Unisphere for VMAX: Operation on device fails with "Cannot use the device for this function because it is a Copy Session target"

           

   Article Number:     503294                                   Article Version: 12     Article Type:    Break Fix 
   

 


Product:

 

Unisphere for VMAX,Solutions Enabler,VMAX3 Series,PowerMaxOS 5978,TimeFinder,Symmetrix Remote Data Facility (SRDF),TimeFinder SnapVX

 

Issue:

 

 

Using Unisphere for VMAX/PowerMax to complete a SYMAPI operation on a device (for example expand a VMAX3 thin device),   
    or using a SYMCLI command (for example symdev modify -tdev -cap) fails with message:   

      Cannot use the device for this function because it is a Copy Session target   
   
    The following message may be encountered for devices involved in a Replication session:   
      Cannot expand volumes that are being replicated or are currently part of a replication session.   
   
    For failed expand device example, Unisphere for VMAX/PowerMax smas.log contains:   

      09:16:18,007 WARN  [em.bp.UTIL] (default task-63) SymapiCallTracer:InputArgs::SymThinDeviceExpand failed with code 3587 (Cannot use the device for this function because it is a Copy Session target)       
        Handle = 2       
        Symid = 0000000000xxx       
        Gflags = SYMAPI_EXPAND_DEV_GFLGS_NONE       
        class emc.widesky.symapi.datastructs.SYMAPI_EXPAND_DEV_RANGE_REQ_T@397745fb {       
         Format = SYMAPI_CFGCHG_DEF_FMT_1       
         Exp_flags = SYMAPI_EXPAND_DEV_RANGE_NOFLAGS       
         Start_dev = 000       
         End_dev = 000       
         New_dev_size = 559241       
         Dev_size_unit = SYMAPI_DEV_UNITS_CYLS       
         P_next = null       
        } Expand_req
   

   

      09:16:18,009 ERROR [em.smc.STORAGE] (default task-63) VolumeTaskExecutor.executeFastCreateVolumeThinTask:Cannot use the device for this function because it is a Copy Session target     
      Note: The Start_dev and End_dev are given in Decimal, so convert to hexadecimal to get the VMAX array device number   

   

      From the symapi.log:   

   

      09:16:18.005   8959     31 EMC:UNIVMAX               emcFastCanDevRangeBe Device 00000 is a Snap Target device   

   

      For symrdf control operations that return "Cannot use the device for this function because it is a Copy Session target", the symapi.log can contains:   

   

      EMC:SYMRDF                SymDgRdfControl()    grp: <group>  ldev:  actionP: <Action> - Cannot use the device for this function because it is a Copy Session target (local sid/dskno <Array Serial Number>/<Symdev>) (remote sid/dskno <Array Serial Number>/<Symdev>)       
        EMC:SYMRDF                emcRdfUtilEvalRdfCon SYMAPI_C_DEVICE_IS_SNAP_TGT - R1 device <Symdev> (SID: <Array Serial Number>) is a SNAP/CLONE TGT device
   

   

     
      Commands like symclone list, symsnap list and symsnapvx list, symsnapvx list -linked do not list the device as being in a TimeFinder Clone, Snap  or SnapVX copy session.   

                                                             

 

 

Cause:

 

 

For TDEV devices running with HYPERMAX OS (5977), expand function is not allowed when the TDEV is already involved in a Replication session (SRDF), TimeFinder Copy Session (SnapVX, XCOPY).    
   
    For TDEV devices running with PowerMax OS (5978), expand function is not allowed when the TDEV is already involved in a SRDF/Metro session.   
   
    An FBA device that is involved in VAAI activity (VMware Storage API for Array Integration) initiated from VMware ESXi hosts (e.g. Storage vMotion, VM clone) utilizes Extent-level TimeFinder copy session.   
   
    EMC Solutions Enabler does not initiate or report on VAAI operations, nor does Unisphere for VMAX/PowerMax monitor such activity.   
   
    The only place that Solutions Enabler reports on a device involved in a an XCOPY operation is in the field "Extent Based Clone" when executing the following SYMCLI:   
   
    symdev -sid <sid> show <dev>   
        

      Extent Based Clone       : None     
          
    When it is involved in a XCOPY (or Extent SNAP or SYNC XCOPY) session it will show:   
      Extent Based Clone       : Source   
    or   
      Extent Based Clone       : Target   
   
     
      Note 1: Unisphere for VMAX/PowerMax device details does not show the "Extend based Clone" property.        
       
        Note 2: Solutions Enabler returns Source or Target in
symdev show property "Extent Based Clone" for devices involved in Extent-level TimeFinder copy session for XCOPY on FBA devices or Extent SNAP on CKD (Mainframe) devices     
          
                                                             

 

 

Resolution:

 

 

In general, the involved Replication (SRDF) or Copy (TimeTinder or Extent-level TimeFinder)  session needs to be ended.   
    For SRDF devices, this means using symrdf deletepair command.   
    Note: For SRDF devices in SRDF/Metro session, additional considerations need to be taken into account for an TDEV expand procedure, please contact Dell EMC Support or your Account Team quoting this article to get guidance on the expand procedure that is particular to your environment and operational constraints.    
   
    For Extent level session, meaning symdev show shows  Extent Based Clone       : None before the SYMAPI operation can be completed successfully on the device.   
   
    For example, VAAI activities are short by nature, so typically it is enough to re-issue the SYMAPI operation after a short amount of time.   
    If the VMware environment is very active, and the SYMAPI operation continues to fail because the symdev show command continues to report an Extent Based Clone, XCOPY can be disabled on the ESXi host(s) until the expansion is complete.   
    Instructions on how to dynamically disable XCOPY can be found in this whitepaper:     

    Dell EMC Support only recommends disabling XCOPY as a last resort, and once the SYMAPI operation has completed, XCOPY should be re-enabled on the impacted ESXi host(s).   
   
    Note: With Solutions Enabler 9.0 (and above), TDEV (FBA) on PowerMaxOS arrays (5978 and above) can be expanded (symdev modify -tdev -cap) when the device is in a replication/copy session (SnapVX, SRDF, XCOPY).   
      From Solutions Enabler V9.0, expansion of thin devices in the following replication relationships is supported on arrays running PowerMaxOS 5978:     
      SnapVX Source and fully defined Linked Target devices     
      SnapVX Source with fully defined restore session     
      SRDF R1 and R2 devices     
      Cascaded RDF devices     
      Concurrent RDF devices     
      Devices with SDDF session     
      Devices with Clone Extent, CCOPY and XRS sessions     
      Devices with user defined geometry or GCM   
    The exception is a TDEV in a SRDF/Metro session, expand is not allowed.