Creating Protected BCVs Using SYMCLI

 

Topic

Managing TimeFinder

Selections

Select TimeFinder Action: Managing TimeFinder with Solutions Enabler SYMCLI

Select operating system: Windows 2003

Select a task: Managing TimeFinder/Mirror

Select a task: Creating protected BCVs

 

 

.

Contents

·             Creating Protected BCV Devices. 4

·             Establishing BCV Pairs. 6

·             Working with Unprotected BCV Devices. 7

 


 

 

·        Creating Protected BCV Devices 

 

Overview

For higher, safe, data availability, it is recommended that every BCV in your Symmetrix device configuration list be created with mirrored protection. This procedure deals with ensuring that a BCV in your storage array is configured with an additional mirror for optimum data protection.

 

This procedure is based on content from the following EMC manual:

  • EMC Solutions Enabler Symmetrix Array Controls CLI Product Guide

 

You can download the guide from EMC Online Support (registration required): https://support.EMC.com

 

 

 

1.

Look for free space

To check for available free space before you begin, enter the following command:

 

   symconfigure –sid SymmID list –freespace -units CYLINDERS

 

Look for available devices

Examine the Symmetrix configuration for available devices and cylinder sizes by examining the output from a Symmetrix device list. To see all the various devices, enter the following command:

 

symdev list –sid SymmID list –cyl

 

 

2.

About the create device command

To add or create a Symmetrix device, use the following syntax in the command file:

 

create dev count=n, size=Cylinders,

  emulation=EmulationType,

  config=DeviceConfig,

  [, data_member_count=nn]

 

where:

count = The number of devices to create.

 

size = The size of the device needed in number of cylinders. In Symmetrix DMX models, a cylinder of an FBA device contains 1920 512-byte blocks, or .98 megabytes. In earlier Symmetrix models, a cylinder of an FBA device contains 960 512-byte blocks or, .468 megabytes. To calculate the number of cylinders, use either of the following:

 

blocks ÷ 960

or

(device size in megabytes) x 10242 ÷ (960 x 512 bytes)

or

(size in megabytes) x 2.133

 

Note: Devices to be used as BCV, RDF, or metamembers will need to precisely match corresponding device sizes. Use symdev/sympd show or symdev/sympd list –cyl commands to see relevant device sizes.

 

For additional information about sizing devices in cylinders, refer to Chapter 1 of the Solutions Enabler Symmetrix Array Management CLI Product Guide.

 

Emulation = The device emulation type, which currently must be fixed block architecture (FBA), CELERRA FBA, VME512 FBA, or CKD-3380 or CKD-3390 for z/OS environments.

 

 

config = For best practices that provides BCV mirrored protection, the desired device configuration type for this case must be restricted one of the following types:

 

2-Way-BCV-Mir

BCV-R-5

BCV-R-6

 

Note: BCV-R-5 and BCV-R-6 are RAID type BCV devices which will have as much as 4 mirrors for high data availability assurance.

 

data_member_count =The number of data members when creating a RAID 5 or RAID 6 devices on a Symmetrix array with Enginuity version 5772 and higher.

Set the value to 3 or 7 for RAID 5 (3+1) and RAID 5 (7+1) or, 6 or 14 for RAID 6 (6+2) and RAID 6 (14+2).

 

 

3.

Build a command file

Enter the following command notation (create dev) in a command file. This can be done with a text editor, such as Notepad or the vi UNIX editor. For this example, the file is called addbcvs.cmd.

 

For example, to add a Symmetrix BCV device as a 2-way mirror to Symmetrix array 000000012345 with a size of 1100 cylinders (516 MB), using FBA emulation, create a command file containing the following command line:

 

create dev count=1, size=1100,emulation=FBA, config=2-Way-BCV-Mir;

 

Or, you could build a RAID BCV. To add a Symmetrix BCV device as a RAID-6 BCV to Symmetrix array 000000012345 with a size of 1100 cylinders (516 MB), using FBA emulation, create a command file containing the following command line:

 

create dev count=1, size=1100,emulation=FBA, config=BCV-R-6;

 

 

4.

Commit the file to create the device

Then commit the file to activate the device creation command:

 

symconfigure -sid 12345 -file addbcvs.cmd -v -noprompt commit

 

 

 

7Table of Contents

 

 

·        Establishing BCV Pairs 

 

Overview

Uses for BCV copies (TimeFinder mirroring) can include backup, restore, decision support, and application testing. After configuration and initialization of a Symmetrix array, BCV devices contain no data. The full establish operation must be used the first time the standard devices are paired with their BCV devices.  (For an incremental establish operation, see step note 5.)

 

This procedure is based on content from the following EMC manual:

·         EMC Solutions Enabler Symmetrix TimeFinder Family Product Guide

 

You can download the guide from EMC Online Support (registration required): https://support.EMC.com

 

 

1.   

