dmx architecure level questions

8/12/2019 DMX Architecure Level Questions

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DMX Architecure level questions

1. Can you explain about DMX Architecture?The Symmetrix DMX features a high-performance, Direct Matrix Architecture (DMX)supporting up to 128 point-to-point serial connections. Symmetrix DMX technology isdistributed across all channel directors, disk directors, and global memory directors insymmetrix DMX systems.

1. Can you briefly explain about symmetrix series products?Symmetrix 8000/4 was the first symmetrix to introduce a dual bus arcitecture,providing redundancy in the path to memory.

Symmetrix DMX800 is an incrementally scalable, high-end storage array whichfeatures modular disk array enclosures.

Symmetrix Direct Matrix Architecture is storage array technology that employs amatrix of dedicated serial point-to-point connections instead of traditional buses orswitches.

Symmetrix DMX2 is a channel director specification for the DMX with fasterprocessors and newer components.

Symmetrix DMX-3 and DMX-4 are the latest technology using redundant globalmemory and largest capacity.

1. Can you explain Enginuity release code 5773.79.58?57 represents the DMX3/4 Hardware

73 represents the microcode family

79 represents the field release level to the microcode

58 represents the field release to the service processor code


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52 =Symm4, 55 =Symm5, 56 =DMX/DMX2, 57 =DMX3/4, 58 =VMAX.

1. How many Cache directors, Front-end directors and Back-end directors we canuse in DMX-4?

Cache Directors = 4 Min to 8 Max.

Front-end Directors = up to 12 max

Back-end Directors = 6 Min to 8 Max

1. What are the different types of Front-end directors and the purpose of each one?ESCON (EA) : for mainframe attachment and SRDF family links

FICON (EF) : provides the industrys highest performance connectivity

Option for the mainframe.

Fibre (FA/DA) : Connectivity option for open systems direct and SAN

Attachment, and can be used for SRDF family remote

Replication links.

iSCSI (SE) : Provides the industrys first high-end Iscsi Implementation.

GigE (RE) : for SRDF family replication with compression support.

1. Explain Rule 17 in DMX?Possible answers:

1. Rule of 17 ensured that FAs being used for host connectivity were indifferent power zones.

2. The rule of 17 is simply a way to make sure that the paths you connectyour host to are not running on the same director, but one physically faraway from it.

3. The original Rule of 17 was put into place to ensure that there was a pathon each bus (odd and even).The bus architecture went away in DMX-1 (

Symm6). But we had 2 power zones; one zone for directors 1-8, and anotherzone for directors 9-16. So the Rule of 17 still had value.


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4. but DIR 3 (odd) and DIR 4 (even) reside on different buses yet in thesame power zone, so even if you had your host connected to 3 and 4 ..ifthat power zone went down ..Your hosts went down.

1. What are the Management Tools for DMX?Symcli (Symmetrix Command Line Interface)

SMC (Symmetrix Management Console)

ECC (EMC Control Center)

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What are the Enginuity Operational Layes?

Symmetrix Based Application

Host Based Symmetrix Application

Independent Software vendor application

EMC Solutions Enabler API

Symmetrix Enginuity Operating Environment Functions

Symmetrix Hardware

1. What are the major components of System Bay and Storage Bay in DMX?System Bay Components

Either six or eight disk directors and up to 12 channel directors(Combined total = 16).

From four to eight global memory directors. Up to eight power supplies, each of having a dedicated Battery Back Up(BBU) 1U service processor with KVM (keyboard, video screen and mouse) and

dedicated UPS. Three cooling fan assemblies (each containing 3 fans).

Storage Bay Components

120 or 240 disk drives per storage bay

Each Drive Enclosure (DE) includes:


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Two link control cards (LCC).

Redundant power supplies with BBUs to provide standby power.

The DMX-4 storage bay has 2N power zones with independent power cables, eachzone capable of powering the fully configured storage bay.

The storage bay can be populated with various combinations of currentlyavailable DMX one-inch low-profile 4 Gb/s Fibre Channel disk drives available in:

73 GB, 146 GB, 300 GB, and 400 GB Fibre Channel drives

73 GB and 146 GB Flash drives

500 GB and 1 TB SATA II disk drives

1. Can you explain about Read Hit, Read Miss and Fast Write and Delayed Write?Read Hit: In a read hit operation, the requested data resides in global memory. Thechannel director transfers the requested data through the channel interface to thehost and updates the global memory directory. Since the data is in global memory,there are no mechanical delays due to seek and latency.

