NS0-155 Data ONTAP 7-Mode Administrator Questions and Answers

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.

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

iscsi security show

Display the default authentication and all the initiator specific authentication information.

Hint: Remember that the iscsi command is mostly structured "iscsi noun verb", unlike the fcp command which is structure "fcp verb noun". Example: iscsi initiator show, fcp show initiator.

All the network ports should be assigned correct port roles, and all the network ports should be in the same subnet.

https://library.netapp.com/ecm/ecm_download_file/ECMP1196907

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

The maximum cable length supported for 2Gbps is 500m, the same as the max cable length between a NetApp storage system and a FC switch.

Stretch MetroCluster (sometimes referred to as nonswitched) is simply an active-active configuration that can extend up to 500m depending on speed and cable type. It also includes synchronous mirroring (SyncMirror®) and the ability to do a site failover with a single command. See Figure 2. Additional resiliency can be provided through the use of multipathing.

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

The operator must ensure that the partner filer does not become operational at any time while a filer is in a takeover mode initiated by the use of this command

https://backdrift.org/man/netapp/man1/na_cf.1.html

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

iscsi status - displays current status of the iSCSI service.

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

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

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

aggr destroy { aggrname | plexname } [ -f ]

Destroys the aggregate named aggrname, or the plex named plexname. Note that if the specified aggregate is tied to a traditional volume, then the traditional volume itself is destroyed as well.

If an aggregate is specified, all plexes in the aggregate are destroyed. The named aggregate must also not contain any flexible volumes, regardless of their mount state (online, restricted, or offline). If a plex is specified, the plex is destroyed, leaving an unmirrored aggregate or traditional volume containing the remaining plex.

Before destroying the aggregate, traditional volume or plex, the user is prompted to confirm the operation. The -f flag can be used to destroy an aggregate, traditional volume or plex without prompting the user.

The disks originally in the destroyed object become spare disks. Only offline aggregates, traditional volumes and plexes can be destroyed.

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

sysstat reports aggregated filer performance statistics such as the current CPU utilization, the amount of network I/O, the amount of disk I/O, and the amount of tape I/O.

Volume SnapMirror Interoperability Matrix.

A baseline (aka "full") backup is always required before valid incremental backups can be made.

https://en.wikipedia.org/wiki/Multipath_I/O

Fiber Channel (FC), FCoE and iSCSI encapsulate SCSI-3. FCoE and iSCSI further encapsulate the transport within IP; hence the term IP SAN.

In computer storage, multipath I/O is a fault-tolerance and performance enhancement technique whereby there is more than one physical path between the CPU in a computer system and its mass storage devices through the buses, controllers, switches, and bridge devices connecting them.

A simple example would be a SCSI disk connected to two SCSI controllers on the same computer or a disk connected to two Fibre Channel ports. Should one controller, port or switch fail, the operating system can route I/O through the remaining controller transparently to the application, with no changes visible to the applications, other than perhaps incremental latency.

https://www.ntapgeek.com/2011/03/netapp-storage-encryption-available.html

March, 2011: "With the recent release of Data ONTAP 8.0.1, NetApp now offers full disk encryption to prevent unauthorized access to data at rest."

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

In order to restrict the NetApp secondary systems that are allowed to initiate backups from an OSSV host, the QSM Access List field can be populated with the hostname of the secondary using the OSSV Configurator utility. When using this option, make sure the “Check QSM Access List” box is enabled.

The snapvault.access option on the NetApp secondary can be used to restrict the OSSV hosts that are allowed to initiate restores from that secondary system. This option can be populated with a list of hostnames for each OSSV host. For example:

options snapvault.access host=ossv1,ossv2,ossv3

Screenshot of the svconfigurator GUI; note the QSM access list checkbox and field.

ifstat -a provides detailed statistics (multiple pages) about all network interfaces.

netstat -i provides a list of connections and open network sockets (listeners).

netdiag -n will perform a diagnostic but does not provide detailed statistics about networking.

sysstat 1 will provide performance statistics but not detailed statistics about networking.

https://library.netapp.com/ecmdocs/ECMP1196991/html/GUID-EEBC8B52-BEA9-4B49-874F-7EC78D3F602E.html

Each open systems platform, when prompted by the secondary system, transfers initial base images of specified directories to qtree locations on the secondary system.

Note: There are no primary-side Snapshot copies in Open Systems SnapVault.

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

The following commands are available in the lun suite:

Easy to use interactive mechanism for setting up initiator groups, LUNs, and mapping configuration.

lun map [ -f ] lun_path initiator_group [ lun_id ]

Maps a LUN to all the initiators in the supplied group

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

https://backdrift.org/man/netapp/man1/na_netdiag.1.html

ifstat - display device-level statistics for network interfaces

netdiag - perform network diagnostics

https://hd.kvsconsulting.us/netappdoc/801docs/html/ontap/smg/GUID-866DD79D-D2A6-4FBA-B0BDA63560FECEFF.html

In OnTap 8.0, when UNIX security style is selected, only UNIX security objects can be used. The correct answer is GID, UID and UNIX permissions.

Basic UNIX permissions are organized into three classes: user, group, and others.

UNIX operating systems identify users with a numerical value: a user identifier, also known as a UID or User ID. Each user is a member of a group of the same name as the user. Like UIDs, groups (GIDs) are also specified using a numerical value.

The pktt command controls a simple on-filer packet tracing facility. Packets can be captured into a trace buffer then dumped to a file, or the captured data can be logged to a file. The data is stored in "tcpdump" format, and can be directly viewed with tcpdump, ethereal, and perhaps other viewers. The output can also be converted using the editcap(1) program to a variety of other formats, including Sniffer, NetMon, and snoop.

All data, whether file or block-based, resides in 4KB blocks on disk. A group of related blocks make up a file. To accommodate different file sizes, the WAFL filesystem describes each file with reference pointers called inodes.

https://communities.netapp.com/servlet/JiveServlet/previewBody/5027-102-1-6953/PS%20Tech%20Note%20018%20-%20maxfiles.pdf