Wednesday, April 15, 2009

Veritas volume manager certification questions

1. A Volume Manager disk can be divided into one or more ________.
• a. disk groups
• b. partitions
• c. slices
• d. subdisks
2. What does an active/passive array provide?
• a. load balancing using minimum I/O policy
• b. high availability in the event of a total array failure
• c. load balancing using the round robin I/O policy
• d. high availability in the event of a path failure
3. Which configuration step must be completed prior to assigning a new disk to a disk group?
• a. initialize the disk
• b. create subdisks
• c. assign disk space to volumes
• d. configure the volume disk pool
4. Which vxdisk command options display disk information and the disk group status?
• a. -o dg list
• b. -o alldgs list
• c. -o list alldgs
• d. -o list dg
5. If the datadg disk group has a disk group version of 50, what occurs when you run the vxdg upgrade datadg command with no other options?
1. a. The disk group is upgraded by one disk group version level, in this case, to version 60
2. b. You receive an error stating that the disk group version must be specified
3. c. The disk group is upgraded to the latest disk group version
4. d. The current disk group version is displayed and no further action is taken
6. Output from the vxprint command displays information stored in the _______.
• a. private region
• b. public region
• c. partition table
• d. dirty region log
7. Which command removes the datavol volume from the datadg disk group?
• a. vxassist -g datadg remove volume datavol
• b. vxremove -g datadg remove volume datavol
• c. vxassist -g datadg destroy volume datavol
• d. vxdg -g datadg destroy volume datavol
8. Which statement is true about the relationship between a Volume Manager volume and the corresponding file system?
• a. Starting the volume will start the file system
• b. The file system must be mounted to stop the volume
• c. The file system must be unmounted to stop the volume
• d. Starting the file system will start the volume
9. Which command forces the daemon to reread all the drives in the system?
• a. kill ?HUP vxiod
• b. vxdisk rescan
• c. vxdctl enable
• d. vxprint -voldstart
10. Which command can be used to remove a disk interactively?
• a. vxdiskadm option “remove a disk”
• b. vxdisk remove -f -i
• c. vxdisk relocate -f -i
• d. vxdiskadm option “relocate subdisks”
11. The datadg disk group contains four disks. A 100 MB volume named datavol is concatenated using two disks. There are no other volumes in the disk group. There are three processes performing random reads that are 512K in size on the volume. Output from a vxstat command indicates that all I/O activity occurred mostly on one of the two disks.

Which action will most evenly distribute the I/O across all disks in the disk group?
• a. Mirror the volume using the two unused disks
• b. Remove the two unused disks from the disk group
• c. Resize the volume to use all of the disks
• d. Stripe the volume across all four disks
12. Which layout options are available when using the vxassist command to create a layered volume? (Choose two)
• a. concat-mirror
• b. mirror-concatenate
• c. stripe-mirror
• d. mirror-stripe
• e. concatenate-stripe
• f. stripe-concatenate
13. Which menu option within the vxdiskadm utility can be used to create a new disk group?
• a. Add or initialize one or more disks
• b. Add or initialize one or more disk groups
• c. Make a disk available for hot-relocation use
• d. Enable access to (import) a disk group
14. What are the benefits of enclosure-based naming? (Choose three)
• a. easier fault isolation
• b. improved array availability
• c. device-name independence
• d. improved SAN management
• e. improved disk performance
15. Which command creates a 10 GB volume named datavol in the datadg disk group, assuming that the /etc/default/vxassist file does NOT exist on the system?
• a. vxvmvol -g datadg new 10g datavol
• b. vxvol -g datadg create 10g datavol
• c. vxassist -g datadg make datavol 10g
• d. vxdisk -g datadg 10g newvol datavol
16. Online resizing of a Volume Manager volume and file system requires that the file system is _____.
• a. in the bootdg disk group
• b. checked before the process
• c. shared across disk groups
• d. mounted during the process
17.Which command displays the contents of the volboot file?
• a. vxvolboot list
• b. vxcat volboot
• c. vxdctl list
• d. vxconfig volboot
18. What are the characteristics of a space-optimized snapshot? (Choose two)
• a. contains compressed primary data
• b. references the primary data
• c. requires less space than a full-sized point-in-time copy
• d. initially contains a complete copy of primary data
• e. performs an automatic atomic-copy resynchronization
19. Which Veritas Volume Manager command displays average volume read and write times?
• a. vxprint
• b. vxstat
• c. vxtrace
• d. vxinfo
20. What is the recommended next step to be performed after a failed disk has been physically replaced?
• a. Logically replace the disk in volume Manager
• b. Unrelocate any relocated Volume Manager subdisks to the new disk
• c. Synchronize any STALE plexes
• d. Ensure that the operating system can access the disk
21. Which commands can be used to manage dynamic multipathing? (Choose two)
• a. vxddladm
• b. vxdiskadm
• c. vxdmpadm
• d. vxpathadm
• e. vxassist
22. Which task related to protecting the Volume Manager configuration has the steps “precommit” and “commit” associated with it?
• a. restore
• b. backup
• c. replace
• d. remove
Answers: 1-d, 2-d,3-a, 4-b, 5-c, 6-a, 7-a, 8-c, 9-c,10-a,11-d, 12-a&c, 13-a, 14-a&c&d, 15-c, 16-d, 17-c, 18-b&c, 19-b, 20-d, 21-b&c, 22-a


