Sunday, February 24, 2008

VXVM interview questions

One more on VXVM

1. Name the mandatory disk group in VxVM 3.5 ? How will you configure VxVM in 3.5 ?
ANS: rootdg is the mandatory disk group in VxVM 3.5, vxinstall is the command to configure VxVM, It will create the disk groups, initializes the disks and adds them to the group.

2. How will you create private and shared disk group using VxVM ?
ANS: For Private DG:
Command: vxdg init

For Shared DG:
Command: vxdg -s init < disk1 disk2 disk3 >

3. Which are the different layouts for volumes in VxVM ?
ANS: mirror, stripe, concat (default one), raid5, stripe-mirror, mirror-stripe.

4. What is the basic difference between private disk group and shared disk group ?
ANS: Private DG: The DG which is only visible for the host on which you have created it, if the host is a part of cluster, the private DG will not be visible to the other cluster nodes.
Shared DG: The DG which is sharable and visible to the other cluster nodes.

5. How will you add new disk to the existing disk group ?
ANS: Run vxdiskadm command, which will open menu driven program to do various disk operations, select add disks option or you can use another command vxdiskadd.

6. How will you grow/shrink the volume/file system ? What is the meaning of growby and growto options ? What is the meaning on shrinkto and shrinkby options ?
ANS: vxassist command is used to do all volume administration, following is the description and syntax.

Growby option: This is will grow your file system by adding new size to the existing file system.

Growto option: This will grow your file system as per the new size. This WILL NOT ADD new size to the existing one.

Shrinkby option: This will shrink your file system by reducing new size from existing file system.

Shrinkto option: This will shrink your file system as per the new size. This WILL NOT REDUCE the file system by reducing new size.

Command:
vxassist -g [growto, growby, shrinkto, shrinkby] length

7. How will you setup and unsetup disks explicitly using VxVM ?
ANS: You can use /etc/vx/bin/vxdiskunsetup to unsetup the disk, and /etc/vx/vxdisksetup to setup the disk.

8. How will you list the disks, which are in different disk groups ?
ANS: vxdisk list is the command will list the disks from the DG which is currently imported, you can check the same using vxprint command too. vxdisk -o alldgs list command list all the disks which are in different dg's.

9. What is the private region in VxVM ?
ANS: Private region stores the structured VxVM information, it also stores the disk ID and disk geometry. In short words it has metadata of the disk.

10. If, vxdisk list command gives you disks status as "error", what steps you will follow to make the respective disks online ?
ANS: If you faced this issue because of fabric disconnection then simply do vxdisk scandisks, otherwise unsetup the disk using using /etc/vx/bin/vxdiskunsetup and setup the disks again using /etc/vx/bin/vxdisksetup, this will definitely help! [ /etc/vx/bin/vxdiskunsetup will remove the private region from the disk and destroys data, backup the data before using this option]

9 comments:

Anonymous said...

Technical Interview Questions and Answers

Thanks again
Ankur

SIMHA said...

how do replace the failed disk in veritas volume manager by using mirror and raid5 concepts?
_simha

SIMHA said...

procedure to configure NFS and NIS concepts on solaris volume manager?
-simha

SIMHA said...

how to root mirroring in SVM and VxVM?

Unknown said...

Hi Simha,

No way I am SVM or VxVM expert however here are the answers to your question which I found with google.

how to root mirroring in SVM and VxVM?
-->http://linuxshellaccount.blogspot.com/2007/11/basic-root-disk-mirroring-with-solaris.html

procedure to configure NFS and NIS concepts on solaris volume manager?
-->Can you elaborate your question?

how do replace the failed disk in veritas volume manager by using mirror and raid5 concepts?
-->http://unixway.com/vm/veritasvm/failedbootdisk.html#insertreplacement

Unknown said...

Here's a good cheat sheet on VxVM,
http://www.darklab.net/resources/veritas/veritas_lvm_cs.htm

Madhusudhana Reddy said...

Thank u very much mohit for vxvm docs

kumar said...

hi mohit .

i have one doubt ..actually i did solaris admin course and veritas volume manger..after words i did a job .not a subject related .now iam doing linux admin..and shell scrippting . i want to put resume on 3 years may iknow how the oppurtinuties on linux. i want to put 2 years solaris .one year linux ..can u give your suggestion.

Unknown said...

Hi Kumar,

Thanks for stopping by on my blog and regarding your question on opportunities in Linux, yes you have good market for it however at the moment I feel market is down so you may face some challenges in securing a job.

Best of luck
-Mohit