HP 3PAR InForm OS 3.1.1 CLI Administrator's Manual

Active and Inactive Hosts
An active host is a host that is connected to a system port and recognized by the InForm OS. Under
normal operation, an active host may have a number of volumes exported to it and therefore the
host has access to those volumes.
An inactive host is a host that is known to the InForm OS but is not recognized as being connected
to any system port at the moment. This may be because the host is currently disconnected from the
system port, or due to an error condition such as link failure or because the host is offline.
When a host on a system port becomes inactive for any reason, the following happens:
1. The InForm OS recognizes that the host is missing on the port and changes the state of the
host from active to inactive.
2. The InForm OS remembers all volumes exported to the host before it became inactive. It
will not unexport the volumes on the port with the missing host.
3. If and when the host reappears on the same port, the InForm OS will change the state of the
host to active again. At that time, the host will have access to all previously exported volumes
as before.
Managing Hosts
The system sees a host as a set of initiator port WWNs (World Wide Names) or iSCSI Names.
The InForm OS administration tools allow you to create, modify, and remove Fibre Channel and
iSCSI host paths and their properties. When creating a new host, you can either create a host with
or without assigning WWNs or iSCSI Names. A virtual volume that is exported to a host is exported
to all the WWNs that make up the host. If you need to export virtual volumes to particular host
computer WWNs or iSCSI Names, you can create separate hosts on the system and assign each
WWN or iSCSI Name to its own host. The host management commands are described in detail
in the HP 3PAR InForm OS Command Line Interface Reference and the CLI Help Pages.
Host Management CLI Commands
Use the following CLI commands to manage hosts and host paths:
• showhost - display information about defined hosts and host paths in the system.
• createhost - create a host or add paths to host.
• createhostset - create a host set or add a host to an existing host set.
• sethost - modify properties of existing hosts.
• sethostset - change the name of a host set.
• removehost - remove a system host or paths to a host.
• removehostset - remove a host set from the system, or remove hosts from a set.
• servicehost - executes removal and replacement actions for a host.
Creating Hosts
When you create a new host, you are actually defining the characteristics of a new host path from
the system to the host. Defining host characteristics includes the assignment of a name to a host,
and the assignment of a path to that host. Two types of host paths can be assigned: FC or iSCSI
paths. You should create multiple paths to each host.
In addition to assigning FC or iSCSI paths when creating a host, you can also annotate the host
with descriptive information such as the host’s location, IP address, operating system, model, and
owner using either the createhost or sethost commands. This information is for annotation
purposes only and it does not affect the operation of the system. See the HP 3PAR InForm OS
Command Line Interface Reference or InForm OS CLI Help for further information. To create a host
70 Managing Ports and Hosts