Cassandra upgrade rollback sample script

cassandra_rollback.sh

#!/bin/bash
set -e #fail on error

function log {
    echo "[`date`] $@"
}

log "Rolling back cassandra. Press <ENTER> to continue.."
read

log "Stopping new cassandra version.."
/bin/ps -ef | /bin/grep -E "javaagent.*cassandra" | /bin/grep -v grep | /usr/bin/awk '{print $2}' | /usr/bin/xargs kill -9
sleep 2

DATA_DIR=/mnt/cassandra/data
OLD_DATA_DIR=/mnt/cassandra/data.old

for ks in `ls $DATA_DIR`; do
    for cf in `ls $DATA_DIR/$ks`; do
        log "Cleaning $ks/$cf"
        mkdir -p $OLD_DATA_DIR/$ks/$cf
        for file in `find $DATA_DIR/$ks/$cf -type f  | grep -i -v snapshot | grep -v -i backup`; do
            mv $file $OLD_DATA_DIR/$ks/$cf
        done

        log "Recovering $ks/$cf"
        if [[ -d $DATA_DIR/$ks/$cf/snapshots/backup ]]; then
            rsync -avhW --no-compress --progress $DATA_DIR/$ks/$cf/snapshots/backup/ $DATA_DIR/$ks/$cf;
        fi
    done
done

log "Starting old cassandra version.."
/opt/cassandra/bin/cassandra