Monday, June 25, 2012

# exam rhcsa questions # rhcsa

RHCSA 6.0

Ok folks, if you're here then you have just hit jackpot because I am fresh from sitting my RHCSA exam last Friday and I passed!

Alot of blogs and sites out there provide information but its for older exams (RHCSA 5 and beyond that) so whatever I gleaned from there after going thru RHCSA classes I was told that they had made the exams easier this time around because of the high failure rate and low retake rate. I took my package that included a FREE retake (and mind you, this is really a good bargain) at about RM 4300. I had 4 days of intense classes and exam afterwards.

Unlike older exams, they don't ask you to setup an entire system from scratch but provide a VM to you on a Linux desktop. Now of course you don't get the root password of your desktop, whatever work you do its done on your VM. Your reboot, your reset, whatever changes you need to do its all done here. Don't bother with your desktop, please.

Some tips on the network configuration. Now, by default the system has NetworkManager turned on, but because you will need static IP configured it's going to clash with Network Manager so you got to turn it off and it stay that way persistently.

Hint: Commands to use

#service NetworkManager stop
#chkconfig NetworkManager off
#vi /etc/sysconfig/network-scripts/ifcfg-eth0
(input static IP config parameters here)
Once you are satisfied with changes, then give network a good old restart
#service network restart

FYI, RHEL changes their questions formatting 3-4 times a year so if you are in luck you get whatever formatting I got

These questions are going to be lightly tested or not tested at all:

Selinux booleans and contexts
FS encryption

But that doesn't mean it isn't covered, just know how it works

The following are the usual topics covered

File System Management
1. Extend existing FS
2. Resize existing FS
3. Create a new FS from scratch
4. Create swapspace 
Folks becareful with resizing FS because usually a lot of guys don't follow the syntax order and ended up corrupting their VM. This means whatever changes you had done prior to resizing was also LOST!

I'll be kind enough to put up the correct syntax to resizing a FS

Unmount your FS
#umount /test
Run fsck on the unmounted FS
#fsck -f /dev/mapper/vgtest-test
Resize the LV
#resize2fs -p /dev/mapper/vgtest-test 1024M
#lvreduce -L 1024M /dev/mapper/vgtest-test
Mount back the FS
#mount -a 
or
#mount /dev/mapper/vgtest-test /test

Hint: Group your FS questions together and do THAT first in the exam, so if you crash your VM  you don't wipe out all your other changes

Command line
1. Find command, sort command, STDIN, STDOUT, STDERR

This is basically one liner bonus questions IMHO

Cronjob
Hint: Know how to set cronjob for non root user

LDAP
This question is heavily tested in RHCSA and you really have to read the questions carefully
1. Setup autofs
2. LDAP autofs with LDAP authentication

Basically, they're going to ask you to setup autoFS with LDAP authentication to allow a user from the instructor's share drive to be able to access to your VM and cd into his home directory with certain permissions. LDAP configuration information is given, you just have to utilize your auto.master and auto.blah to make it work.

And remember, to RELOAD autofs not RESTART because on 6.0 there is a bug that hangs the system if you run service autofs restart

#service autofs reload
or
#service autofs stop
#service autofs start

Hint: Commands to use

#showmount -e instructor.example.com
#getent passwd ldapuserXX
#vi /etc/auto.master
#vi /etc/auto.blah
#system-config-authentication

Yum
1.configure yum repo
2. software update/install with yum

Ok this is really important because if you got this wrong then for the rest of the exam you won't be able to update or install any additional RPMs that you will need to complete some of your questions

#vi /etc/yum.repos.d
#vi blah.repo

FTP & Webserver
1. FTP with anonymous user with RW permissions
Hint: vsftpd
2. Configure a web server

Hint : httpd and wget

Firewall tips

This is not RHSCA 5, if you disable firewall you only lose 5 marks or so, NO! I was told that you lose more than that if you disable your firewall so if I were you I would leave the firewall turned on as it is and only allow communications with the ports that I need. I was lazy so I just enabled all the ports I saw in scroll down list LOL so all my services were working

 User & Group Management
1. SUID, GUID, sticky bit
2. ACLs

Hints: No hints, this is like bonus question

And finally, reboot reboot and reboot to make sure your changes are persistent
I finished my paper and I had 20 mins to spare!

I was browsing thru the names for the exam and came across a familiar name of someone from my old company and fancy that I never saw him at the exam. Most likely he missed it because he was a late riser! LOL!

Good luck to you all and I hope you fail pass

26 comments:

  1. Why would you want to disable NetworkManage? You can still edit the eth0 interface and restart network services just fine afterwards. The only thing NetworkManager provides is easier access to configure the network adapter. I'm going for my exam on Friday the 29th and will let you know how it goes. The LDAP automount seems to be confusing to me. Not sure if I need to modify the /etc/sysconfig/autofs to uncomment those lines or if I can just setup a basic auto.home and be done with it. Everything else I'm pretty strong on so should be ok for the exam. Thanks for posting this information.

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  2. You can't be running both NetworkManager which is meant for DHCP and configure static IP at the same time right?

