However, the user can choose to enable access to that stale copy, which instructs the system to return the state of that volume to the point in time of that stale copy. Because this change is a step-by-step change to the volume state, be careful with this process. Do not perform this process if any data or state from the volume is cached in host systems. Ideally, shut down the host systems that use the volume before you perform these steps. By running these commands without these precautions, you will almost certainly crash your applications and might corrupt the stale copy. We show an example where a problem occurred with the Primary copy during a resynchronization between sites as shown in Example 6-19. Example 6-19 lsrcrelationship example IBM_Storwize:ITSO_V7K_HyperSwap:superuser>lsrcrelationship 0 id 0 name rcrel0 master_cluster_id 0000020076805032 master_cluster_name dizzy master_vdisk_id 0 master_vdisk_name vdisk0 aux_cluster_id 0000020076805032 aux_cluster_name dizzy Note: Example 6-18 shows 2 Quorum Disk and the IP Quorum as active Quorum. This reflect our lab. configuration. If you have implemented the Quorm Disk you will see it instead of the IP Quorum.
172 IBM Storwize V7000, Spectrum Virtualize, HyperSwap, and VMware Implementation aux_vdisk_id 6 aux_vdisk_name vdisk6 primary master consistency_group_id 0 consistency_group_name rccstgrp0 state consistent_copying bg_copy_priority 50 progress 81 freeze_time 2015/08/11/12/16/47 status online sync out_of_sync copy_type active_active cycle_period_seconds 300 cycling_mode master_change_vdisk_id 1 master_change_vdisk_name vdisk1 aux_change_vdisk_id 7 aux_change_vdisk_name vdisk7 As shown in Example 6-19 on page 171, the HyperSwap Volumes are still resynchronizing. The consistent_copying state of the volume shows a resynchronization where the Secondary copy contains a stale image, and the value that is contained in the freeze_time field shows when that image dates from. The progress value increases toward 100 as the resynchronization process continues. See the progress 83 line in Example 6-20. Now, the site of the Primary copy goes offline as shown in Example 6-20. Example 6-20 lsrcrelationship out_of_sync example IBM_Storwize:ITSO_V7K_HyperSwap:superuser>lsrcrelationship 0 . many lines omitted for brevity . state consistent_copying bg_copy_priority 50 progress 83 freeze_time 2015/03/04/12/16/47 status primary_offline sync out_of_sync many lines omitted for brevity IBM_Storwize:ITSO_V7K_HyperSwap:superuser>lsvdisk id name IO_group_id IO_group_name status mdisk_grp_id mdisk_grp_name capacity type FC_id FC_name RC_id RC_name vdisk_UID fc_map_count copy_count fast_write_state se_copy_count RC_change compressed_copy_count 0 vdisk0 0 io_grp0 offline 0 mdiskgrp0 250.00MB striped many many 0 rcrel0 6005076801DA0140C800000000000000 2 1 empty 0 no 0 With the only up-to-date copy of the volume offline, the active-active relationship cannot switch direction to keep the HyperSwap Volume online, so the Master Volume is now offline as shown in Example 6-20.
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