Cisco Cisco MDS 9000 SANTap Guía De Información
Solution Overview
Cisco DMM software runs on a Cisco MDS 9000 Series Switch module. The module can be inserted into a free slot
while the switch operates, without rewiring or reconfiguring existing SANs. If the switch already contains the
appropriate module, the migration process is started simply by activating a software license. Neither the source nor
the target array needs to be directly connected to the module, and no downtime is required for the host server before
or during the migration, until the final cutover. In fact, the server will be unaware that data is being copied to a new
location. This technology frees storage, network, system, and application administrators from the need to coordinate
host downtime and eliminates much of the user impact commonly associated with data migrations.
while the switch operates, without rewiring or reconfiguring existing SANs. If the switch already contains the
appropriate module, the migration process is started simply by activating a software license. Neither the source nor
the target array needs to be directly connected to the module, and no downtime is required for the host server before
or during the migration, until the final cutover. In fact, the server will be unaware that data is being copied to a new
location. This technology frees storage, network, system, and application administrators from the need to coordinate
host downtime and eliminates much of the user impact commonly associated with data migrations.
Activating a Cisco DMM license initiates an enterprise-class solution capable of moving up to 1.5 terabytes (TB) of
data per hour between any storage devices across a heterogeneous network. Administrators can select synchronous
migration to move data to a new array within the data center, or asynchronous migration to move data to a SAN in a
remote data center.
data per hour between any storage devices across a heterogeneous network. Administrators can select synchronous
migration to move data to a new array within the data center, or asynchronous migration to move data to a SAN in a
remote data center.
Synchronous migration supports a dual fabric topology, with one Cisco DMM node in each fabric. The Cisco DMM
engine redirects traffic from each host and mirrors write operations to the existing and new storage devices
(Figure 1). Meanwhile, a background process copies the data from the existing storage device to the new device, so
the migration occurs in real time.
engine redirects traffic from each host and mirrors write operations to the existing and new storage devices
(Figure 1). Meanwhile, a background process copies the data from the existing storage device to the new device, so
the migration occurs in real time.
Figure 1.
Figure 1 Synchronous Data Migration
Asynchronous migration is better suited to migrating data between data centers. In this case Cisco DMM again uses
a dual fabric topology and redirects traffic through the Cisco DMM engine, but it does not mirror the I/O to the new
storage device. Instead, it keeps a log of all the data blocks that are changed. Then the logs are synchronized using
the IP interface of the network, and data is moved in the background.
a dual fabric topology and redirects traffic through the Cisco DMM engine, but it does not mirror the I/O to the new
storage device. Instead, it keeps a log of all the data blocks that are changed. Then the logs are synchronized using
the IP interface of the network, and data is moved in the background.
Cisco DMM is supported on the Cisco MDS 9000 18/4-Port Multiservice Module (MSM) and the Cisco MDS 9222i
Multiservice Modular Switch. Both require Cisco MDS 9000 NX-OS Software Version 4.1 or later.
Multiservice Modular Switch. Both require Cisco MDS 9000 NX-OS Software Version 4.1 or later.
Business Benefits
The nondisruptive, fabric-based approach of Cisco DMM makes the process of data migration faster, easier, and less
expensive.
expensive.
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