76
IBM System Storage N series Hardware Guide
iSCSI network-attached topologies
are topologies in which the hosts are attached to
storage controllers through Ethernet switches. Networks can contain multiple Ethernet
switches in any configuration.
Mirrored HA pair configuration
is similar to the standard HA pair configuration, except
that there are two copies, or
plexes
, of the data. This configuration is also called
data
mirroring
.
Remote storage
refers to the storage that is accessible to the local node, but is at the
location of the remote node.
Single storage controller configurations
are topologies in which there is only one storage
controller is used. Single storage controller configurations have a single point of failure and
do not support cfmodes in Fibre Channel SAN configurations.
Standard HA pair configuration
refers to a configuration set up in which one node
automatically takes over for its partner when the partner node becomes impaired.
7.2 HA pair types and requirements
The following types of HA pairs are available, each having distinct advantages and
requirements:
Standard HA pairs
Mirrored HA pairs
Stretch MetroClusters
Fabric-attached MetroClusters
Each of these HA pair types is described in the following sections.
7.2.1 Standard HA pairs
In a standard HA pair, Data ONTAP functions so that each node monitors the functioning of its
partner through a heartbeat signal that is sent between the nodes. Data from the NVRAM of
one node is mirrored by its partner. Each node can take over the partner’s disks or array
LUNs if the partner fails. Also, the nodes synchronize time.
Standard HA pairs have the following characteristics:
Standard HA pairs provide high availability by pairing two controllers so that one can serve
data for the other in case of controller failure or other unexpected events.
Data ONTAP functions so that each node monitors the functioning of its partner through a
heartbeat signal that is sent between the nodes.
Data from the NVRAM of one node is mirrored by its partner. Each node can take over the
partner’s disks or array LUNs if the partner fails.
Tip: You must follow certain requirements and restrictions when you are setting up a new
HA pair configuration. These restrictions are described in the following sections.
Summary of Contents for N Series
Page 2: ......
Page 12: ...x IBM System Storage N series Hardware Guide ...
Page 18: ...xvi IBM System Storage N series Hardware Guide ...
Page 20: ...xviii IBM System Storage N series Hardware Guide ...
Page 22: ...2 IBM System Storage N series Hardware Guide ...
Page 32: ...12 IBM System Storage N series Hardware Guide ...
Page 52: ...32 IBM System Storage N series Hardware Guide ...
Page 64: ...44 IBM System Storage N series Hardware Guide ...
Page 90: ...70 IBM System Storage N series Hardware Guide ...
Page 122: ...102 IBM System Storage N series Hardware Guide ...
Page 194: ...174 IBM System Storage N series Hardware Guide ...
Page 200: ...180 IBM System Storage N series Hardware Guide ...
Page 224: ...204 IBM System Storage N series Hardware Guide ...
Page 244: ...224 IBM System Storage N series Hardware Guide ...
Page 292: ...272 IBM System Storage N series Hardware Guide ...
Page 298: ...278 IBM System Storage N series Hardware Guide ...
Page 300: ...280 IBM System Storage N series Hardware Guide ...
Page 314: ...294 IBM System Storage N series Hardware Guide ...
Page 326: ...306 IBM System Storage N series Hardware Guide ...
Page 327: ... Copyright IBM Corp 2012 2014 All rights reserved 307 Part 5 Appendixes Part 5 ...
Page 328: ...308 IBM System Storage N series Hardware Guide ...
Page 362: ...342 IBM System Storage N series Hardware Guide ...
Page 366: ...IBM System Storage N series Hardware Guide IBM System Storage N series Hardware Guide ...
Page 367: ......