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6 TR1081 | Microsoft SQL Server Database Protection Using EqualLogic Auto-Snapshot Manager / Microsoft Edition
2.3 Overview of HIT Groups
A HIT Group is a group of one or more hosts that are managed from ASM/ME. HIT Groups are useful
because they allow multi-host management from any machine that is running ASM/ME. For example, if an
administrator has to manage and backup Microsoft SQL Server databases residing on multiple instances
and servers, they can create a HIT Group on a single instance of ASM/ME and manage multiple servers
from there.
2.3.1 HIT Groups in Non-Cluster Environments
In non-cluster environments, HIT Groups are host-specific. That is, adding host B to the ASM/ME instance
on host A does not automatically add host A to the ASM/ME instance on host B. A HIT Group can also
consist of one host. Adding multiple hosts to manage is optional; ASM/ME can also be run from a single
host and managed on that local host.
2.3.2 HIT Groups in Cluster Environments
In cluster environments, all cluster nodes in a HIT Group have a reciprocal relationship. That is, adding
cluster node B to the ASM/ME instance on cluster node A will automatically add cluster node A to the
ASM/ME instance on cluster node B. All cluster nodes must be added to the HIT Group for proper
operation. ASM/ME will then automatically set up the trust relationship between each cluster node. If only
a subset of cluster nodes is added to a HIT Group, then data restoration, schedules, and Smart Copy
operations could result in fatal errors. When ASM/ME is installed and run from one cluster node, ASM/ME
will send a warning if the other nodes have not been included in the HIT Group.
2.4 Multi-Host Management
The design of ASM/ME includes multi-host management or centralized management through a single
ASM/ME instance.
In the past, ASM/ME was managed on each application server and operations were single hosted. Starting
with ASM/ME version 4.0, multiple hosts can be managed through the same ASM/ME interface and
operations such as setting alerts, backup document locations, notifications, and setting CHAP credentials,
can all be applied to each managed host concurrently. In addition hosts can be added to an ASM/ME
instance simply by using the Add Hosts feature.
The Add Hosts feature will allow administrators to add new hosts to the ASM/ME instance. Hosts can be
looked up in 3 ways, Figure 3, such as discovering through the PS Series Group, browsing the network via
AD lookup, and/or manually entering the host information.
Note: The Computer Browser service must be enabled and started on the ASM/ME host and domain
controllers in order to browse the network.