NetApp NetApp Certifications NS0-155 Questions & Answers

• Question 81:

  Which keyword alone can be used to convert an asynchronous SnapMirror relationship to a synchronous SnapMirror relationship?

  A. sync

  B. cksum

  C. src_con

  D. outstanding

  Correct Answer: A

  To convert an asynchronous SnapMirror relationship to a synchronous SnapMirror relationship, on the administration host, edit the snapmirror.conf file on the destination system to change the schedule to sync. https://library.netapp.com/ecmdocs/ECMP1196991/html/GUID-A78BDBC9-610B-4555-A2DE- CE6861D92614.html

• Question 82:

  SnapMirror will automatically try to restart a transfer after ___________.

  A. an initial transfer is interrupted

  B. a manual update is interrupted

  C. a transfer interrupted by reboot

  D. a scheduled incremental update is interrupted

  Correct Answer: D

  If a scheduled transfer fails (for example, due to network failure), SnapMirror automatically retries the transfer the next minute. http://hd.kvsconsulting.us/netappdoc/733docs/html/ontap/onlinebk/GUID-511EAA86-069A-42E8- B62E- 3168C7F0A83D.html

• Question 83:

  Which three statements apply to the SnapMirror visibility_interval argument? (Choose three.)

  A. The default interval value is five minutes.

  B. The smallest interval value supported is 30 seconds.

  C. This variable controls the view of the data on the destination system.

  D. By setting a value, you specify the amount of time before an automatic snapshot is created on the source volume that is synchronously mirrored.

  Correct Answer: BCD

  http://www.netapp.com/us/media/tr-3326.pdf http://backdrift.org/man/netapp/man5/na_snapmirror.conf.5.html http://hd.kvsconsulting.us/ netappdoc/733docs/html/ontap/onlinebk/GUID-47724B21-7C7E-4AC9- A497-9505B42C27AF.html

  With SnapMirror Sync and SnapMirror Semi-Sync, changes to the source volume do not show up immediately on the destination volume, even though the changes have been replicated. The changes are first shown after the source system creates an automatic Snapshot copy of the source volume. Snapshot copies created on the source volume are immediately propagated to the destination volume. The automatic Snapshot copies are created every three minutes by default.

  To change the interval for automatic Snapshot copies, change the visibility_interval in the snapmirror.conf file; however, performance can degrade if set to a smaller interval because frequent Snapshot copies cause additional processing such as cache consistency checking on the destination system.

  There is also a disadvantage in setting this to a large value. When the connection between the systems has an outage and SnapMirror goes into asynchronous mode, SnapMirror uses the last common Snapshot copy to transition into synchronous mode. This means that all data from the last valid common Snapshot copy will need to be replicated from the source to the destination storage system. If the visibility_interval is set to a large value, a large amount of data might have to be transferred and it might take longer time for SnapMirror to transition into synchronous mode. For these reasons, keep the default value of three minutes.

  visibility_interval

  The value for this argument is a number optionally followed by the suffixes: s (seconds), m (minutes) or h (hours). If a suffix is not specified, value is interpreted as seconds. This argument controls the amount of time before an automatic

  snapshot is created on the source volume that is synchronously mirrored. The value is the number of seconds between automatically created snapshots. The default value is 3 minutes. A small number here can negatively affect the

  performance of the mirror. This argument is ignored for asynchronous mirrors.

  visibility_interval={xs | xm | xh}

  Determines the amount of time before an automatic Snapshot copy is created on the source volume that is being replicated using synchronous or semi-synchronous SnapMirror. When replicating synchronously or semisynchronously, using

  SnapMirror, changes to the source volume do not show immediately on the destination volume, even though the changes have been replicated. The changes are shown only after the source system takes an automatic Snapshot copy of the

  source volume. This event occurs every three minutes by default.

  You can change the interval for automatic Snapshot copies, but performance can degrade if you set smaller intervals because Snapshot copies are taken more often. The smallest interval you can set is 30 seconds.

  Note: The s, m, and h suffixes specify seconds, minutes, and hours, respectively.

• Question 84:

  Which two statements apply to the fs_size_fixed volume option? (Choose two.)