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  3. You can use a static IP address with NetworkManger still on. I had one more question about the exam. I imagine they start you off where you have to reset the root password by logging into single user mode. Then configuring the network. All this is probably done in runlevel 3 with no gui correct? From then on, do they give you access to create a repository to install additional tools? Just trying to figure out if I have to do everything in runlevel 3 or if I will have access to some of the gui tools.

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  4. The vm itself is in gui, fear not ask the prerequisite info is given to you...you must have completed your exam today, how did it go?

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  5. Exam went well. I was the first one finished. I had a similar line of questions that you had. Having the gui almost made it too easy. I do not have my results back yet. They say 3 business days is what they told the class. I didn't have to revisit any of the topics and and double and triple checked everything. Did multiple reboots etc... I feel like I should have a perfect score, so I will keep you posted when my results come in.

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  6. Thanks for sharing and Conraz for clearing out.

    Wondering is there any virtual machine install?

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  7. @tcb good luck, I got my results on the night of the exam..they're kind of cheap tho, all I got was PDF. could have been sweeter PRINTED!

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  8. Got my results back on Saturday afternoon. Scored a perfect 300 on the exam. I felt that I scored perfect before I even left the test facility, but one never knows how they score things, so I was curious to see what the results would be. In some respects the exam was easier then what I thought it would be, but in other respects you do have to know the material very well because the time limit of 2.5 hours is a tight window to perform all of the objectives they have you do. I feel the exam is a good fair test of knowledge and skills and that anyone that passes the exam should be a pretty decent linux admin. Good luck to anyone else taking the exam going forward. There is no way to really cheat this exam. You either know the material or you don't.

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  9. Pls ur EmailId

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  10. You can email me at:

    tcb121@yahoo.com

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  11. Hello Brocade, congratulations for your RHCSA.

    I will present the exam soon. I'm confused about automounter question. Is it enough with:

    1. Uncomment those five options in auto.master

    2. Create a auto.home and configure with:

    * server:/dir/&

    And reload autofs?

    Thank you for your help.

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  12. uncomment five options in auto.master? better get back to the books!

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  13. RHCSA..I've exam on wednesday, is it mandatory to enable or disabled firewall? what if i flush iptable and restart networkmanager service? i'm i doing wrong here?

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  14. keep firewall on,enable port connections for services you will use. eg vsftpd, ftp, apache, http, www...

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    Replies
    1. Dear Brocade Blue
      do you know if the RHCSA exams is the same in all the world? I'm from South America and in my exam I asked for that question (disable firewall) and the examinator told me that it won't have problem, so I disabled firewall.
      This is valid for EX200 exam. Red Hat 6.0
      regards

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    2. Hi mate, they have the same questions everywhere. If u didn't lose marks and passed then well I guess they have changed their formatting/rules again. I took mine in 2012

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  15. Hi guys,
    I have become an RHCSA less than 13 days ago. Let me give you some tips.

    Before you can saw the exam questions you have to change the password of the root, in order to do that you have to restart the VM in quiet 1.
    Next you can change the network configuration as the exam describe.

    Another point is about the Firewall. In the exam is valid to do that:
    - service iptables stop
    - iptables -F
    - service iptables save
    - service iptables start.

    And as Brocade Blue said: Is important that you do: chkconfig Network Manager off in order avoid any conflict during your exam.
    regards.

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    Replies
    1. LOL i had left out the root password reset intentionally. Its the first thing you have to do, in order to "unlock" the network question, which will unlock the remaining of the exam questions

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  16. Hi,
    Brocade blue,

    Don't you think the following should be otherway round. I mean lvreduce should come first?

    Resize the LV
    #resize2fs -p /dev/mapper/vgtest-test 1024M
    #lvreduce -L 1024M /dev/mapper/vgtest-test

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  17. Hi kashif, no its the other way around. Try your command s out on your test machine u will get an error n most likely to corrupt your fs.

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  18. I think you are right.
    Basically if you want to extend the file system first you need to extend lvm and then resiz2fs the fs to increase appropriately on the other hand if you want to reduce it then you need to resize2fs (reduce the file system first ) and then reduce the lvm.

    Have RHCA exam this Friday!

    Thanks

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  19. Hi,

    Thanks for your advices. I have only one doubt, when you say to configure autofs ldap, is it enough to configure auto.master pointing to an auto indirect map ? or is it needed to modify parameters like these LDAP_URI="ldap:///dc=example,dc=com" and files like this /etc/autofs_ldap_auth.conf ????

    Thanks a lot!

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  20. Hi BB,

    I passed the RHCSA about a month ago, and no surprises, LDAP and autofs came up.

    I feel I missed some easy points as I managed to get the LDAP authentication working, but didn't know where to start with autofs. The main reason for this was not having a suitable LDAP / autofs server to practice on, so I was just working from what I could remember reading from books.

    Since the exam, I've put together a kickstart file, which builds an LDAP server, with test accounts, certificates and NFS shares suitable for autofs connections. It seems to match the functionality of the LDAP server provided in the exam.

    Full details are on my web site at http://oddwires.co.uk/rhcsa/

    Hopefully it will help someone with their studies.

    Cheers

    Tony

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    Replies
    1. Hi Tony. I checked your site and commented! Thanks for visiting and spreading the word. RHCSA is no monster, plenty of practice and anyone can pass, you're proved it in less than 6 months!

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