Netapp Hardware Interview Questions and Answers

1. What is NVRAM..?
Ans:- Non-volatile battery-backed memory (NVRAM) is used for write caching.

2. Do you know how data is written to the disk in Netapp.? Please explain..?
Ans:- As soon as the write to NVRAM is confirmed, the storage appliance acknowledges the write as completed to the client machine. At pre-determined triggers, this buffered write data is processed from storage device memory through the Write Anywhere File Layout (WAFL) and RAID layers and written to disk.

3. What is SP/RLM/BMC..?
Ans:- 
SP - Service processor
 SP monitors the system temperatures, voltages, currents, and fan speeds. When an environmental sensor has reached an abnormal condition, the SP logs the abnormal readings, notifies Data ONTAP of the issue, and sends alerts and 'down system' notifications as necessary through an AutoSupport message, regardless of whether the storage system can send AutoSupport messages

RLM - Remote LAN Module 
The RLM provides remote node management capabilities, including remote access, monitoring, troubleshooting, logging, and alerting features

BMC -  Baseboard management console
The AutoSupport settings are used for sending the alerts through e-mail over the BMC LAN interface.

4. What is difference between FAS and V-Series..?
Ans:- 
FAS - Fibre attached Storage
V-Series - Virtualized  Series 

FAS is used in Single node and HA pair configuration
V-Series is used when want to virtualize with third party Storage system

5. What is difference between 7-mode and C-mode..?
Ans:- 
7-mode either single node Or two controllers clustered for HA. Single node will support for single namespace. One controller will work as a single node. 

C-mode either single controller "pair" Or multi controller "pairs" connected as a clustered. Each VServer will work as a single entity. It will support for multi namespaces 

 6. What is the maximum capacity of volume in 7-mode 32bit..?
Ans:- 16TB

7. How many disk types can Netapp support..?
Ans:-   FC, SAS, SSD, Near Line SAS and SATA

8. How to check your Netapp serial number..?
Ans:- sysconfig -a

9. how to determine that FC port is working an which mode..?
Ans:- using fcadmin command we can verify

10. How to verify whether all the disk shelfs for connected in redundant..?
Ans:- sysconfig -d and storage show disk   

Commands Netappp

This post contains the list of commands that will be most used and will come handy when managing or monitoring or troubleshooting a Netapp filer in 7-mode.

• sysconfig -a : shows hardware configuration with more verbose information
• sysconfig -d : shows information of the disk attached to the filer
• version : shows the netapp Ontap OS version.
• uptime : shows the filer uptime
• dns info : this shows the dns resolvers, the no of hits and misses and other info
• nis info : this shows the nis domain name, yp servers etc.
• rdfile : Like “cat” in Linux, used to read contents of text files/
• wrfile : Creates/Overwrites a file.
• aggr status : Shows the aggregate status
• aggr status -r : Shows the raid configuration, reconstruction information of the disks in filer
• aggr show_space : Shows the disk usage of the aggregate, WAFL reserve, overheads etc.
• vol status : Shows the volume information
• vol status -s : Displays the spare disks on the filer
• vol status -f / aggr status -f : Displays the failed disks on the filer
• vol status -r : Shows the raid configuration, reconstruction information of the disks
• df -h : Displays volume disk usage
• df -i : Shows the inode counts of all the volumes
• df -Ah : Shows “df” information of the aggregate
• license : Displays/add/removes license on a netapp filer
• maxfiles : Displays and adds more inodes to a volume
• aggr create <Aggr Name> <Disk Names> : Creates aggregate
• vol create : Creates volume in an aggregate
• vol offline : Offlines a volume
• vol online : Onlines a volume
• vol destroy : Destroys and removes an volume
• vol size [+|-] : Resize a volume in netapp filer
• vol options : Displays/Changes volume options in a netapp filer
• qtree create : Creates qtree
• qtree status : Displays the status of qtrees
• quota on : Enables quota on a netapp filer
• quota off : Disables quota
• quota resize : Resizes quota
• quota report : Reports the quota and usage
• snap list : Displays all snapshots on a volume
• snap create : Create snapshot
• snap sched : Schedule snapshot creation
• snap reserve : Display/set snapshot reserve space in volume
• /etc/exports : File that manages the NFS exports
• rdfile /etc/exports : Read the NFS exports file
• wrfile /etc/exports : Write to NFS exports file
• exportfs -a : Exports all the filesystems listed in /etc/exports
• cifs setup : Setup cifs
• cifs shares : Create/displays cifs shares
• cifs access : Changes access of cifs shares
• lun create : Creates iscsi or fcp luns on a netapp filer
• lun map : Maps lun to an igroup
• lun show : Show all the luns on a filer
• igroup create : Creates netapp igroup
• lun stats : Show lun I/O statistics
• disk show : Shows all the disk on the filer
• disk zero spares : Zeros the spare disks
• disk_fw_update : Upgrades the disk firmware on all disks
• options : Display/Set options on netapp filer
• options nfs : Display/Set NFS options
• options timed : Display/Set NTP options on netapp.
• options autosupport : Display/Set autosupport options
• options cifs : Display/Set cifs options
• options tcp : Display/Set TCP options
• options net : Display/Set network options
• ndmpcopy : Initiates ndmpcopy
• ndmpd status : Displays status of ndmpd
• ndmpd killall : Terminates all the ndmpd processes.
• ifconfig : Displays/Sets IP address on a network/vif interface
• vif create : Creates a VIF (bonding/trunking/teaming)
• vif status : Displays status of a vif
• netstat : Displays network statistics
• sysstat -us 1 : begins a 1 second sample of the filer’s current utilization (crtl – c to end)
• nfsstat : Shows nfs statistics
• nfsstat -l : Displays nfs stats per client
• nfs_hist : Displays nfs historgram
• statit : beings/ends a performance workload sampling [-b starts / -e ends]
• stats : Displays stats for every counter on netapp. Read stats man page for more info
• ifstat : Displays Network interface stats
• qtree stats : displays I/O stats of qtree
• environment : display environment status on shelves and chassis of the filer
• storage show <disk|shelf|adapter> : Shows storage component details
• snapmirror intialize : Initialize a snapmirror relation
• snapmirror update : Manually Update snapmirror relation
• snapmirror resync : Resyns a broken snapmirror
• snapmirror quiesce : Quiesces a snapmirror bond
• snapmirror break : Breakes a snapmirror relation
• snapmirror abort : Abort a running snapmirror
• snapmirror status : Shows snapmirror status
• lock status -h : Displays locks held by filer
• sm_mon : Manage the locks
• storage download shelf : Installs the shelf firmware
• software get : Download the Netapp OS software
• software install : Installs OS
• download : Updates the installed OS
• cf status : Displays cluster status
• cf takeover : Takes over the cluster partner
• cf giveback : Gives back control to the cluster partner
• reboot : Reboots a filer