HP UNIX Listing all hardware devices.
Listing all hardware:
Using ioscan:
Disclaimer: Apply to a TEST environment first. Use on production systems is at DBAs own risk.
Device addresses with ioscan.
Important options:
-f: full listing
–F: compact listing
-C: lists only the specified class
-n: lists device name
-u: : using cached info from when the system was booted.
ioscan –f
à -f: full listing.
ioscan –f | lp
à To print, if you have a networked printer.
ioscan –funC disk
à To see disks only.
ioscan –funC tape
à To see tapes only.
ioscan –FnC disk
à -n : physically goes and interrogates the current status and history of all disks.
Listing Device files:
Disks, block device:
Block device file: buffering a block of data into memory and then it is sent/written to the block device disk, (default 8000 characters are buffered, then are sent to the block device).
ll /dev/dsk displays a listing as below:
brw-|r–|— 1 bin sys 31 0×005000 c0t5d0
b: is for block device.
1: it’s got one hard link.
31: is the major number: it points to a section of code in Kernel that tells the software how to talk to this disk.
0×005000: is the minor number: is the device number which is the same as the device number from ioscan –f.
lssf /dev/rdsk/c0t5d0
à Use lssf to get identification for a disk.
Disks, raw or character device:
Character device file: Accepting one character at a time. We are communicating with the device one character at the time.
ll /dev/rdsk displays a listing as below:
crw-|r–|— 1 bin sys 188 0×005000 c0t5d0
c: is for character device.
If some of the block device files or character device files are accidentally removed, then if you reboot the system, HP Unix will re-install them automatically or you could manually re-install them:
insf -eC disk :to re-install just disks.
insf -e :to re-install all devices.
rmsf :to remove any unneeded device files.
When you need to remove a given device, you will need to use rmsf to remove the device file associated with it.
Tapes:
ll /dev/rmt
àDisplays device file name as below:
c1tod0 BEST :best density possible.
BESTb :best density possible and use Berkeley style semantic.
BESTn :best density possible but do not rewind.
BESTnb :best density possible and rewind.
DDS :lowest density possible.
0m is hard linked to BEST, 0mn is linked to BESTn.
lssf /dev/rmt/om
àTo get identification for a tape.
Using ioscan to identify tapes:
ioscan –funC tape :listing system tapes.
Device file naming convention:
c0t5d0 d0: is the device number. In case you have multiple disks on a single target address such as a RAID disk; or a piece of hardware with multiple disks.
t5: is the scsi target address.
c0: is the instance number. When system is rebooted an instance# is assigned to the device in order of their response, first respond would get the 0, then 1, etc.
Physical disks:
To determine how many physical disks (not partitions) you have on your system do:
ll /dev/dsk
or ll /dev/rdsk
/dev/dsk and /dev/rdsk points to the same physical disks, but write to them either character by character (/dev/rdsk) or 8k blocks at a time (/dev/dsk).
The number of disks you see within /dev/dsk is the number of physical disks you have on your system.
Size of a disk:
diskinfo /dev/rdsk/c0t5d0
Note that his only works with raw device files (rdsk).
Listing current file systems:
bdf
à This lists all currently mounted file systems and how they are mapped into volume groups and logical groups.
For example the following is a single line extracted from bdf command:
/dev/vg00/lvol6 1105920 569478 505227 53% /var
à This line is basically saying that file system /var is mapped to logical volume lvol6 which is a part of volume group vg00. /var is sized 1GB (1105920K), 556MB (569478K) of which is being used and it has 493MB (505227K) of free space; meaning 53% used.