3.7.0 HP StorageWorks HP Scalable NAS File Serving Software command reference guide HP Scalable NAS for Linux (AG513-96003, October 2009)

Description
NOTE:
HP recommends that Device Mapper Multipath, the Linux-based MPIO solution, be
used in HP Scalable NAS clusters. However, HP Scalable NAS supports other MPIO
solutions, including the mxmpio command described here. See the HP Scalable
NAS File Serving Software administration guide for more information.
HP Scalable NAS uses multipath I/O (MPIO) to eliminate single points of failure. A
cluster can include multiple Fibre Channel switches, multiple FC ports per server, and
multiported SAN disks. This configuration provides multiple paths for I/O between
servers and SAN disks.
When you start HP Scalable NAS, it automatically configures all paths from each
server to the storage devices. On each server, it uses the first path it discovered for
I/O with the SAN devices. If that path fails, HP Scalable NAS automatically fails
over the I/O to another path.
The mxmpio command can be used to display status information about MPIO devices
or to control the path used for I/O. With the exception of enableall and
disableall, all commands take PSD device names to operate on specific devices.
If you do not specify a PSD device, the command operates on all devices.
The options are:
-l
Long option. Provides more detail about targets. This option does not apply to
enableall or disableall.
-u
Display I/O latencies in microseconds instead of the default milliseconds. This
option applies only to the iostat command.
The commands are:
{enable/disable} [<psddev> ...]
Enable or disable MPIO failover on the specified devices.
{enableall/disableall}
Globally enable or disable MPIO failover on this node.
timeout <value> [<psddev> ...]
Set the timeout on the specified device.
active <target> [<psddev> ...]
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