F5 System Engineer LTM Certified

Yesterday I passed the second and final exam in the F5 System Engineering track F50-522. Without breaking NDA lets go into an overview of the exam :
- As I mentioned in LTM Essentials F50-521 exam, the questions are mostly based on theory. So you need to know hot things works instead of how things are done. Having more then 3 years of hands on with those devices, I really had hard time on some of the questions :)
- Majority of the questions requires you to have a deep understanding of Virtual Server types (network,transparent,forwarding), SNAT/NAT concepts like automap and how source and destination IP@ changes from client to member node.
- Master the iRules. Know the context for each method. Know how context changes the behavior of local_address/remote_address etc..
- Master TCL functions like findstr,starts_with,ends_with etc..
- Know variety of logging options like alertd,syslog-ng and snmpd
- And for sure you need to have a good understanding of how HTTP works. Cookies, Keep-alive messages and their interaction with One-Connect profiles, XForward headers etc..

F5 BigIP Virtual Edition

F5 released a trial version of their famous LTM (Local Traffic Manager) product. The product is valid for 90 days trial use. It can be a great candidate for testing the product for your virtual environment or building a home lab for your F5 Certification studies.(F50-521 and F50-522 exams)

First download the file for your VMware virtual platform (ESX(i) vSphere or Workstation 7)

https://downloads.f5.com/esd/product.jsp?sw=BIG-IP&pro=big-ip_ve&prodesc=BIG-IP+Virtual+Edition

Then generate a registration key for your product that will be used to create the dossier file for activation during initial setup. You can have up to 4 registration keys e-mailed to you :

https://www.f5.com/trial/secure/generate-eval-key.php

The virtual machine has :

1 GB RAM
3 NIC (should be possible to additional NIC for redundant pair heartbeat traffic)
10 GB vdisk

NOTE : Don't try to decrease memory, otherwise you will have problems allocating additional modules to LTM.

You can find the detailed installation document on :
https://support.f5.com/kb/en-us/products/big-ip_ve/releasenotes/product/relnotes_ve_10_1_0.html

F5 Big IP LTM Certification

I've been planning to have F5 certification for a long time. Last Tuesday I had a chance to take and pass the fist exam of F5 System Engineering track which is the F50-521 LTM essentials exam. That makes me certified as F5 Product Consultant - Local Traffic Management. 10th IT certification in my museum :)

 As part of NDA I will not go into the details but will give an overview of the exam :

- First of all Student/Instructor guide is not alone sufficient for the exam. You should also take a look on product documentation. The exam is currently covering 9.4 material.
- Apart from the practical side of the devices, you should mostly focus on the theory. I didn't get any lab question like I had in Cisco exams.
- Knowing the theory of NAT/SNAT, iRule, some of the TCL function syntax, VS, Pool and Profile details, redundancy/failover concepts will help you a lot in the exam.
- You will need 76% to pass out of 50 questions. If all questions have the same weight that means you have a chance to make 12 mistakes.

Next week I will also take the F50-522 Advanced exam for the F5 System Engineer certification. Good luck to me ;-)

NOTE : I'm still preparing for the RHCE lab. I will also put updates on the blog about that.

How to Rescan SCSI Bus in Linux

I have a RHEL5 lab on my laptop, that's hosted on Vmware 7. For my RHCE prep I usually add/remove disks while the VM is up and running (hot swap). In order to make Redhat recognize the new disk you need to trigger the rescan of the SCSI bus :

echo “- - -” > /sys/class/scsi_host/hostX/scan

instead of hostX use the HBA ID. It's host0 in my case. Immediately after you can see the new disk on "fdisk -l"


NOTE : This works on 2.6 kernel only.

RHCE – Day 1

Before starting this series, I want to tell you a boring story about myself. The story begins at 2000 when I was a high school student making web design/programming to earn my pocket money:) These days I recognised a web page called Brainbench which makes online exams for certification. I passed their exam to get ceritified for HTML 4.0

From that point on, I really understood the necessity of certification because the preparation process gives you much more then the paper you earn at the end. After that, my next step was MCSE 2000. I remember that I was studying the exam on my Intel Pentium 133 running Win2k like a turtle. The preparation phase was funny but in the end as an high school student I didn’t have enough money to pay for the exam fees, so unfortunately I didn’t have a chance to be MCSE at that age :(

And then comes the collage years. This time I have a new target : Networking and Cisco Certifications. And now I have enough money coming from the scholarships ;-) After 3 years of self paced and computer based preparation and with the help of Boson Netsim and Dynamips I passed all the exams (In total 5) that are necessary for CCNA & CCNP + 1 for CCIP (QoS Exam)

After graduating from school I applied a job in a big telco vendor. They were so suprised to see a new graduate with CCNA, CCNP.  As there were a lot of paper certified people around, they want to verify this. After a very long technical interview they got convinced and hired me. 

Certification has great importance in my life. I found certification as a great tool to advance expertise about technical areas. Currently I have IWA HTML 4.0, CCNA, CCNP, CCIP, MCTS Windows Server 2008 Active Directory: Configuration, MCTS Windows Server 2008 Network Infrastructure: Configuration, MCTS Windows Server Virtualization Hyper-V and MCITP : Windows 2008 Server Admin. All of these certification tacks helped me build knowledge on varios technologies in a very proper way. But will I stop ? Of course not :) Next step is RHCE (RedHat Certified Engineer)

Why RHCE ?

- As a network and system admin the middleware I was working on is mostly UNIX based (Redhat, Solaris, Secureplatform etc..) I have enough hands on and expertise but I don’t have a real proof.
- My interview with Google reminded me the importance of Linux again.
- RHCE is lab based not one of these paper certifications.
- One of the most recognised certification by the industry.

Enough pep talk let’s begin. First the preparation materials :

1. RHEL 5 Unleashed by Tommy Fox
2. RHCE Red Hat Certified Engineer Linux Study Guide (Exam RH302), Fifth Edition byMichael Jang 
3. Slides from RH033, RH133, RH253 Classes

and the tools :

1. VmWare Workstation/Server for my laptop prep.
2. Vmware ESXi for the lab. (maybe also Hyper-V with RH Integration tools)

and of course RHEL5 iso from RHN and a new wallpaper for motivation :D

http://spinix.deviantart.com/art/LINUX-CCCP-84492543

Installation Methods

CD/DVD-ROM : Classical method for installing
Hard Disk : Requires an HD partition(xt2/3,vfat) accessible by the installer.
Network Install : NFS, FTP or HTTP based using PXE/Boot.iso
Kickstart : Unattended method of installation

NOTE : Boot.iso file can be located under RHELInstall CD1 / DVD ./images folder. 

In order to choose for an installation method use “linux askmethod” at the boot prompt

 

 

 

 

Install Phases :

- Select Language
- Select Keyboard Layout
- Installation number. (This allows us to use additional components like virtualization)
- Partition layout and RAID

IMPORTANT NOTE : If /boot or /boot/efi is a RAID. It must be RAID1.

- GRUB (Boot loader) config
- Network Config
- Packages to be installed

After Install those 2 files are created :

1. /root/install.log   --   Install Log File
2. /root/anaconda-ks.cfg   --   Sample Kickstart File based on the parameters used during the installation. I will examine this file in a future session.

Yes I know this was a less technical more personal session but next days  I will enrich the content and add more notes about my preparation track. Hope to see you in the next part of the RHCE series.