Firewall settings for Bahmni (Allow only SSH, and Browser access to http, https and openerp. Block everything else). If you are using to setup on Digtial Ocean / CentOS v7.6, then scroll to bottom for comments.

setup-bahmni-firewall.sh

# Refer to this link to understand below rules: https://wiki.centos.org/HowTos/Network/IPTables

# Set default input policy to ACCEPT
iptables -P INPUT ACCEPT

# Flush all current rules!
iptables -F

# Allow localhost interface
iptables -A INPUT -i lo -j ACCEPT

# Allow Established
iptables -A INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT

# Allow SSH access
iptables -A INPUT -p tcp --dport 22 -j ACCEPT

# Allow Web Access to Bahmni Apps (http, https, openerp)
iptables -A INPUT -p tcp --dport 80 -j ACCEPT
iptables -A INPUT -p tcp --dport 443 -j ACCEPT
iptables -A INPUT -p tcp --dport 8069 -j ACCEPT


# DROP ALL Incoming connections except those which are marked as ACCEPT (Policy change!)
iptables -P INPUT DROP

# DROP all Forwards (we are not a router)
iptables -P FORWARD DROP

# Allow all output
iptables -P OUTPUT ACCEPT

# Print Final Settings
iptables -L -n -v --line-numbers

# Make changes permanent
/sbin/service iptables save

If you are using Digital Ocean cloud deployment for Bahmni, on CentOS v7, then iptables is no longer their default firewall. You can directly use Digital Ocean's network firewall option, and configure it easily from their UI. Here is a sample screenshot of how it looks when you set it up:

Configuring Firewall on Digital Ocean and applying to a droplet

Rule: Only allow for 22(ssh), 80(http), 443(https) and 8069(odoo erp) port requests from outside.

For CentOS 7.x the following script can be used to setup firewall using firewalld
firewalld configuration script

Thanks @logshvar this is helpful!