Developing iRules for BIG-IP

This course is intended for system administrators, network administrators and application developers responsible for the customization of traffic flow through a BIG-IP system using iRules.

Topics Covered

• Setting up the BIG-IP system
• Getting started with iRules
• Leveraging DevCentral resources for iRule development
• Exploring iRule elements, including events, functions, commands, variables, and operators
• Using control structures for conditional branching and looping
• Mastering whitespace, grouping, and special symbols
• Measuring iRule efficiency using timing statistics
• Logging from an iRule using syslog-ng and high-speed logging (HSL)
• 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)
• Working with strings, including using Tcl parsing commands and iRules parsing functions
• Accessing and manipulating HTTP traffic, including applying selective HTTP compression
• Working with iFiles and data groups
• Using iRules with universal persistence and stream profiles
• Gathering statistics using STATS and ISTATS
• Incorporating advanced variables, including arrays, static variables, and the session table

At the end of this course, the student will be able to:

• Describe the role of iRules in customizing application delivery on a BIG-IP system
• Describe best practices for using iRules
• Define event context, and differentiate between client-side and server-side contexts, request and response contexts, and local and remote contexts
• Trigger an iRule for both client-side and server-side request and response events
• Assign multiple iRules to a virtual server and control the order in which duplicate events trigger
• Describe and use a testing methodology for iRule development and troubleshooting
• Use local variables, static variables, lists, arrays, the session table, and data groups to store information needed for iRule execution
• Write iRules that are optimized for runtime and administrative efficiency
• Use control structures to conditionally branch or loop within an iRule
• Log from an iRule using Linux syslog-ng or TMOS high-speed logging (HSL)
• Incorporate coding best practices during iRule development
• Use analyzer tools to capture and view traffic flow on both client-side and server-side contexts
• Collect and use timing statistics to measure iRule runtime efficiency
• Write iRules to help mitigate and defend from some common HTTP attacks
• Differentiate between decimal, octal, hexadecimal, floating-point, and exponential notation
• Parse and manipulate strings using Tcl commands and iRule functions
• Write iRules to access and manipulate HTTP header information
• Write iRules to collect customized statistics
• Implement universal persistence via an iRule
• Modify payload content using an iRule with a stream profile

The following free web-based courses, although optional, will be very helpful for any student with limited BIG-IP administration and configuration experience.

These courses are available at LearnF5 (https://www.f5.com/services/training):

• Getting Started with BIG-IP
• Getting Started with BIG-IP Local Traffic Manager (LTM)

The following general network technology knowledge and experience are recommended before attending any F5 Global Training Services instructor-led course:

• OSI model encapsulation
• Routing and switching
• Ethernet and ARP
•  TCP/IP concepts
• IP addressing and subnetting
• NAT and private IP addressing
• Default gateway
• Network firewalls
• LAN vs. WAN

The following course-specific knowledge and experience is suggested before attending this course:

• HTTP protocol
• Any programming language