Install Cassandra v.1.2 on OSX

cassandra12.sh

# Install Cassandra version 1.2.9
mkdir ~/tmp
cd ~/tmp
curl -O http://archive.apache.org/dist/cassandra/1.2.9/apache-cassandra-1.2.9-bin.tar.gz
tar -xzf apache-cassandra-*
rm -rf *.tar.gz

# Create cassandra lib/log directory and grant access to it?
sudo mkdir /var/lib/cassandra
sudo mkdir /var/log/cassandra

# Move cassandra into own dir
mv apache-cassandra-* ~/cassandra

# Add config to your .zshrc / .bashrc
export CASSANDRA_HOME=~/cassandra # Add Cassandra 1.2 config
export PATH="$PATH:$CASSANDRA_HOME/bin"

To start Cassandra:

# Start Cassandra in foreground
cassandra

# Start Cassandra CLI
cqlsh