Solutions Enabler: Symclone establish fails when SRDF/A is running

Summary: Could not perform the symclone incremental establish when R2 devices as source are in a consistent state.

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Symptoms

When SRDF devices are set to Async mode, R2 devices would be in a consistent state, so symclone establish would be failed as shown below: 
  
symrdf -g test_dg que 
  
Device Group (DG) Name       : test_dg
DG's Type                    : ANY
DG's Symmetrix ID            : 000xxxxxxxxx    (Microcode Version: 5876)
Remote Symmetrix ID          : 000yyyyyyyyy    (Microcode Version: 5876)
RDF (RA) Group Number        :  57 (38)         
Target (R2) View                         Source (R1) View     FLAGS
---------------------------------    ------------------------ ----- ------------
               ST                 LI       ST
Standard        A                  N        A
Logical  Sym    T R1 Inv  R2 Inv   K Sym    T R1 Inv  R2 Inv        RDF Pair
Device   Dev    E Tracks  Tracks   S Dev    E Tracks  Tracks  MCES  STATE
--------------------------------- -- ------------------------ ----- ------------
SRC01693  01693 WD      0       0 RW 04C32 RW       0       0 AX.E  Consistent
SRC03AA3 03AA3 WD       0       0 RW 02FCB RW       0       0 AX.E  Consistent 
Total             ------- -------             ------- -------
  Track(s)              0       0                   0       0
  MB(s)               0.0     0.0                 0.0     0.0 
Legend for FLAGS: 
(M)ode of Operation : A = Async, S = Sync, E = Semi-sync, D = Adaptive Copy Disk Mode
                    : W = Adaptive Copy WP Mode, M = Mixed, T = Active
(C)onsistency State : X = Enabled, . = Disabled, M = Mixed, - = N/A
(E)xempt            : X = Enabled, . = Disabled, M = Mixed, - = N/A
R1/R2 Device (S)ize : E = R1 EQ R2, 1 = R1 GT R2, 2 = R2 GT R1, - = N/A
symclone -g test_dg   establish -consistent -tgt 
  
Execute 'Incremental Establish' operation for device group
'test_dg' (y/[n]) ? y 
'Incremental Establish' operation execution is in progress for
device group 'test_dg'. Please wait... 

The request is not allowed for SRDF/A-capable devices in async mode

Cause

When an R2 device in asynchronous mode is being used as a clone source, symclone establish command fails 
because an "establish" performs "recreate/activate" moments apart from each other. The precopy would never get a chance to be effective.

However -precopy or -copy can be used to maintain the SRDF/A consistency session while creating a clone copy.

Resolution

To create a consistent clone copy, perform the "recreate/activate" commands separately a bit apart, instead of single establish command that includes both actions in tandem. 

Example below: 
  
symclone -g "test_dg" recreate -precopy -tgt
symclone -g "test_dg" activate -tgt -consistent

That would effectively work in place of the symclone establish.

Affected Products

PowerMax, Solutions Enabler Series, VMAX, VMAX All Flash, VMAX3 Series
Article Properties
Article Number: 000208281
Article Type: Solution
Last Modified: 08 Feb 2023
Version:  1
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