Dell EqualLogic PS6210XS EqualLogic Group Manager Administrator s Guide PS Ser - Page 309

Figure 32. Synchronous Replication 1. The iSCSI initiator sends a write to the group. 2. Data is simultaneously written to both the SyncActive and SyncAlternate volumes. 3. The SyncActive and SyncAlternate volumes confirm to the group that the writes are complete. 4. The write is confirmed to the iSCSI initiator. SyncAlternate Volume Unavailable If the group can write to the SyncActive volume, but can no longer write to the SyncAlternate volume, initiator access to the volume continues without disruption, as shown in Figure 33. SyncAlternate Volume Unavailable. Figure 33. SyncAlternate Volume Unavailable 1. The SyncAlternate volume becomes unavailable. 2. Initiator access to the volume continues without interruption. The volume is out of sync. 3. The group tracks all changes written to the volume. 4. When the SyncAlternate volume becomes available, tracked changes are written to the SyncAlternate volume, as shown in Figure 34. Tracked Changes Written to SyncAlternate Volume. About Synchronous Replication 309