Read Miss: In a read miss operation, the requested data is not in global memory andmust be retrieved from a disk device. While the channel director creates space in theglobal memory, the disk director reads the data from the disk device. The diskdirector stores the data in global memory and updates the directory table. The

channel director then reconnects with the host and transfers the data. because thedata is not in global memory, the symmetrix system must search for data on the diskand then transfer it to the channel adding seek and latency times to the operation.

Fast Write A fast write occurs when the percentage of modified data in globalmemory is less than the fast write threshold. On a host write command, the channeldirector places the incoming blocks directly into global memory. For fast writeoperations, the channel director stores the data in global memory and sends a

channel end and device end to the host computer. The disk director then

asynchronously destages the data from global memory to the disk device.

Delayed Fast Write: A delayed fast write occurs only when the fast write thresholdhas been exceeded. That is the percentage of global memory containing modifieddata is higher than the fast write threshold. If this situation occurs, the symmetrixsystem disconnects the channel directors from the channels. The disk director thende-stages the data to disk. When sufficient global memory space is available. Thechannel directors reconnect to their channels and process the fast I/O requires as afast write. The symmectrix system continues to process read operations duringdelayed fast writes with sufficient global memory present, this type of global memoryoperation rarely occurs.


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Storage Provisioning questions:

1. How do you calculate number of cylinders for 120 GB LUN?

Maximum device sizes by Enginuity versionEnginuity version MBs CYLs GBsEnginuity 5874 245760 262668 240Enginuity 5773 and earlier 61425 65520 59

Since DMX-4 supports maximum of 60GB hyper size, we have to create two hypersand form a Meta devices as 120GB LUN.

To calculate cylinders for 60GB LUN use the below formula

Cylinders = 60GB/15 tracks* 8 sectors* 16 blocks * 512 bytes

Cylinders = 60000000000/15*8*16*512

Cylinders = 60000000000/983040

Cylinders = 61035 cyl

To calculate the number of cylinders (for pre-Symmetrix DMX), use either of thefollowing: blocks 960 or (size in megabytes) x 2.1333

To calculate the number of cylinders (for Symmetrix DMX and Symmetrix V-Max arrays),use the following: 1 cylinder = 15 tracks; each track is 64 KB, 15 x 64 tracks = .937 MBfor each cylinder

1. What is the maximum hyper size in DMX-4?Maximum Cylinders = 65520

Maximum Capacity = 59GB or 61425 MB


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1. How many hypers can create in a Single disk in DMX4?255 hypers per disk.

1. How many members can contain in one Meta?1 Meta head + 255 members

1. How many LUN IDs available per FA port?256 LUN IDs are available per FA port, 255 LUN IDs are usable out of 256.

1. What is Dynamic LUN addressing?This feature will automatically selects and assigns the LUN IDs to the devices whiledevice mapping to the port Instead of manually assigning address to the device whilemapping

1. How do you add a new member to the existing Meta?

add devXXXX to metaXXXX, protect_data=TRUE, bcv_meta_head=XXXX;or for multiple ranges:

add devXXX1:XXX6to metaXXXX, protect_data=TRUE, bcv_meta_head=XXXX;

1. What is stripping and what is Concatenating?

Stripped Meta Devices

Meta device addressing by striping divides each Meta member device into a series ofstripes, addressing a stripe from each device before advancing to the next stripe onthe first device. When writing to a striped volume, equal size stripes of data fromeach participating drive are written alternately to each member of the set.

Concatenated Meta Devices


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Concatenated devices are volume sets that are organized with the first byte of dataat the beginning of the first device. Addressing continues to the end of the firstdevice before any data on the next device is referenced. When writing to aconcatenated device, the first meta device member receives all the data until it isfull, and then data is directed to the next member and so on

1. What are the DMX-4 supported disk types, no. of disks and maximum capacity?FC drives, iSCSI drives and Flash drives

15 drives per DAE

120 drivers per Cage

240 drives per Storage Bay

2400 drives per array If total of 10 storage bays connected

Maximum storage capacity is 1 PB.

1. Briefly explain the DMX-4 supported Device types?Standard Devices: A Symmetrix device configured for normal Symmetrix operationunder a desired protection method (such as RAID-1,RAID-S, and SRDF).

