What is iRule in F5?
Andrew Henderson
Updated on March 01, 2026
What is iRule in F5?
An iRule is a script that you write if you want to make use of some of the extended capabilities of the BIG-IP that are unavailable via the CLI or GUI. iRules allow you to more directly interact with the traffic passing through the device.
How do you make an iRule in F5?
How to create the iRule
- On the Main tab, click Local Traffic > iRules.
- Click Create.
- In the Name field, type a name, such as my_irule. The full pathname of the iRule cannot exceed 255 characters.
- Click Finished.
What are 3 key elements of iRule in F5?
Basic iRule elements¶
- Event declarations.
- Operators.
- iRule commands.
What is iRule in networking?
An iRule basically is a script that executes against network traffic passing through an F5 appliance. iRules can route, re-route, redirect, inspect, modify, delay, discard or reject, log or … do just about anything else with network traffic passing through a BIG-IP.
What is the function of iRule?
An iRule is a powerful and flexible feature of BIG-IP devices based on F5’s exclusive TMOS architecture. iRules provide you with unprecedented control to directly manipulate and manage any IP application traffic.
What is iRule in load balancer?
What is SSL offloading in F5?
SSL offloading means that all HTTPS traffic is decrypted on the Load Balancer and passed to the backend servers in plain HTTP. When information is transmitted through SSL secure protocol, the webserver acts to encrypt or decrypt your web traffic.
What is F5 DevCentral?
DevCentral: An F5 Technical Community. Application DeliveryCloudDevOpsSecurity. Security.
What is F5 engineer?
An F5 Engineer is what people usually refers to the Network Engineer or Consultant working with products from F5 Networks. The main focus of F5 Networks is Application Delivery Networking (ADN) that optimises delivery of network-based applications.
What does iRule stand for?
iRules can route, re-route, redirect, inspect, modify, delay, discard or reject, log or … do just about anything else with network traffic passing through a BIG-IP. The idea behind iRules is to make the BIG-IP nearly infinitely flexible.
What is iApp in F5?
What is F5 iApp? F5 iApp™ is a powerful new set of features in the BIG-IP system that provides a new way to architect application delivery in the data center, and it includes a holistic, application-centric view of how applications are managed and delivered inside, outside, and beyond the data center.
Why choose F5 irules?
Aside from making decisions based on header data, iRules even allow us to make traffic decisions on any type of payload content / data you define. Our F5 iRule Consulting – Development & Support process sets us apart from the competition.
What is the irules feature?
The iRulesTM feature not only allows you to select pools based on header data, but also allows you to direct traffic by searching on any type of content data that you define. Thus, the iRules feature significantly enhances your ability to customize your content switching to suit your exact needs.
How can I improve the performance of my irules?
Optimizing iRules execution, including implementing efficiency best practices Modularizing iRules for administrative efficiency, including using procedures Securing web applications with iRules, including preventing common HTTP attacks, securing HTTP headers and cookies, and implementing HTTP strict transport security (HSTS)
What should I know before attending the developing irules for BIG-IP course?
The following course-specific knowledge and experience is suggested before attending this course: The Developing iRules for BIG-IP v15.1 course presents much of the same content as v14.1, with very minor modifications. Passwords are 8 digits in length i.e.. f5trn0XX.