Disk Group Version New Features Supported Previous Version Features Supported
90 • Cluster Support for Oracle Resilvering
• Disk Group Move, Split and Join
• Device Discovery Layer (DDL)
• Layered Volume Support in Clusters
• Ordered Allocation
• OS Independent Naming Support
• Persistent FastResync 20, 30, 40, 50, 60, 70, 80
80 • VERITAS Volume Replicator (VVR) Enhancements 20, 30, 40, 50, 60, 70
70 • Non-Persistent FastResync
• VERITAS Volume Replicator (VVR) Enhancements
• Unrelocate 20, 30, 40, 50, 60
60 • Online Relayout
• Safe RAID-5 Subdisk Moves 20, 30, 40
50 • SRVM (now known as VERITAS Volume Replicator or VVR) 20, 30, 40
40 • Hot-Relocation 20, 30
30 • VxSmartSync Recovery Accelerator 20
20 • Dirty Region Logging
• Disk Group Configuration Copy Limiting,
• Mirrored Volumes Logging
• New-Style Stripes
• RAID-5 Volumes
• Recovery Checkpointing

To list the version of a disk group, use this command:


Veritas Volume Manager Command Line Examples

Tags:
• Veritas VM


Volume Manager CLI examples:
---------------------------


display disk listings:

# vxdisk list



display volume manager object listings

# vxprint -ht



display free space in a disk group

# vxdg -g free



list all volume manager tasks currently running on the system

# vxtask list



add a disk to Volume Manager (devicename = cXtXdX) (prompt driven)

# vxdiskadd



designate/remove a disk as a hot-relocation spare

# vxedit set spare=on

# vxedit set spare=off



rename a disk

# vxedit rename



reserve/unreserve a disk (space won't be allocated unless specifically mentioned in vxassist)

# vxedit set reserve=on

# vxedit set reserve=off



take a disk offline (first remove the disk from its disk group) (devicename=cXtXdXs2)

#vxdisk offline



remove a disk

(first, stop any applications associated with the volume,
unmount the volume, stop the volume,
if you need the data on the disk, move the volumes to another disk or back up volume)


--removing the disk from its disk group:

# vxdg -g rmdisk


--remove the disk from volume manager control (devicename=cXtXdXs2)

# vxdisk rm



display multipath information

# vxdisk list



create a disk group

(see 'add a disk to volume manager - if the group does not exist, you will be prompted)



upgrade a disk group

--list disk group version

# vxdg list


--upgrade disk group to highest version currently running

# vxdg upgrade



destroy a disk group

# vxdg destroy



display disk group information

# vxdg list

# vxdg list



move a disk group

(stop any applications associated with all volumes in the disk group,
unmount and stop all volumes in the disk group:

