1 Have you ever involved in performance issue & how do you verify

it ?
* If an application or database has performance issues, we first Check server, storage,
and SAN switch ports for problems

Analyze IOPS (input/output operations per second) and storage (LUN) response time

If we find any issues, we suggest moving to better storage for improved performance.

2 Will you create Volume or lun First in netapp?

* Create volume with 10% Extra space from the aggregate

Create the lun from the respective volume.

3 Can we create multiple luns on single volume?

* Yes, we can create multiple luns from the single volume If the volume had enough
space.

But as we will create single lun from the one volume to avoid.

This is because if multiple LUNs share the same volume and the volume goes o line

LUNs on the volume will be o line.

4) There is enoguh free space in NAS volume/folder but unable to

write the data what is the issue?
Ans) There might be no.of Inodes become full hence unable to write the new data even
we had free space

5) How many switches max we can have in fabric

Ans) 239 switches
6) How do you check inode value ?
Ans) Using df -h command in storage CLI, we can check total inodes, used and free
inodes and volume size as well

7 What is max size we can write in NAS folder/directory

Ans) we can use upto 320MB then have to go for new folder/directory

8) How many switches in fabric in your environment

Ans) We have 4 di erent fabrics.
In some fabrics, there are 3 switches, while in others, there are 2 switches.

9 How the switches connect each other in Fabric

Ans) Previously, we used the ISL (Inter-Switch Link), and

now we are using the ICL (Inter-Chassis Link).

10) How do we fix the errors

ans) Either reset the FC cable or replace the FC cable and SFP at SAN switch end and
check end to end FC cable

11 How to check the errors in san switch and what are the errors
Ans Using porterrshow Command:

 Checks for errors like:

CRC , PCS ,Timeout, Link resets, Signal errors

12 If we had any issue in the produciton ? how do we get data

safe?
Ans) To keep data safe in production Replicate data from PROD to DR using ODG.

In case of PROD issues, switch over the database to DR.

13) If we loss the data in produciton? how to we get back it
* If data is lost in production, we recover it from the latest backup with the help ofthe
backup team.

If backups are unavailable, we restore the data from the DR (Disaster Recovery) site, as
backups are

typically initiated from DR to avoid performance impact on production.

14) The user want to assign 100Gb or any size of the lun, please tell
me the process
Ans To set up a 100GB LUN, first verify or configure zoning for the server. Then, create
the LUN in the storage system, map it to the host, rescan the disk on the host, initialize
it, and mount it for use.

15 Have you ever involed in performnace issue and how do you

verify it?
Ans) We check for performane issue in application or Data bases by verifying server
and storage port status san switch

We also Check LUN IOPS and response time;

if any abnormalities are found, we recommend migrating to better storage.

16 what are the parameters will verify for the respective lun for
performance issue ?
Ans) luns IOPS, server and storage ports error status at san switch end any path
failures

17 What is the processor in san switch.

its controls data flow and manages switch operations.

18 How many blades for the switch: min 1 and max 12

19 Have you done any firmware upgrade for Storage & san
switches ?
A) Yes, firmware upgrades both storage systems and SAN switches.

first of all, we should recommend firmware code and store in ftp server

Run the firmware download command:

Enter the FTP server details: username and password choose the firmware File from
FTP server and upgrade will start in the background and it will take 15 to 30 minutes

Coordinate with the vendor support for firmware upgrade. Address bugs,

improve performance, and add new features, security issues

Storage System may include updating controllers, disks, and RAID firmware.

SAN switch upgrades focus on OS (Brocade) or NX-OS (Cisco).

Always back up configs, check compatibility,

20 What is the difference between SAN & NAS

(Storage Area Network) (Network Attached Storage)

Feature SAN (Block Storage) NAS (File Storage)

Acts Like Hard disk to server Shared folder

Speed Faster Slower

Use Case Databases, VMs File sharing, backups

Setup Complex Simple

Cost Expensive Cheaper

21 Port Speed
How fast data moves through the SAN port (e.g., 1 Gbps, 2 Gbps, 4 Gbps, 8 Gbps, 16
Gbps, 32 Gbps).

Higher speeds = faster data transfer between devices.

22 What is the index node in NAS volume
An index node is a data structure in Unix-like file systems (ext3, ext4, etc.).

Used in NAS with Linux-based file systems.

Inode stores:

File size, permissions, owner , Timestamps (created, modified, accessed)

23 What is the principal switch?

Main switch in a Fibre Channel SAN.

Manages Domain ID assignment ( switch has a unique ID).

Organizes and connects the fabric.

Elected automatically (based on lowest WWN).

Needed when: Adding a new switch > Merging fabrics > Troubleshooting SAN issues

24 What is the zoning and which zoning you prepared in

environment?
Ans What is Zoning : Controls which devices can communicate in a SAN.

Improves security, performance, and isolation

Types of Zoning : Based on switch port numbers.

