Srdfsynchronous operations 7 copyright 2015 emc

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SRDF/Synchronous Operations
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7 Copyright 2015 EMC Corporation. All rights reserved. The symrdf addgrp command creates an empty Dynamic SRDF group on the source and the target VMAX arrays and logically links them. The directors and the respective ports have to be specified in the command for VMAX3 arrays. Note: The physical links and communication between the two arrays must exist for this command to succeed. Note: The SRDF group number in the command ( -rdfg and remote_rdfg ) is in decimal. In the Symmetrix, it is converted to hexadecimal. The decimal group numbers start at 01 but the hexadecimal group numbers start at 00. Hence the hexadecimal group numbers will be off by one. We have created an RDF Group with the label SRDF_Sync and the RDF Group number 10 in decimal. Shown in parenthesis is the hexadecimal value 9. It would be convenient if the SRDF group numbers on the local and the remote arrays were identical, however, this is not a requirement. SRDF/Synchronous Operations
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8 Copyright 2015 EMC Corporation. All rights reserved. The symrdf createpair command takes the dynamic capable device pairs listed in the text file (pairs.txt) and makes them R1-R2 pairs. On VMAX3 arrays, devices are created as Dynamic capable by default. By specifying establish the newly created R2 devices are synchronized with the data from the newly created R1 devices. In this example the file contains the following entries: pairs.txt 059 087 05A 088 The first column in the file lists the devices on the VMAX3 on which the command is executed (in our example SID:483 ) and the second column is the remote VMAX3 (in our example SID:225 ). Specifying type R1 makes the device in the first column to be R1s and the devices in the second column will become their corresponding R2s. The mode of operation for the SRDF pairs that are newly created is set to Adaptive Copy Disk Mode (discussed later in this module) by default. SRDF/Synchronous Operations
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9 Copyright 2015 EMC Corporation. All rights reserved. As noted earlier, the SRDF mode is by default set to Adaptive Copy Disk. The establish operation synchronizes data from the new R1 device to the new R2 device. The R1 devices are created on SID:483 and their corresponding R2 devices are created on SID:225 . R1 device 059 is paired with R2 device 087 . R1 device 05A is paired with R2 device 088 . Legend for MODE: M (ode of Operation) : A = Async, S = Sync, E = Semi-sync, C = Adaptive Copy : M = Mixed A (daptive Copy) : D = Disk Mode , W = WP Mode, . = ACp off C(onsistency State) : X = Enabled, . = Disabled, M = Mixed, - = N/A (Consistency) E(xempt): X = Enabled, . = Disabled, M = Mixed, - = N/A SRDF/Synchronous Operations
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10 Copyright 2015 EMC Corporation. All rights reserved. The delete SRDF pairs command cancels SRDF pairs in the device file specified. Before the deletepair can be invoked, the pair must be suspended first. The RDF Group is not deleted by this operation. If the RDF Group should be deleted, then the symrdf removegrp command should be used after the deletepair operation.
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