Gatekeeper Devices:SCSI commands executed by SYMAPI are transferred to theSymmetrix array via a Symmetrix device that is designated as a Gatekeeper device.The gatekeeper allows you to retrieve configuration and status information from theSymmetrix array without interfering with normal device I/O operations.

Meta Devices: Allow individual devices to be concatenated to create larger devices.

BCV Devices: Specialized devices used to create a local copy of data contained in astandard Symmetrix device, which can be used for backup, restore, decision support,and application testing.

SRDF Devices (R1, R2 and R21)Devices configured as RDF1 or RDF2 to supportSRDF operations.

R1 is source device for SRDF operations

R2 is target device for SRDF operations

R21 is used for multi hop SRDF operations

Virtual Devices: A host-accessible device containing track-level location information(pointers), which indicates where the copy session data is located in the physical

storage. Device copies use virtual devices to support TimeFinder/Snap operations.Virtual devices consume minimal physical disk storage, as they store only theaddress pointers to the data stored on the source device or a pool of save devices.,


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Save Devices: Special devices (not mapped to the host) that provide physicalstorage space for pre-update images or changed tracks during a virtual copy sessionof TimeFinder/Snap operations.

Device Masking (VCM)Devices: Symmetrix devices that have been masked forvisibility to certain hosts. The device masking database (VCMDB) holds devicemasking records and typically resides on a 24 or 48 cylinder disk device..

DRV Devices: A non-user-addressable Symmetrix device used by the SymmetrixOptimizer to temporarily hold user data while reorganization of the devices is beingexecuted. Typically, it is used by the Optimizer in logical volume swappingoperations.

1. What is Vault drives and Hot Spare?Vault Drivers: At the time of emergency shutdown of an Array, what ever the data incache memory will be destaged/saved on temporary drives called vault drives

Hot Spare: At the time of physical drive failure hot spare drives will take place

1. What is Preview, Prepare and Commit while using Symconfigure command? The previewargument verifies the syntax and correctness of each individualchange defined, and then terminates the session without change execution.

The prepareargument performs the preview checks and also verifies theappropriateness of the resulting configuration definition against the current stateof the Symmetrix array; the argument then terminates the session withoutchange execution

The commitargument completes all stages and executes the changes in thespecified Symmetrix array

1. What are the possible device service states and device status states?Device Service States : Normal, Failed and Degraded

Device Status States : Ready, Not Ready and Write Disable.


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1. How do you reserve the devices?Symconfigure -sid XXXX -f createdev.cmd expire expiration date-owner myself -comment "this devices are reserved for SRDF activity" reserve

1. How do you create the Disk GroupsWe can not create Disk Groups, It should be done by changing BIN file by CE.

We can rename the existing disk groups.

Example: symconfigure -sid 207 cmd set disk_group 4 disk_group_name =flash_dsks; -v -nop commit

1. How do you check the free space by Disk group and Array as whole?By Disk Group : Symdisk sid XXXX list by_diskgroup

Array as whole : Symconfigure sid XXXX list -freespace

1. How do you check the total assigned devices to a particular Host?Symmaskdb sid XXXX list devs wwn host hba wwn

1. How do you check the total allocated storage of a particular Host?Symmaskdb sid XXXX list capacity Host hostname

1. What is pre check list to assign storage to the host?

1. Verify the available free space in the symmetrix arraySymconfigure -sid SymmID [-v | -freespace [-units cylinders | MB]] list or

symdisk sid 4282 list disk_group GroupNumber

1. Verify the Symmetrix statusSymconfigure sid 4282 verify


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1. If any hung activities found abortSymconfigure sid 4282 abort

1. Explain step by step procedure to provide storage to the Host?o Creating STD deviceo Meta Device Creationo Mappingo Masking

Example:

1. Create a commandfile with the following entry to create hypers.

Create dev count=8, size=12394, emulation=FBA, config=2-way-mir,disk_group=2;

2. Execute the command file using symconfigure command with preview, prepare andcommit options.

Symconfigure sid 4282 f Commandfile.txt v noprompt commit

3. Verify the newly created devices

Symdev sid 4282 list noport

4. Create a commandfile with following entry to form metas and devices to the meta

head.

