Dell PowerVault MD3820f - Manual (Page 76)

To start or stop the Host Context Agent on Windows:
1. Do one of the following:
– Click Start → Settings → Control Panel → Administrative Tools → Services
– Click Start → Administrative Tools → Services
2. From the list of services, select Modular Disk Storage Manager Agent.
3. If the Host Context Agent is running, click Action → Stop, then wait approximately 5 seconds.
4. Click Action → Start.
I/O Data Path Protection
You can have multiple host-to-array connections for a host. Ensure that you select all the connections to
the array when configuring host access to the storage array.
NOTE: See the Deployment Guide for more information on cabling configurations.
NOTE: For more information on configuring hosts, see About Your Host .
If a component such as a RAID controller module or a cable fails, or an error occurs on the data path to
the preferred RAID controller module, virtual disk ownership is moved to the alternate non preferred RAID
controller module for processing. This failure or error is called failover.
Drivers for multi-path frameworks such as Microsoft Multi-Path IO (MPIO) and Linux Device Mapper (DM)
are installed on host systems that access the storage array and provide I/O path failover.
For more information on Linux DM, see
Device Mapper Multipath for Linux . For more information on
MPIO, see microsoft.com.
NOTE: You must have the multi-path driver installed on the hosts at all times, even in a
configuration where there is only one path to the storage system, such as a single port cluster
configuration.
During a failover, the virtual disk transfer is logged as a critical event, and an alert notification is sent
automatically if you have configured alert destinations for the storage array.
Managing Host Port Identifiers
You can do the following to manage the host port identifiers that are added to the storage array:
• Add — Add or associate a new host port identifier to a particular host.
• Edit — Change the host port identifier alias or user label. You can move (associate) the host port
identifier to a new host.
• Replace — Replace a particular host port identifier with another host port identifier.
• Remove — Remove the association between a particular host port identifier and the associated host.
To manage a host port identifier:
1. In the AMW, select the Host Mappings tab.
2. Perform one of these actions:
– Right-click the host in the object tree, and select Manage Host Port Identifiers in the pop-up
menu.
– From the menu bar, select Host Mappings → Manage Host Port Identifiers.
The Manage Host Port Identifiers dialog is displayed.
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