Installation guide

-U Command
Gets the UID command. T he UID command is a command the gnbd_export command will run
to get a Universal Identifier for the exported device. T he UID is necessary to use device-mapper
multipath with GNBD. The command must use the full path of any executeable that you wish to
run. A command can contain the %M, %m or %n escape sequences. %M will be expanded to
the major number of the exported device, %m will be expanded to the minor number of the
exported device, and %n will be expanded to the sysfs name for the device. If no command is
given, GNBD will use the default command /usr/sbin/gnbd_get_uid. T his command will
work for most SCSI devices.
Examples
This example is for a GNBD server configured with GNBD multipath. It exports device /dev/sdc2 as
GNBD gam m a. Cache is disabled by default.
gnbd_expo rt -d /dev/sdc2 -e gamma -U
This example is for a GNBD server not configured with GNBD multipath. It exports device /dev/sdb2 as
GNBD delta with cache enabled.
gnbd_expo rt -d /dev/sdb1 -e delta -c
This example exports device /dev/sdb2 as GNBD delta with cache enabled.
gnbd_expo rt -d /dev/sdb2 -e delta -c
3.2. Importing a GNBD on a Client
The gnbd.ko kernel module must be loaded on a node before it can import GNBDs. When GNBDs are
imported, device nodes are created for them in /dev/gnbd/ with the name assigned when they were
exported.
Usage
gnbd_import -i Server
Server
Specifies a GNBD server by hostname or IP address from which to import GNBDs. All GNBDs
exported from the server are imported on the client running this command.
Example
This example imports all GNBDs from the server named nodeA.
gnbd_import -i nodeA
Red Hat Enterprise Linux 5 Global Network Block Device
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