Form meta from dev 26CA, config=striped, stripe_size=1920;

add dev 26CB:26E4 to meta 26ca;

1. Execute the command file using symconfigure command with preview, prepareand commit options.


1. Verify the newly created meta devicesSymdev sid 4282 list -noport

1. Find the host connected Director and Port details

symcfg sid 4282 list -connections


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1. Find the available addresses on that portSymcfg sid 4282 list address available dir 7d p 0

9. Create a commandfile with the following entry to map the device to the FA port

map dev 26ca to dir 7d:0, lun=036;

1. Execute the commandfile using symconfigure with the preview, prepare andcommit options.


1. Mask the devices to the host HBA and refresh the sym configurationsymmaskdb sid 4282 wwn 10000000c93f62cf dir 7d p 0 add devs 26ca nop

Symmask sid 4282 refresh

12.Rescan the disks and refresh the powerpath or reboot the server to get the

assigned devices at host-end

1. How do you check particular device geometry?Symdev sid XXX show dev SymmDev

1. How do you check the particular device is connected to which Host?Symmaskdb sid XXXX list assignment dev SymmDev

1. What are the steps for storage reclamation? Unmasking Write Disable Un-mapping Dissolve meta Deleting hypers

1. Unmasking devices from the host

symmaskdbsid 4282

wwn 10000000c93f62cf

dir 7d

p 0 remove devs 26ca


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2. Refresh the Symmetrix Array

Symmask sid 4282 refresh

3. Write Disable the devices before unmapping from the Director port

symdev -sid 4282 write_disable 26ca -sa 7d -p 0 -noprompt

4. Create a cmd/txt file

Unmap dev 26ca from dir all:all;

5. Perform preview operation using symconfigure command

Symconfigure sid 4282 f unmap.txt v nop preview

6. Perform prepare operation using symconfigure command

Symconfigure sid 4282 f unmap.txt v nop prepare

7. Perform Commit operation using symconfigure command

Symconfigure sid 4282 f unmap.txt v nop commit

8. Verify that the device has been unmapped

Symdev sid 4282 list -noport

9. To Dissolve meta, create a cmd/txt file

Dissolve meta dev 26ca;



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Symconfigure sid 4282 f dissolve.txt v nop preview


Symconfigure sid 4282 f dissolve.txt v nop prepare


Symconfigure sid 4282 f dissolve.txt v nop commit

13. Verify that the meta has been Dissoved.

Symdev sid 4282 list noport

14. To delete the hypers create a cmd/txt file.

Delete dev 26ca;


Symconfigure sid 4282 f dissolve.txt v nop preview


Symconfigure sid 4282 f dissolve.txt v nop prepare


Symconfigure sid 4282 f dissolve.txt v nop commit

18. Verify that Hypers have been deleted.

Symdev sid 4282 list -noport


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1. How many mirror positions RAID-1 and RAID-5 will occupy?RAID-1 occupies 2 mirror positions

RAID-5 occupies 2 mirror positions

1. How do you convert the concatenating meta device to stripped meta?convert meta XXXX, config=striped, stripe_size=1920, protect_data=TRUE,bcv_meta_head=XXXX;

1. Host is unable to see the storage, how do you troubleshoot?1.

Check that the host is logged in to the Array

Symmask sid XXXX list -logins

1. Check that the cable connectivity status by logging in to the host2. Check that the HBA drivers are properly configured3. Check the Zoning table by logging in to the switch4. Check that the devices status in Array5. Check the VCMDB for masking information, etc..

1. What is Thin Provisioning?Thin provisioning is a method of optimizing the efficiency with which the availablespace is utilized in storage area networks. Thin provisioning operates by allocatingdisk space in a flexible manner among multiple users, based on the minimum spacerequired by each user at any given time.

1. How do you create thin pools and thin devices?Creating Thin Pools

Creating Data devs and added these Data devs to Thin Pools

Creating TDEVs and bind these TDEVs to Thin Pool

Assign TDEVs to host.

1. Explain step by step procedure to setup new host?Let us assume cable connectivity is done properly


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1. Install HBA drivers in host.2. Install Power path if required.3. Check that the HBA ports are showing online4. Create zoning at switch end.5. Check that this host is logged in to the Storage array6. Create LUN/hypers in storage array7. Form meta devices if required8. Map the devices to the FA port.9. Mask the devices to the host hba (wwn).10.Refresh the Array to affect the changes.

Symmetrix Environment familiarity questions

1. How do you check the failed components in Symmetrix Array?Symcfg -sid 150 list -env_data -service_state failed

1. How do you check the failed disks in the Symmetrix Array?Symdisk sid XXXX list -failed

1. What is the purpose of Gate Keeper device?Low-level I/O commands executed using SYMCLI are routed to the Symmetrix arrayby a Symmetrix storage device that is specified as a gatekeeper.