  A. The default setting is on.

  B. This option is automatically set to be on when a volume becomes a SnapMirrored volume.

  C. This option turns to off after the snapmirror break command is issued for the relationship.

  D. This option causes the SnapMirror destination volume to remain the same size and not grow or shrink when a SnapMirrored volume relationship is broken.

  Correct Answer: BD

  This option causes the file system to remain the same size and not grow or shrink when a SnapMirrored volume relationship is broken, or when a vol add is performed on it. This option is automatically set to be on when a volume becomes a SnapMirrored volume. It will remain on after the snapmirror break command is issued for the volume. This allows a volume to be SnapMirrored back to the source without needing to add disks to the source volume. If the volume size is larger than the file system size, turning off this option will force the file system to grow to the size of the volume. The default setting is off. http://wafl.co.uk/vol-2/#sthash.DbEHR4YS.dpuf

• Question 85:

  In a volume SnapMirror relationship, the source and destination volumes must be the same size.

  A. True

  B. False

  Correct Answer: B

  In an active volume SnapMirror relationship, the size of the source and destination file systems is identical.

  However, the size of the destination volume can be larger than or equal to the size of the source volume. The size of the file systems must be identical to allow the source to be restored from the destination.

  https://library.netapp.com/ecmdocs/ECMP1196991/html/GUID-DE5EE692-81CF-4569-A703- 00B4E283CE99.html

• Question 86:

  Identify the two commands that could be entered on the SnapMirror destination storage system. (Choose two.)

  A. snapmirror resync

  B. snapmirror release

  C. snapmirror initialize

  D. options snapmirror.access on

  Correct Answer: AC

• Question 87:

  You have quiesced a SnapMirror relationship. Which command would re-establish the scheduled updates?

  A. snapmirror restart

  B. snapmirror resume

  C. snapmirror resync

  D. snapmirror update

  Correct Answer: B

  snapmirror resume destination Resumes transfers to destination. The snapmirror resume command can be used either to abort a snapmirror quiesce in progress or undo a previously completed snapmirror quiesce. The command restores the state of the destination from quiescing or quiesced to whatever it was prior to the quiesce operation. http://wafl.co.uk/snapmirror/#sthash.5u3eilbK.dpuf

• Question 88:

  Which command would you use to verify that the iSCSI service is running?

  A. iscsi protocol

  B. iscsi service

  C. iscsi show

  D. iscsi status

  Correct Answer: D

  iscsi status - displays current status of the iSCSI service. http://wafl.co.uk/iscsi/#sthash.GzOHA2Tj.dpuf

• Question 89:

  When you are setting up SnapMirror, which three are replication pre-requisites? (Choose three.)

  A. The source volume must be offline.

  B. SnapMirror must be licensed for each storage system.

  C. If you are replicating a volume, you must create a restricted volume to be used as the SnapMirror.

  D. The capacity of the SnapMirror destination must be greater than or equal to the capacity of the source destination volume.

  Correct Answer: BCD

  You need to fulfill a set of prerequisites before you can use SnapMirror:

  - You must purchase and enable the SnapMirror license. If the SnapMirror source and destination are on different systems, you must enable the SnapMirror license on each system.

  -For SnapMirror volume replication, you must create a restricted volume to be used as the destination volume.

  SnapMirror does not automatically create a volume. For information about how to create volumes, see the section on organizing data using volumes and qtrees in the Data ONTAP Storage Management Guide for 7-Mode.

  - For SnapMirror volume replication, the destination system must use a version of Data ONTAP that is the same as or later than that of the SnapMirror source system. https://library.netapp.com/ecmdocs/ ECMP1196991/html/GUIDED9C09EF-3F61-41FE-B8F1- 36356C5FEC5F.html

• Question 90:

  A volume is SnapMirrored hourly. You revert the volume using a snapshot that was created two days ago. Which command continues the relationship?

  A. SnapMirror initialize

  B. SnapMirror quiesce

  C. SnapMirror resume

  D. SnapMirror resync

  E. SnapMirror update

  Correct Answer: D

  You can use the snapmirror resync command to reestablish the connection between the source and the destination. This command is applied after the SnapMirror relationship between the source and destination is broken. https://library.netapp.com/ecmdocs/ECMP1196991/html/GUID-5D846D24-0903-4982-A429- 71AE5C0F9033.html