Associate the BCV for pairing

To perform TimeFinder mirroring or standard/BCV pairing, the standard and BCV mirror devices of your production images must be members of the same device group.  Initially, for the creation of given standard/BCV pair, the potential BCV device must first be associated with an existing device or device group. When you associate a BCV device with a standard device, you can assign it a logical device name. If not, a logical device name gets assigned automatically. You can explicitly associate one BCV to a standard device or a range of BCVs to the working TimeFinder device group.

 

To associate BCV001 with device 001F, enter:


  symbcv –g DgName [–sid SymmID] associate dev 001F BCV001

 

Or to associate a range of devices to a device group, enter:

 

symbcv –g DgName [–sid SymmID] associateall dev –RANGE 087:08A

 

 

2.   

Full Establish the pair

To obtain a copy of the data on a standard device, the BCV device of the pair must be established.

 

To initiate a full establish on a specific standard/BCV device pair, target the standard device and enter:


  symmir –g DgName –full establish DEV001

 

3.   

Full Establish all pairs in a group

To initiate a full establish on all BCV pairs in a device group, enter:

  symmir –g DgName –full establish

 

4.   

Verify the establish operation completes (Synchronized)

To verify when the BCV pairs reach the full copied or Synchronized state, use the verify action as follows:

 

 symmir –g DgName –i 30 verify

 

With this interval and count, the message is displayed every 30 seconds until the pair is established.

 

5.   

Note: Incremental Establish and other options

After any standard/BCV pair has been fully established and subsequently split, to save establish (resync) time, you can perform an establish operation omitting the -full option, which updates the BCV copy with only the changed tracks that occurred on the standard device during the elapsed BCV split time. To perform an incremental establish, omit the –full option, targeting the standard device of the pair:

   symmir -g DgName establish DEV001

 

Optionally, you can also collectively target all devices in a device group, composite group, or defined devices in a device file:

  symmir –g DgName establish [-full]

  symmir –g CgName establish [-full]

    symmir –sid SymmID –file FileName establish [-full]

 

For more information about operations with TimeFinder/Mirror pairs, see the Solutions Enabler Symmetrix TimeFinder Family CLI Product Guide.

 

 

 

7Table of Contents

 

 

·        Working with Unprotected BCV Devices

 

Overview

For higher, safe, data availability, it is recommended that every BCV in your Symmetrix device configuration list be created with mirrored protection. This procedure deals with correcting a BCV device discovered in your storage array that was mistakenly configured as a single mirrored device.

 

This procedure is based on content from the following EMC manual:

  • EMC Solutions Enabler Symmetrix Array Controls CLI Product Guide

 

You can download the guide from EMC Online Support (registration required): https://support.EMC.com

 

 

1.

Look for unprotected BCVs

Examine your Symmetrix configuration for unprotected BCVs by examining the output from a Symmetrix device list. To see all the various devices mapped to your host, enter the following command:

 

symdev –sid SymmID list –cyl -bcv

 

In the output, look for any BCV notation in the list under the Config heading. If the notation BCV exists for any Symmetrix device in the list, this is an unprotected device and it must be changed to a mirrored BCV type for data protection.

 

In this example, Symmetrix device 009C was found with a device type of BCV. Perform the remaining steps to make this device into a mirrored BCV.

 

2.

About the convert device command

To convert a Symmetrix BCV device, use the following syntax in the command file:

 

convert dev SymDevName[:SymDevName] to DeviceConfig

  [emulation=EmulationType,]

 

where:

 

SymDevName The Symmetrix device name of the device targeted for change. You can also target a range of contiguous device names.

 

Emulation = The device emulation type, which currently must be fixed block architecture (FBA), CELERRA FBA, VME512 FBA, or CKD-3380 or CKD-3390 for z/OS environments.

 

DeviceConfigFor mirrored protection, the desired device configuration type for this case must be: 2-Way-BCV-Mir

 

 

3.

Build a command file

Enter the following command notation (convert dev) in a command file. This can be done with a text editor, such as Notepad or the vi UNIX editor. For this example the file is called convertbcv.cmd.

 

To convert a single-mirror Symmetrix BCV device (009C) in Symmetrix array 000000012345 as a two-way mirrored BCV, using FBA emulation, enter the following command line in a file:

 

convert dev 009C to 2-Way-BCV-Mir emulation=FBA;

 

 

4.

Split the BCV pair

Split the standard/BCV pair targeting the standard device.

 

symmir –g TFgroup split

 

 

5.

Cancel the BCV pair

Cancel the standard/BCV device pair relationship.

 

symmir –g TFgroup cancel DEV001 BCV dev 009C

 

 

6.

Commit the file to convert the device

Then commit the file to activate the device conversion command:

 

symconfigure -sid 12345 -file convertbcv.cmd -v -noprompt commit

 

 

 

7.

Resync the BCV pair and check

Perform a full-establish on the BCV pair.

 

symmir –g TFgroup establish -full DEV001 BCV dev 009C

 

To confirm the configuration change on the device is in effect, perform a symdev list command to see the changed configuration of the device.

 

 

7Table of Contents