IBM N series Hardware Manual page 95

Table 7-1 Configuration types
HA pair If A-SIS
configuration active
type
Standard HA pair No
configuration
Mirrored HA pair Yes
configuration
Stretch Yes
MetroCluster
Fabric-attached Yes
MetroCluster
a. SAS configurations are limited to 5 meters between nodes
Certain terms have the following particular meanings when they are used to refer to HA pair
configuration:
HA pair configuration
An
each other if one of the two systems becomes impaired. In Data ONTAP documentation
and other information resources, HA pair configurations are sometimes also called
pairs
When a system is in an HA pair configuration, systems are often called
sometimes called the
node
Controller failover
that enables two storage systems to take over each other's data. This configuration
improves data availability.
FC direct-attached topologies
the storage system. Direct-attached systems do not use a fabric or Fibre Channel
switches.
FC dual fabric topologies
independent fabrics that are connected to storage systems. Each independent fabric can
consist of multiple Fibre Channel switches. A fabric that is zoned into two logically
independent fabrics is not a dual fabric connection.
FC single fabric topologies
systems through a single Fibre Channel fabric. The fabric can consist of multiple Fibre
Channel switches.
iSCSI direct-attached topologies
the storage controller. Direct-attached systems do not use networks or Ethernet switches.
Distance between
nodes
a
Up to 500 meters
a
Up to 500 meters
Up to 500 meters
(270 meters if Fibre
Channel speed 4 Gbps
and 150 meters if Fibre
Channel speed is 8
Gbps)
Up to 100 km depending
on switch configuration.
For gateway systems, up
to 30 km.
is a pair of storage systems that are configured to serve data for
.
local node
.
, which is also called
are topologies in which each host is attached to two physically
are topologies in which the hosts are attached to the storage
Failover possible
after loss of entire
node (including
storage)
No
No
Yes
Yes
, and the other node is called the
cluster failover
are topologies in which the hosts are directly attached to
are topologies in which the hosts are directly attached to
Chapter 7. Highly Available controller pairs
Notes
Use this configuration to provide
higher availability by protecting
against many hardware single
points of failure.
Use this configuration to add
increased data protection to the
benefits of a standard HA pair
configuration.
Use this configuration to provide
data and hardware duplication
to protect against a local
disaster.
Use this configuration to provide
data and hardware duplication
to protect against a larger-scale
disaster.
nodes
. One node is
partner node
or
(CFO), refers to the technology
HA
remote
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