Install sphinxsearch

sudo apt-get install mysql-client unixodbc libpq5
sudo dpkg -i sphinxsearch_2.1.9-release-1_amd64.deb
# or
sudo apt-get install sphinxsearch

/etc/default/sphinxsearch

sudo vim /etc/default/sphinxsearch
# set `yes` instead of 'no'

Create config file /etc/sphinxsearch/sphinx.conf

sudo vim /etc/sphinxsearch/sphinx.conf

sphinx.conf.sample

Stop, index and start sphinxsearch

sudo systemctl stop sphinxsearch.service
sudo indexer --all
sudo systemctl start sphinxsearch.service

Setup cron job to index the database at midnight

crontab -e
0 0 * * * /usr/bin/indexer --rotate --config /etc/sphinxsearch/sphinx.conf --all