tape29_BESTn /dev/rtape/tape29_BESTnb
<— Tape device special files
Finding the lockdown path
Procedure
1.
The load-balance policy used to route data on multiple paths to a tape drive or library is called the
"path-lockdown" policy. Use the
scsimgr get_info
command to see the current lockdown path for
a library.
For example:
># scsimgr get_info -D /dev/rchgr/autoch35
STATUS INFORMATION FOR LUN : /dev/rchgr/autoch38 ... LUN Path used when policy is
path_lockdown = 0/0/0/9/0/0/1.0x50014382c6e4f009.0x1000000000000
2.
Use the
scsimgr get_attr
command to see the current lockdown path for a library.
For example:
# scsimgr get_attr -D /dev/rtape/tape28_BEST
SCSI ATTRIBUTES FOR LUN : /dev/rtape/tape28_BEST ... name = lpt_lockdown
current = 0/0/0/9/0/0/0.0x100000e00222a6c1.0x2000000000000 default = saved =
3.
For additional information, see the HP-UX man pages:
scsimgr (1M) , ioscan (1M) , mknod (2) , mksf (1M) , rmsf (1M)
Troubleshooting advanced path failover
Cause
Advanced path failover errors are logged in the
/var/adm/syslog/syslog.log
file as part of the
default SCSI I/O tracing function of HP-UX. You can use standard file viewing commands, including
cat
,
vi
,
dmesg -
, and
tail -f
, to view the
syslog.log
file.
Enabling or disabling advanced path failover
Advanced path failover is disabled by default. When advanced path failover is disabled, the driver
operates as if the device is not capable of using the advanced path failover feature.
When advanced failover is enabled for the library or tape drive, the device resets itself and must be
opened using the device special file before the driver will recognize it as an advanced path failover device
and use the failover features of the driver. Opening the device is generally done by the host applications.
You can enable or disable advanced path failover using the library web-based interface. For instructions,
see:
Procedure
1. Configuring failover for the ESL G3 Tape Libraries
on page 21
2. Enabling data path failover
on page 35
When advanced path failover is disabled, the passive control paths to the library will go into an error state
(NO_HW) in the ioscan (1M) command output. These stale entries do not affect the function of the library.
To clear these errors so the device can be accessed using its device special file:
62
Finding the lockdown path
