Figure 1-4
Service switchover through remote replication
Standby host
Secondary storage system
Production host
Remote replication
links interrupted
Primary storage system
Secondary storage system
Standby host
The standby
host takes over
services.
Remote replication
links
Production host
Primary storage system
Secondary storage system
Standby host
The production
host runs services.
Primary site
Secondary site
Links interrupted
Production host
Primary storage system
3. The secondary site takes over services.
·
Administrator sets the access permission of
secondary LUNs manually to accessible.
·
The secondary site takes over services from
the primary site to ensure service continuity.
·
The remote replication links are interrupted.
·
The pair between the primary and
secondary LUNs is broken.
2. The primary site encounters a disaster.
·
The primary LUN is accessible to hosts but
the secondary LUN is not.
·
The primary site copies data to the secondary
site.
1. The primary site is working properly.
Phases in a service switchover
Primary
LUN
Secondary
LUN
Primary
LUN
Secondary
LUN
Secondary
LUN
Primary
LUN
Read only
Read
/Write
Read only
NOTE
After a primary/secondary switchover, the respective primary and secondary sites record changed data to
avoid full synchronization when the secondary site becomes the primary site.
1.3.4 Data Recovery
If a failure occurs at the primary site of a remote replication task, the secondary site
temporarily takes over its services. When the primary site recovers, it regains control of those
services.
When the primary site recovers from a disaster, it is required to rebuild a remote replication
between primary and secondary storage systems. And you can use the data on the secondary
site to recover the primary site.
shows how the storage system recovers data at the
primary site after a disaster.
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.
15