How to add firewall exceptions in unix for EBS related port number

How to add firewall exceptions in unix for EBS application related ports   or any other Ports 
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Login as  root user :

Issue below commands

        iptables -I INPUT -p tcp --dport 8020 --syn -j ACCEPT

        service iptables save

        iptables -I INPUT -p tcp --dport 1541 --syn -j ACCEPT

        service iptables save

iptables -I INPUT -p tcp --dport 7021 --syn -j ACCEPT

service iptables save

Note : In the above example 8020 is my ebs port and 1541 is my database port and 7021 for                           weblogic port

iptables-save > /etc/iptables.conf

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Add the following command in /etc/rc.local to reload the rules in every reboot.

        iptables-restore < /etc/iptables.conf

File will look like below after edition : 

 cat /etc/rc.local
#!/bin/sh
#
# This script will be executed *after* all the other init scripts.
# You can put your own initialization stuff in here if you don't
# want to do the full Sys V style init stuff.

touch /var/lock/subsys/local

iptables-restore < /etc/iptables.conf

If the above line is not added you would have to issue these commands every time the server is rebooted.

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Checking Application Url is working from Unix  :

The Below Command from Unix will let you know whether the url is in accessible state or not: 

curl "http://erpprod.skydubai.com:8020/OA_HTML/AppsLogin" |head -n 1 | grep "HTTP/1.[01] [23].."

Output of command would be like below : 

  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current

                                 Dload  Upload   Total   Spent    Left  Speed

105   315    0   315    0     0   8569      0 --:--:-- --:--:-- --:--:--  8750

This curl command can be useful for troubleshooting and Daily health check or monitoring scripts to make sure you receive alerts when the application is down