vxvm interview questions

1. How do you replace a failed boot disk under meta in solaris? Step by step explanation?

2. How do you remove meta only for the root slice? remaining slices should run under meta?

3. what you would do if you want to replace a slice using metareplace option?

4. what is the significance of 51% state database replicas in SVM?

5. what are the common errors you find in Solaris Volume manager?

6. You have a boot disk under svm, the machine fails to boot and remains in ok prompt? what could be the possible reason?

7. metastat -p shows a metavolume needs replacement. Metavolume is a single way mirror only. Actually you find disk and metavolumes are ok and I/O is happening to the filesystems… how will you remove the metareplace message that comes out of metastat.

8. How to create a shared disk group in VxVM?

9. What is the difference between private and public regions in Veritas Volume manager?

10. what would you do if the private region of a particular disk group is full? What are the design considerations for the size of private region in Vxvm disk group?

11. How to replace a corrupt private region? in vxvm 3.5 and greater versions…

12. How would you convert a volume from gen to fsgen? why should you do that?

13. How can you unencapsulate a boot disk in VxVM?

14. How to identify multiple paths for a disk.

15. What is the difference between Vxdmp and EMC powerpath?

16. vxdisk -o alldgs list o/p shows some disk groups in braces… What does that signify?

17. what are the various layouts that are available in VxVM?

18.What is a layered volume? how to create it using vxmake?

19.How to quickly mirror a volume, if the volume is empty?

20. How to grow a volume?

21. What is the difference between failing and failed disks?

22. How to replace a failed disk in Veritas?

23. Plex is in a disabled state. How will you recover? what are the steps to follow?

24.what is the difference between detached and disassociate state of plexes?

25. Whats the boot process of VxVM?

26. Whats the difference between SVM and VxVM? What would you recommend to your clients? why?

27.What are the various clusters you have worked on?

28. Which cluster is better VCS or Sun cluster?

29. Compare and contrast VCS and Sun Cluster.

30.how will you start VCS service? What are the configuration files in VCS?

31. How would switch a service group?

32. How would you freeze a service group?

33. What is a Split brain scenario ?

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# 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.

# 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 >

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

# 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.

# 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.

# 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

# 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.

# 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.

# 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.

# 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]