL spec 3.4.4 | Native protocol v4]
Use HELP for help.
cqlsh> 

Python cassandra-driver

installing cassandra-driver takes a long time..

sudo apt-get install libev4 libev-dev
sudo pip install cassandra-driver

python test program

from cassandra.cluster import Cluster

c = Cluster(["127.0.0.1", "192.168.7.1", "192.168.7.2"])
s = c.connect()

s.execute("use test1_keyspace")
r = s.execute("select * from person")

for p in r:
	print p

c.shutdown()