NAME

ap_dmd - AP disk meta-driver

SYNOPSIS

ap_dmd@target,lun:partition

DESCRIPTION

The ap_dmd driver works with the AP software to support Alternate Pathing for physical devices handled by the ssd SCSI disk driver. See ssd(7) in man Pages(7): Device and Network Interfaces of the SunOS Reference Manual.

The AP feature lets you configure alternate SCSI paths to a physical device. These paths are associated with a meta-disk device, which is one of the file system special nodes associated with a particular meta-driver.

ap_dmd allows the AP Librarian, ap(7), to configure or unconfigure physical paths to a SCSI device via an interface that allows APSET, APUNSET, and APSWITCH commands. These commands are issued by ap(7) at the behest of the user-invoked AP commands and AP daemon. To change the SCSI path information associated with a particular ap_dmd device, use apconfig(1M), apdb(1M) and apdisk(1M). For more information, see the Sun Enterprise Server Alternate Pathing User's Guide.

All device operations supported by the ssd driver are also valid on ap_dmd devices that have been created via AP commands. See the other AP commands for details regarding other components of AP software, and ssd(7) man page for information about block/character file accesses, I/O requests, disk partitioning schemes, CD-ROM support, and ioctls.

ERRORS

ENXIO

No physical SCSI path to the target device exists.

Other

For information on other errors, see sd(7).

FILES

apdmd.conf

driver configuration file

/dev/ap/dsk/mncntndnsn

block files

/dev/ap/rdsk/mncntndnsn

raw files

where m identifies the device as a meta-device and:

cn

Controller number

tn

Target number

dn

Logical unit number

sn

Slice (partition) number

DIAGNOSTICS

See ssd(7) in man Pages(7): Device and Network Interfaces of the SunOS Reference Manual.

ap_dmd ( 7 ) SEE ALSO

Sun Enterprise Server Alternate Pathing User's Guide

apconfig(1M), apdb(1M), apdisk(1M), apnet(1M), ap_daemon(1M), ap(7), ap_nmd(7) in this reference manual

ssd(7) in man Pages(7): Device and Network Interfaces of the SunOS Reference Manual