Based on device WWNs (unique IDs)

Zoning Used in Environment:

Created zones with Host WWN ↔ Storage WWN

Added zones to a zone set and activated it

25) How to integrate the vmware cluster with storage and zoning ?
To connect storage to a VMware cluster, first get the WWN numbers from each ESXi

host. on the SAN switch, create zones to connect each host to the storage ports activate
the zone set. On the storage system (e.g., NetApp or EMC),

create LUNs and give access to the hosts WWNs

Rescan storage on each ESXi host so they can see the LUNs.

Format the LUNs with VMFS to create shared datastores.

26) How to assign the space for VMware base cluster?

Set up storage by creating a LUN or NFS

share and connecting it to your ESXi hosts via iSCSI, FC, or NFS.

Login to vSphere Client → Go to Storage → New Datastore.

Select datastore type (VMFS / NFS / vSAN) and complete the wizard.

Ensure all ESXi hosts can access the datastore, then use it to deploy and store virtual
machines.

27 How to do zoning for the esxi base cluster ?

Collect WWPNs of ESXi host HBAs and storage FC ports.

Login to SAN switch (Brocade/Cisco) using CLI or GUI.

Create aliases to identification of WWPNs.

Create zones pairing each ESXi HBA with the target storage port.

Add zones to a zone set (group of zones).

Activate the zone set on the SAN switch.

Rescan storage adapters in ESXi to detect the storage LUNs.

28 Have you done any dr drills ?
They are very important to keep business running during unexpected problems like
system crashes, natural disasters, or cyberattacks.

Switch to backup systems or data centres

Restore data and verify backups

Measure recovery time (RTO)

Check data loss tolerance (RPO)

29 Explain the Zoning steps ?

You’ve created a safe and private connection between a server and storage.

Get the unique ID numbers (WWNs) of: Your server’s port && storage’s port

easy names like: My Server && My Storage

Create a Zone : My Server && My Storage

A Zone Set is like a group of all your zones.

30 what is the difference between Lun masking and Lun mapping ?

Feature LUN Mapping LUNMasking

Purpose Makes LUN available via port Restricts which hosts can

access the LUN.

Works on Storage array Storage array or HBA.

Visibility LUN becomes visible on the port LUN becomes visible

only to selected hosts.

Security Not secure on its own Adds access control

31 What is LUN Expansion?
LUN Expansion means increasing the size of an existing LUN (Logical Unit Number) so
that your server or application

gets more storage space — without deleting or recreating the LUN.

You’re running out of disk space

You want to avoid downtime

You don’t want to lose any existing data

32 How do we verify enough free space in the pool ?

To verify if there is enough free space in a storage pool, the approach depends on the
underlying storage system.

ZFS (Zettabyte File System): Use zpool list to check total size, allocated, and free
space.

LVM (Logical Volume Manager): Use vgs to check free physical extents (PE) and
available size in the

Traditional Filesystems (ext4, xfs, etc.): Use the df -h command to check free space on
mounted filesystems

33 what stpes to follow check performance issue ?

Monitor System Resources:

Use tools like top, iostat, vmstat, or cloud monitoring to check CPU, memory, disk, and
network usage.

Check Application & Database Logs:

Analyze logs for slow queries, exceptions, or resource bottlenecks.

Identify Root Cause & Fix:

Correlate metrics and logs to identify the issue, apply the fix, and then monitor the
system to ensure that performance is restored.
34 What is the RTO and RPO ?
RTO is the maximum acceptable time to recover a service after a failure.

RPO is the maximum acceptable data loss in time during a disruption.

If RTO is 2 hours and RPO is 15 minutes, the system must be restored within 2 hours
with no more than 15 minutes of data loss.

35 What is ISL (Inter-Switch Link):

A connection between two SAN switches.

Expands the fabric for communication between devices.

Carries data and management tra ic.

36 What is ICL (Inter-Chassis Link):

A special connection between two SAN switch chassis (like Brocade Directors).

Faster than normal ISL.

Saves ports and gives better performance.

37 Port type like F Port, G Port, E Port.

F Port: Connects devices (servers, storage) to the SAN fabric.

G Port: Can function as either F Port or E Port based on connection.

E Port: Connects two switches to expand the fabric.

38 Set Npiv and limit

NPIV (N_Port ID Virtualization):

Allow multiple virtual ports on one physical port. Each virtual port has a unique ID.

Limit : Sets the maximum number of virtual N_ports or devices that can be supported.
Tools & Technologies:

Storage Management Tools: Unisphere, System Manger

Storage Arrays: IBM SVC, V7000, DELL EMC UNITY XT380

Switches: Brocade 5100, DCX8510-8.

Switch operations: Zoning, Monitoring

🔧 Storage Management Tools

1. Unisphere

Vendor: Dell EMC (Electromagnetic Compatibility)

Used for: Managing VNX, Unity, and PowerMax storage systems.

