devnotes.txt

For node reverse proxy:

<Directory />
Options -Indexes +FollowSymLinks
AllowOverride None
Require all granted
</Directory>

ProxyPreserveHost On
ProxyVia Full
<Proxy *>
  Require all granted
</Proxy>

ProxyPass / http://127.0.0.1:3100/
ProxyPassReverse / http://127.0.0.1:3100/

Use pm2 for node process service management.
sudo pm2 restart server
sudo pm2 status

rs-engine on localhost:3200
use /var/www/rs-engine/ecosystem.config.js
pm2 start ecosystem.config.js

for apache changes
sudo systemctl restart apache2
sudo systemctl status apache2

cd /etc/apache2/sites-available
sudo nano mysite
sudo a2ensite mysite
sudo a2dissite 000-default.conf
sudo apache2ctl configtest
sudo systemctl restart apache2


--

elasticsearch:
-------------
curl -fsSL https://artifacts.elastic.co/GPG-KEY-elasticsearch | sudo apt-key add -

echo "deb https://artifacts.elastic.co/packages/7.x/apt stable main" | sudo tee -a /etc/apt/sources.list.d/elastic-7.x.list

sudo apt update

sudo apt install elasticsearch

sudo nano /etc/elasticsearch/elasticsearch.yml
edit, add final line
network.host: localhost

sudo systemctl start elasticsearch
-- if times out, ensure you have swap space set up

sudo systemctl enable elasticsearch

-- test elasticsearch
curl -X GET 'http://localhost:9200'