The gatekeeper device allows SYMCLI commands to retrieve configuration and statusinformation from the Symmetrix array without interfering with normal Symmetrixoperations.

The gatekeeper must be accessible from the host where the commands are beingexecuted.

1. How many gate keeper devices are required per Array?It depends on the Symmetrix management applications using in management

servers,


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As per EMC recommendations 6 gatekeepers are required per management hostusing symcli

1. How to list hosts and their EMC registered software, using Solutions Enabler?Symcfg sid XXXX list -applications

1. What is VCMDB and how do you take the backup?The device masking database (VCMDB) holds device masking records and typicallyresides on a 24 or 48 cylinder disk device..

Symmaskdb sid XXXX backup f filename

1. How do you list the Hosts which are connected to particular director port?Symmaskdb sid XXXX list database dir XX p X

1. How do you check the number of storage bays connected to the system bay andnumber of disks in each storage bay?

Symcfg sid XXXX list env_data

1. How do check the devices which are not mapped and masked?Symdev sid 4282 list dev -noport

1. How do you check the devices which are mapped to FA but not masked to anyhost?

Symmaskdb -sid 123 list no_assignment -dir ALL -p ALL

1. How do you check the login hosts in the Symmetrix Array?Symmask sid 4282 list logins


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1. How to display and set the Symmetrix metrics?Symcfg sd XXXX SA all list v

Set Symmetrix MatricName=MatricValue

1. How do you check the configured environmental variables?Symcli -def

1. Can windows, Linux, Solaris share the same FA in DMX?Yes, if they share the same port flags

1. What are the Symmetrix External locks and how to check and release?Symmetrix external locks are used by SYMAPI (locks 0 to 15) and also for

applications assigned by EMC (>15) to lock access to the entire Symmetrix array

during critical operations

We can check the external locks by giving the below command

symcfg sid XXXX list -lockn

We can check the external locks by giving the below command

symcfg release -sid -lockn 15 force

Symmetrix Performance Monitoring questions

1. How to monitor performance of EMC Symmetrix?1. Using Performance Monitoring feature in EMC Control Center2. Using SYMSTAT symcli command


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1. How do you check the cache activity of front-end directory?Symstat sid 4282 -type cache -i 5 -c 4 -sa all

1. How do you check the I/O requests and throughput of selected disk?Symstat sid 4282 -type disk -i 5 -c 3 -disk 2a,C,5

1. What are the available performance types in SYMSTAT command?

REQUESTS: Reports I/O requests and throughput for selected devices, directors, orSRDF/A sessions. (This is the default type; if no type is specifiedREQUESTS is used.)

BACKEND: Reports back-end I/O requests and throughput for selected devices.

PORT: Reports performance statistics for a director port. ISCSI Report Gig-E

network statistics.

CACHE: Reports cache activity for selected front-end or remote link directors, or SRDF/Asessions.

MEMIO: Reports cache memory to disk activity for selected devices. PATH Report R-Copypath information for nonincremental sessions. Symmetrix arrays that haveall or some incremental sessions will report an error.

CYCLE: Report cycle summary information for SRDF-A sessions.

DISK: Reports back-end I/O requests and throughput for selected disks.


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PREFETCH: Reports track prefetch disk activity for selected back-end directorsonly.DMSP Reports dynamic mirroring service policy (DMSP) statistics forthe selected device(s).

RDF: Reports SRDF statistics from the perspective of RA groups, devices, or directors.

1. What is symmetrix optimizer and how it works?Symmetrix Optimizer improves array performance by continuously monitoring accesspatterns and migrating devices (Symmetrix logical volumes) to achieve balanceacross the disks in the array

Step 1: Symmetrix Optimizer builds a database of device activity statistics on theSymmetrix back-end.

Step 2: Using the statistical data collected, configuration information, and the

user-defined parameters, the Optimizer algorithm identifies busy and idle devices

and their locations on the physical drives. The algorithm tries to minimize averagedisk service time by balancing I/O activity across physical disks. Optimizerdetermines which disks require balancing by locating busy devices close to each

other on the same disk, and/or by locating busy devices on faster disks or fasterareas of the disks. Optimizer takes into account the speed of the disk, the diskgeometry, and the actuator speed to determine faster disks.

