NS0-155 Netapp Data ONTAP 7-Mode Administrator Free Practice Exam Questions (2025 Updated)

When you rejoin split aggregates, Data ONTAP mirrors the data from one aggregate to the other and destroys data that existed on that aggregate before the rejoin.

https://library.netapp.com/ecmdocs/ECMP1196991/html/GUID-B9CB3DA8-E1AF-4BAC-A85B-64C009010F4A.html

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/GUID-ED9C09EF-3F61-41FE-B8F1-36356C5FEC5F.html

The rules for the selection of disks or array LUNs, for using as mirrored aggregates, are as follows:

Disks or array LUNs selected for each plex must be in different pools.

The same number of disks or array LUNs must be in both the plexes.

Disks are selected first on the basis of equivalent bytes per sector (bps) size, then on the basis of the size of the disk.

If there is no equivalent-sized disk, Data ONTAP uses a larger-capacity disk, and limits the size to make it identically sized.

Data ONTAP names the plexes of the mirrored aggregate.

https://library.netapp.com/ecmdocs/ECMP1196991/html/GUID-F5F241AF-50C0-4FF3-8C01-96958581C4D9.html

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.

https://library.netapp.com/ecmdocs/ECMP1196890/html/man1/na_aggr.1.html

The following commands are available in the aggr suite:

If you use the -d disk1 [ disk2 ... ] argument, the node creates the aggregate with the specified spare disks disk1, disk2, and so on. You can specify a space-separated list of disk names. Two separate lists must be specified if the new aggregate is mirrored. In the case that the new aggregate is mirrored, the indicated disks must result in an equal number of disks on each new plex.

The disks in a plex are not permitted to span spare pools. This behavior can be overridden with the -f option.

The same option can also be used to force using disks that do not have matching rotational speed. The –f option has effect only when used with the -d option specifying disks to use.

The -m option can be used to specify that the new aggregate be mirrored (have two plexes) upon creation. If this option is given, then the indicated disks will be split across the two plexes. By default, the new aggregate will not be mirrored.

aggr mirror aggrname

The -n option can be used to display the command that the system will execute without actually making any changes. This is useful for displaying the automatically selected disks, for example.

https://library.netapp.com/ecmdocs/ECMP1196979/html/man1/na_fcp.1.html

fcp show adapter [ -v ] [ adapter ]

If no adapter name is given, information about all adapters are shown.

This command displays information such as nodename/portname and link state about the adapter.

If the -v flag is given, this command displays additional information about the adapters.

IPSec is an encryption transport that can be used to secure any IP traffic including iSCSI.

The reference for this questionis an old version of a TR. It is likely that this question will be removed from the NSO-155 exam.

The svconfigpackager is a binary in the OSSV client which can be used to create an unattended installation package using an answer file.

http://backdrift.org/man/netapp/man1/na_quota.1.html

quota resize volume

Adjusts currently active quotas in the specified volume to reflect changes in the /etc/quotas file. For instance, if you edit an entry in /etc/quotas to increase a user's quota, quota resize will cause the change to take effect. The volume name may be omitted if the system has only one volume. quota resize can be used only when quotas are already on. Because it does not rescan the file system to compute usage, quota resize is faster than turning quotas off and then on again. quota resize will apply all updated entries in /etc/quotas; however, it will generally ignore newly added entries. A newly added entry will only take effect if the corresponding user or group has an active quota as a result of updating a file subject to default quotas.

https://communities.netapp.com/servlet/JiveServlet/previewBody/4803-102-1-6405/tr-3548.pdf

It is important to remember that this is the case only when a complete site is lost. In the case of a failed controller at one of the sites, a normal cluster failover occurs. Due to the operation of SyncMirror, there is also added protection from multidrive or complete shelf failures. When a storage controller fails in an active-active configuration, the partner detects the failure and automatically (if enabled) performs a takeover of the dataserving responsibilities from the failed controller. Part of this process relies on the surviving controller being able to read information from the disks on the failed controller. If this quorum of disks is not available, then automatic takeover won’t be performed. In a MetroCluster configuration, manually executing a single command will allow a takeover to occur in spite of the lack of a quorum of disks. This "forced takeover" process breaks the mirrored relationships in order to bring the failed controller’s volumes on line.

forcetakeover -d is very dangerous. Not only can it cause data corruption, if not used carefully, it can also lead to a situation where both the node and its partner are operational (split brain). As such, it should only be used as a means of last resort when the takeover and forcetakeover commands are unsuccessful in achieving a takeover. The operator must ensure that the partner node does not become operational at any time while a node is in a takeover mode initiated by the use of this command. In conjunction with RAID mirroring, it can allow recovery from a disaster when the two nodes in the HA pair are located at two distant sites.

https://communities.netapp.com/servlet/JiveServlet/previewBody/4791-102-2-13466/tr-3466.pdf

Pg 17

OSSV hosts listen for communications from NDMP manager applications on port 10000 by default.

https://library.netapp.com/ecmdocs/ECMP1196995/html/GUID-577EDC41-FEA0-4987-8F04-55E736962FD1.html

Always unmount the LUN before you run the snap restore command on a volume containing the LUN or before you run a single file SnapRestore of the LUN. For a single file SnapRestore, you must also take the LUN offline.

The fstab file reflects the defined filesystem mount paths (including NFS mounts).

Always check network connectivity when a problem arises with a network service.

The exportfs command will display the active exports on the storage system.

http://wafl.co.uk/ndmpcopy/

Think of ndmpcopy as a sort of ftp for SAN. You can use it to copy files from one volume to another. Because the file is read from one volume and written to another, the constraints of volume types are not an issue.

http://www.ntapgeek.com/2011/12/how-in-place-expansion-works.html

To upgrade an aggregate in-place, the only available method is to add disks to expand the aggregate to >16TB.

There is an obscure method using diag mode but that is not supported or mentioned in the exam content. The answer is always add disks to grow past 16TB, or migrate.

iscsi status - displays current status of the iSCSI service.

http://wafl.co.uk/iscsi/#sthash.GzOHA2Tj.dpuf

The 'lun' in the path is irrelevant. The 0 at the end of each statement denotes the LUN ID.

LUN IDs must be unique per igroup.