Data migration for RDS to Redshift

Configure ec2 instance for migration

• Launch an instance with sufficient memory and cpu (160G SSD disk, and c3.large), set up with the right security configuration

• Install these on the instance:

sudo apt-get update
sudo apt-get install awscli
sudo apt-get install postgresql-client-common
sudo apt-get install postgresql-client
sudo apt-get install pigz
sudo apt-get install htop
sudo apt-get install python-pip
sudo pip install boto

• Run aws configure to set up your AWS keys

• Setup the following env parameters (used by different modules):

export AWS_ACCESS_KEY_ID=<ke>
export AWS_SECRET_ACCESS_KEY=<secret>
export aws_access_key_id=<key>
export aws_secret_access_key=<secret>
unset PGPASSWORD

• Create ~/.pgpass for psql to run from bash. On each for RDS replica, and Redshift cluster with the following format: hostname:port:database:user:password

• chmod 600 ~/.pgpass

• Create a directory named Copy to the bash script for copying data from S3 to Redshift

• Copy these scripts into the home directory

upload.py
get_data.sh
get_count.sh

To run the migration

The script is set up to import daily tables from device_sensor and tracker_motion.

python upload.py [table-name-prefix] [YYYY] [MM] [DD] [download_data] [split_data]

• download_data ('yes'/'no'): input 'yes' if you want to download the data directly from RDS, or 'no' if you already have a copy
• split_data ('yes'/'no'): input 'yes' if you want to split the data into smaller chunks, highly recommended

Example

To migrate device_sensor for 2015-08-12:

python upload.py device_sensors_par 2015 08 12 yes yes > migrate_2015_08_12.log 2>&1

The sequence of events:

• a directory device_sensors_par_2015_08_12 will be created
• a csv file of the daily table will be downloaded, named device_sensors_par_2015_08_12.csv
• the csv file will be split into files of 1000000 lines each, with names starting from device_sensors_par_2015_08_12-00000
• all data files will be gzipped and uploaded to and S3 bucket [main-bucket]/device_sensors_2015_08/2015_08_12/
• a manifest file will be created and also uploaded to the same S3 bucket
• you will find copy_device_sensors_par_2015_08_12.sh in the Copy directory with the command to upload data to Redshift.