Huawei OceanStor 2200 V3 - Page 20

Figure 1-3 Writing process in asynchronous remote replication mode
1
Host
Primary
LUN
DCL
Secondary
LUN
1
7
1
5
6
4
3
Snapshot
Snapshot
2
2
Secondary
Cache
Snapshot
Snapshot
5
7
4
Primary
storage system
Secondary
storage system
Remote replication links
Pri
mar
y
Primary
Primary
LUN
Primary
LUN
差异位图
Secondary
LUN
Secondary
LUN
snapshot
The primary LUN
snapshot is created
The secondary LUN
snapshot is stopped.
The primary LUN
snapshot is stopped.
1
7
5
3
6
4
2
7
Primary
LUN
Primary
LUN
snapshot
Secondary
LUN
Secondary
LUN
snapshot
DCL
Data block N
Records the difference in the DCL
Write I/O
result
Eliminates the
difference
in the DCL.
Incremental data is synchronized
to the secondary cache
Primary
Cache
Secondary
Cache
Data block N
The secondary LUN
snapshot is created
4
1
Data block N
2
Write I/O
result
Data block N
5
Data is replicated from the primary cache and LUN to the secondary cache.
Primary
Cache
RM
RM
RM: Remote replication management module.
DCL: Data change log.
OceanStor V3 Series
Remote Replication Feature Guide for Block
1 Feature Description
Issue 06 (2018-01-30) Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
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