Step 3: Once a solution for load balancing has been developed, the next phase is tocarry out the Symmetrix device swaps. This is done using established TimeFindertechnology, which maintains data protection and availability. we can specify whetherswaps should occur in a completely automated fashion, or if the device swaps requireuser approval before the action is taken.

Step 4: Once a swap function completes, Symmetrix Optimizer continues data

analysis for the next swap.

1. What is Symmetrix QoS and how it works?Quality of Service (QoS) allows more flexibility in managing Symmetrix

systems performance. By increasing the response time for specific copy operations

on selected devices, we can increase the overall performance of the other Symmetrixdevices.


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The QoS (Quality of Service) feature allows us to adjust the data transfer pace onspecified devices, or devices in a device group, for certain operations.

The contention for cache access can be quality of service managed by the least

recently used (LRU) ring partitions in the Symmetrix cache.

We can control the priority service time of devices and control cache partitions fordifferent device groupings.

1.

What is the purpose of Symmetrix Change Tracker?

To measure changes to data on a Symmetrix volume or group of volumes.

Change Tracker data is often used to analyze and design TimeFinder and SymmetrixRemote Data Facility (SRDF) configurations.

Change Tracker (DeltaMark) session must be created using the symchg createcommand. The symchg mark command is then used to perform a timestamp andmark the selected area of disk storage occupied by a data object using a DeltaMarkbitmap

1. What is Dynamic Cache Partitioning?A QoS feature, dynamic cache partitioning allows the Administrator the means to

dynamically control the cache area size, servicing a given device group I/O, by

defining flexible partitions through cache memory.

Dynamic Cache Partitioning divides the cache memory into multiple partitions withunique names and their device path assignments.

Partition areas can be made static or dynamic in size. The dynamic partitioning

provides flexibility to the amount of floating memory that can be allocated with a


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high and low watermark. This allows memory resources to be temporarily donated toother partitions when needed.

The symqos command allows you to create partitions for different device groupingsin addition to the default partition that all devices belong to initially. Each partitionwill have a target cache percentage as well as a minimum and maximum percentage.In addition, you can donate unused cache to other partitions after a specifieddonation time.

1. What are the logs available at host-end and on symmetrix array?1. Host end logs are available in Symapi\log folder2. Event logs and Audit logs in symmetrix array

1. How do you monitor the real time events on symmetrix array with example?1. To monitor real time 100 event records with 600 seconds interval in the

symmetrix array

Symevent -sid 4282 monitor -i 600 -c 100 warn/-error/-fatal

1. How do you track the history of events on symmetrix array with example?1. To list all events in symmetrix arraySymevent -sid 4282 list

1. To list specific period of time events in event logsSymevent -sid 4282 list -v -start 9:00 -end 17:00

1. How do you check the audit logs on symmetrix array?1. To show the details about audit log it self.Symaudit -sid 4282 show

1. To list the audit log records of specific period of time.Symaudit -sid 4282 list -v -start_time 7/11:9:00 -end_time 7/11:10:00

1. To monitor the real time audit logs 100 records with 30sec interval.symaudit -sid 4282 monitor I 30 c 100


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Symmetrix DMX Security related questions:

1. What is Symmetrix ACL?To create access control list on symmetrix array to implement host level or user levelsecurity.

1. Explain step by step to setup the access controls on symmetrix array?1. Create Access GroupCreate a command file with the following entries.

Create accgroup AccessGroupName;

Execute the command file

Symacl sid 4282 commit file commandfile

1. Add host access ID or user access ID to access group.Create a command file with the following entries

Add host accid Id name Idname to accgroup GroupName;

Add user accid Id name Idname to accgroup GroupName;


Symacl sid 4282 file CommandFileName commit

1. Create Access PoolsCreate a command file with the following entries.

Create accpool AccessPoolName;



1. Add devices to the access poolCreate a command file with the following entries.

Add dev StartDevName:EndDevName to accpool AccessPoolName;



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1. Grant Rights to Access GroupsCreate a command file with the following entries.

Grant access=Base/BCV/RDF to accgroup AccessGroupName to accpoolAccessPoolName;



1. How do you take the backup/restore of ACLs?Symacl sid 4282 backup file commandfile

Symacl sid 4282 commit restore f commandfile

1. What is Symmetrix User Authorization?Set up or update the Symmetrix array user authorization information

1. Explain step by step procedure to setup user authorization on symmetrix array?1. User-to-role mappings have to be created.Create a text file with the following entry (rolemap.txt)

Assign user H:Host\username to role Monitor;

Assign user D:Eng\username to role Admin;

Execute the above file

Symauth sid 4282 f rolemap.txt commit.