--deport (disable local access) the disk group to be moved on first system

# vxdg deport


--import (enable local access) the disk group and its disks from the second system

# vxdg import


--start all volumes in the disk group on the second system

# vxrecover -g -sb

or # vxvol -g startall



estimating maximum volume size (any_valid_type = raid5, stripe, mirror)

# vxassist -g maxsize layout=



create a concatenated volume (length examples = 15g, 15m)

# vxassist -g make



create a striped volume (length examples = 15g, 15m)

# vxassist -g make layout=stripe \




create a raid5 volume (without logging) (length examples = 15g, 15m)

# vxassist -g make layout=raid5,nolog \




create a raid5 volume (with logging) (length examples = 15g, 15m)

# vxassist -g make layout=raid5,log \




create a mirrored volume (without DRL) (length examples = 15g, 15m)

# vxassist -g make layout=mirror,nolog \




create a mirrored volume (with DRL) (length examples = 15g, 15m)

# vxassist -g make layout=mirror,log \




mirror an existing volume

# vxassist mirror



mirror all volumes within a disk group

# vxmirror -g -a



mirror the root (boot) disk

EEPROM variable "use-nvramrc?" must be set to true

# vxrootmir -v



remove a mirror (use 'vxprint -g -ht' to get plexname)


# vxplex -o rm dis



add a log to an existing volume

# vxassist addlog



remove a log from an existing volume

# vxassist remove log



create a raid 0+1 volume (without DRL)

# vxassist -g make layout=mirror-stripe,nolog \
nmirror=# nstripe=#



create a raid 1+0 volume (without DRL)

# vxassist -g make layout=stripe-mirror,nolog \
nmirror=# nstripe=#



resize a volume

# vxassist -g growto

# vxassist -g growby

# vxassist -g shrinkto

# vxassist -g shrinkby



estimate how much a volume can grow

# vxassist -g maxgrow



remove a volume

(stop all applications associated with the volume,
unmount volume (remove /etc/vfstab entry))

--stop volume

# vxvol stop

-- remove volume (for raid 1+0, use 'rf-rm')

# vxedit -r rm

or # vxassist remove volume



change the volume read policy

# vxvol rdpol

# vxvol rdpol prefer



change volume attributes

# vxedit set =



resize a filesystem (ufs cannot be shrunk, only grown)

# vxresize -g +
# vxresize -g -



join subdisks (must be in the order of offset on disks)

# vxsd join


»
create a striped volume (length examples = 15g, 15m)
Submitted by Anonymous (not verified) on Wed, 07/16/2008 - 04:41.
The syntax is incorrect for:
create a striped volume (length examples = 15g, 15m)
# vxassist -g make layout=stripe \

It should be something like this:
# vxassist -g testdg make testdgvol1 285503488 layout=stripe alloc=disk1,disk2,disk3,disk4
This brings the credibility of the rest of this document into question; You have not specified which version of Veritas this applied to ;P
# vxdg list dgname
To upgrade a disk group to the highest version supported by the release of VxVM that is currently running, use this command:


# vxdg upgrade dgname
By default, VxVM creates a disk group of the highest version supported by the release. For example, VERITAS Volume Manager 3.2 creates disk groups with version 90.
It may sometimes be necessary to create a disk group for an older version. The default disk group version for a disk group created on a system running VERITAS Volume Manager 3.2 would be 90. Such a disk group would not be importable on a system running VERITAS Volume Manager 2.3, which only supports up to version 40. Therefore, to create a disk group on a system running VERITAS Volume Manager 3.0 that can be imported by a system running VERITAS Volume Manager 2.3, the disk group must be created with a version of 40 or less.
To create a disk group with a previous version, specify the -T version option to the vxdg init command. For example, to create a disk group with version 40 that can be imported by a system running VxVM 2.3, use the following command:


# vxdg -T 40 init newdg newdg01=c0t3d0


This creates a disk group, newdg, which can be imported by VERITAS Volume Manager 2.3. Note that while this disk group can be imported on the VxVM 2.3 system, attempts to use features from VERITAS Volume Manager 3.0 and later releases will fail.

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