Features:

Web-based GUI for easy navigation.

Storage provisioning and performance monitoring.

Health alerts and troubleshooting

Centralized management of multiple storage arrays.

2. System Manager

Vendor: NetApp ( ONTAP System Manager)

Used for: Managing NetApp based systems.

Features:

Simplified GUI for clusters and SVMs (Storage Virtual Machines).

Storage provisioning and snapshot management.

Monitoring performance and capacity.

Role-based access control and automation support.

🗄 Storage Arrays

IBM SVC (SAN Volume Controller)

It is a storage virtualization system . It’s often used in enterprise SANs.

that simplifies management by virtualizing multiple storage arrays

real-time data migration, thin provisioning, compression, replication, and high

availability. Simple and e icient

2. IBM Storwize V7000

It is Hybrid flash storage array designed for mid-range use in physical and virtual
environments.

Supports block and file storage (via Spectrum Virtualize). Combine Flash and HDD
mix with automated tiering. o ers features Thin provisioning, deduplication,
compression. Replication (Metro & Global Mirror) Easy IBM SVC integration

3. Dell EMC Unity XT 380

Mid-range All-Flash or Hybrid storage array. Designed small to medium enterprise

workloads.

supports block, file, and VMware VVols. With a high performance NVMe-ready design

cloud integration for tiering and monitoring (Cloud Tiering, CloudIQ).

Inline data deduplication and compression.

Managed via Unisphere (web UI) and REST APIs.

Switches

Brocade 5100

It is Mid-range Fibre Channel SAN switch (40 × 8 Gbps ports)

It Designed for small to mid-sized SAN environments.

Non-blocking performance on all ports. design Scalable and energy-e icient.

It Supports like zoning, trunking, and advanced diagnostics.

Easy fabric integration for storage expansion.

Brocade DCX 8510-8

Type: Director-class Fibre Channel SAN switch (8-slot, up to 384 ports)

Built for large-scale data centers with mission-critical workloads.

Ultra-low latency and high throughput.

Enterprise-class scalability and reliability.

Fabric Vision, and congestion management.

Supports Gen 5/6 Fibre Channel support. Redundant power, fans, CPs
Switch operations

Zoning

Definition: A SAN security feature used to control and isolate communication between
devices (hosts and storage) with a Fibre Channel fabric.

Allows only authorized devices, improves security, and reduces conflicts.

Soft Zoning: Name server-based access control

Hard Zoning: Switch port-based access control

Common Tools CLI, Web Tools, Brocade Network Advisor

Monitoring

Definition: The continuous observation of SAN health, performance, and faults.

Detect issues early and maintain uptime.

Link Errors: CRC errors , Bu er Credit Shortages, Port Failures

Tools Used: Fabric Vision, CloudIQ, Unisphere, ONTAP System Manager, SNMP traps,
Syslog

Core Responsibilities:

Maintaining SAN environment with 24×7365 support.

Handling storage escalations and break-fix issues.

Managing heterogeneous storage, with focus on EMC VMAX2/3, 40K, and 100K.

Tools & Technologies:

Storage Management Tools: Unisphere, System Manger

Storage Arrays: IBM SVC, V7000,DELL EMC UNITY XT380

Switches: Brocade 5100, DCX8510-8 .

Switch operations: Zoning,Monitoring

Technical Skills & Tasks:

Virtual Provisioning:

Creating Data Devices, Thin Devices & Pools.

Binding Thin Devices to Pools using SymCLI.

Performance Analysis:

Monitoring FA utilization, I/O performance times.

optimizing under-utilized FA pairs and high-latency issues.

Storage Management:

Handling MetaLUN expansion, personality conversion, striped LUN growth via BCVs,
and thin provisioning issues.

Firmware Upgrades:

Performing firmware upgrades for Brocade switches.

Taking regular backups of Brocade fabric configurations.

Issue Management:

Collaborated with EMC for troubleshooting and log collection.

Worked with customer, partner, and Problem Management teams to

resolve long-running performance issues and proactively address SAN-related

problems.

Project Work:

Storage reclamation (orphaned storage).

Re-balancing thin pools.

Re-balancing highly utilized arrays.

Selecting RAID levels for best performance and reliability.

Documentation & Coordination:

Creating/enhancing documentation, coordinating with DC site services for physical

tasks, and maintaining logs

and knowledge base for new issues.

FULL FORMS

RPO Recovery Point Objective

RTO Recovery Time Objective

LUN Logical unit number

WWPN world wide port Name

SAN Storage Area Network

DR Disaster Recovery

ODG Online Data Gathering System

ESXi Elastic Sky X Integrated

VMFS Virtual Machine File System,

HBA Host Bus Adapter

ICL Inter chasis link

SMC Server Management Console

EMC Electromagnetic Compatibility

GUI for Graphical User Interface.

SVC for SAN Volume Controller.

CRC for Cyclic Redundancy Check.