(Roles: None, Monitor, Storage admin, admin, Auditor, SecurityAdmin)

1. Enable the user authorization.Symauth sid 4282 enable

1. How do you perform backup and restore user authorization information?


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Symauth sid 4282 backup f backupfile.txt commit

Symauth sid 4282 restore f backupfile.txt commit

Solutions Enabler Questions

1. What is the purpose of bin file in SYMAPI database?It is a database file in the host which stores the symmetrix arrays configurationdata. Can be used to get the configuration data offline.

1. What are the services of symcli?1. Storapid : Base daemon2. Storevntd : Asynchronous event daemon3. Storgnsd : Group Name Services support4. Storifmxd : Informix Database support5. storora64d : Oracle Database 64-bit support6. stororad : Oracle Database support7.

storrdfd : RDF consistency support8. storsqld : SQL Server Database support

9. storsrmd : SRM daemon10.storsrmd64 : SRM daemon 64-bit support11.storsrvd : SYMAPI server12.storstpd : Performance collector13.storsybs11d : Sybase 11 database support14.storsybs12.5_64d : Sybase 12.5 (64-bit) database support15.storsybs12.5d : Sybase 12.5 database support16.storsybs12d : Sybase 12 database support17.storudbd : DB/UDB support18.storwatchd : Watchdog daemon

1. Briefly explain about Symcli Base Management Commands?Symacl : Sets up or updates Symmetrix Access Control information.

Symaudit : Allows records to be extracted from a Symmetrix audit log file to


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determine which application on which host initiated actions that directedSymmetrix array behavior. In addition, it provides the ability to determinethe date, time, and size of the current log file.

Symauth : Allows set up or updates to the Symmetrix array User Authorization

information

Symbcv : Performs support operations on one or more Symmetrix BCV

(Business Continuance Volume) devices.

Symcfg : Discovers or displays Symmetrix configuration information. Refreshes

the host's Symmetrix database file or removes Symmetrix informationfrom the database file. Rebuilds the set of devices known to the local host.It can also be used to view or release a hanging Symmetrix exclusive lock,

online or offline RDF (RA), or front-end (SA or FA) director ports.

Symcg : Performs operations on a Symmetrix RDF composite group (cg).

Symcli : Provides a brief description of all the commands included in the

Symmetrix Command Line Interface (SYMCLI) and the environmentvariables.

Symdev : Displays information for the selected, or all, Symmetrix devices.

Symdg : Performs operations on a Symmetrix device group.

Symdisk : Reports on the configuration and status of disks and their hypers

within Symmetrix arrays.`

Symdrv : Displays information for selected DRV devices.

Symevent : Enables the monitoring and tracking of events on Symmetrix arrays.

Symgate : Performs support operations on a gatekeeper device.

Syminq : Issues a SCSI INQUIRY command, and optionally a SCSI READ

CAPACITY command, on one or all devices. In addition, it can be used toobtain a list of the local host's HBAs.

Symlabel : Performs device label (signature) support operations on devices in a

device group.

Symld : Performs operations on one or more standard devices (STD) or

virtual devices (VDEV) in a device group (dg).


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Sympd : Displays information about one or all Symmetrix devices that are

visible to your host.

Symqos : Provides Quality of Service (QOS) controls on specified devices.

Symreturn : Indicates a return value within pre-action and post-action scripts.

Symsg : Performs operations on storage groups located in a specified

Symmetrix array.

Symstat : Displays statistics information about a Symmetrix array, any or all

directors, a device group, a disk, or a device.

1. How do you prepare the Storage Capacity planning reports by host wise?1. By using EMC Control Center2. By using symcli commands symcfg and symdiskSymcfg sid 4282 list connections capacity

Copy and past the output of the above command in excel file and formataccording to the requirement.

Or

Symdisk sid 4282 list -by_diskgroup

Copy and past the output of the above command in excel file and do

the format according to the requirement.

1. By using what symcli command we can check the HBA details?Syminq hba fibre

1. What are the business continuity tools for symmetrix array?1. Power path - host end2. TimeFinder local replication3. SRDF - Remote Replication

dmx architecure level questions

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