This is due sysfs being pseudo filesystem, as procfs is as well.
It's actually an interface from kernel space to user space which allows you to manipulate various options regarding your hardware or operating system values.
Options such as fibre rescan, ip4 forwarding etc are all controlled by user using those pseudo file systems.
A lot of those options have real backed configuration files (such as /etc/sysctl.conf) which will apply those on boot.
That file system is created after system is booted (or on request) and populated with your device files.
For instance, if you add additional fibre card, a sysfs will be populated with additional hierarchy for that card.
An actual echo command is predetermined, if you issue anything else error will be written.
Take the following example from my PC at home :
Hope that helps
Regards
Peasant.
These 2 Users Gave Thanks to Peasant For This Post:
Hi,
I was trying to customize this archaic HP-UX box. only shell available is ksh and that too seems to be pretty old and doesn't completely conform to what I read on the web about ksh. Anyway here are my issues:
- I wanted to have a dynamic title on xterm or dtterm. I put the following lines... (2 Replies)
Hi all,
Encountered a wierd behaviour which I am unable to understand.
I have a function doing the follow:
function RETRIEVE_PASSWORD
{
if (( $DC_ACCOUNT ))
then
clear
printf "\nEnter Password for ${ConfiguredUser}"
printf... (1 Reply)
Hi,
I am cutting data from a fixed length test file and then writing out a new record using the echo command, the problem I have is how to stop multiple spaces from being written to the output file as a single space.
Example:
cat filea | while read line
do
field1=`echo $line | cut -c1-2`
... (6 Replies)
Please forgive me if I've chosen the wrong forum... but I'm just wondering how likely it is to find a Linux sys admin with a vast BEA Weblogic skillset or vice versa (a Weblogic admin with vast Linux admin skills)?
The reason I ask is because our Linux Sys Admin is leaving for a position with... (1 Reply)
Hello,
well what I'm trying to do is to remove underscores from filenames and leaving empty spaces instead:
arturas@Universe:/windows/Center/training$ ls
big_file failas su shudu
arturas@Universe:/windows/Center/training$ a=big_file
arturas@Universe:/windows/Center/training$ mv $a `echo... (8 Replies)
Hey im new in this...anything will be helpful...
The user will input the word or phrase .... I want to search the user input in file (by lines) but not all then with this line search on another file ( with the specific line) and show to the user.
Example:
file1.txt
=======
a
aa
aaa... (2 Replies)
Is there any way in a script to print out the commands being ran? In DOS script, there is the "@echo on" and "@echo off".
so I have a script like this:
#!/bin/ksh
echo "hello there. moving files."
<turn on echoing here>
cp thisfile.txt thatfile.txt
cp whatfile.prop whyfile.prop
<turn... (2 Replies)
Hi,
I keep getting this error when i run my script:
No matter how many times i run this rm -rf /siebel/sfs/tmp/dump it succeeds when i expect it only the first time to succeed becoz i expect the second to fail as the directory should be gone in the first run.
i had earlier mentioned... (5 Replies)
Discussion started by: mohtashims
5 Replies
LEARN ABOUT LINUX
hpsa
HPSA(4) Linux Programmer's Manual HPSA(4)NAME
hpsa - HP Smart Array SCSI driver
SYNOPSIS
modprobe hpsa [ hpsa_allow_any=1 ]
DESCRIPTION
hpsa is a SCSI driver for HP Smart Array RAID controllers.
Options
hpsa_allow_any=1: This option allows the driver to attempt to operate on any HP Smart Array hardware RAID controller, even if it is not
explicitly known to the driver. This allows newer hardware to work with older drivers. Typically this is used to allow installation of
operating systems from media that predates the RAID controller, though it may also be used to enable hpsa to drive older controllers that
would normally be handled by the cciss(4) driver. These older boards have not been tested and are not supported with hpsa, and cciss(4)
should still be used for these.
Supported hardware
The hpsa driver supports the following Smart Array boards:
Smart Array P700M
Smart Array P212
Smart Array P410
Smart Array P410i
Smart Array P411
Smart Array P812
Smart Array P712m
Smart Array P711m
StorageWorks P1210m
Configuration details
To configure HP Smart Array controllers, use the HP Array Configuration Utility (either hpacuxe(8) or hpacucli(8)) or the Offline ROM-based
Configuration Utility (ORCA) run from the Smart Array's option ROM at boot time.
FILES
Device nodes
Logical drives are accessed via the SCSI disk driver (sd(4)), tape drives via the SCSI tape driver (st(4)), and the RAID controller via the
SCSI generic driver (sg(4)), with device nodes named /dev/sd*, /dev/st*, and /dev/sg*, respectively.
HPSA-specific host attribute files in /sys
/sys/class/scsi_host/host*/rescan
This is a write-only attribute. Writing to this attribute will cause the driver to scan for new, changed, or removed devices (e.g,.
hot-plugged tape drives, or newly configured or deleted logical drives, etc.) and notify the SCSI midlayer of any changes detected.
Normally a rescan is triggered automatically by HP's Array Configuration Utility (either the GUI or the command-line variety); thus,
for logical drive changes, the user should not normally have to use this attribute. This attribute may be useful when hot plugging
devices like tape drives, or entire storage boxes containing preconfigured logical drives.
/sys/class/scsi_host/host*/firmware_revision
This attribute contains the firmware version of the Smart Array.
For example:
# cd /sys/class/scsi_host/host4
# cat firmware_revision
7.14
HPSA-specific disk attribute files in /sys
/sys/class/scsi_disk/c:b:t:l/device/unique_id
This attribute contains a 32 hex-digit unique ID for each logical drive.
For example:
# cd /sys/class/scsi_disk/4:0:0:0/device
# cat unique_id
600508B1001044395355323037570F77
/sys/class/scsi_disk/c:b:t:l/device/raid_level
This attribute contains the RAID level of each logical drive.
For example:
# cd /sys/class/scsi_disk/4:0:0:0/device
# cat raid_level
RAID 0
/sys/class/scsi_disk/c:b:t:l/device/lunid
This attribute contains the 16 hex-digit (8 byte) LUN ID by which a logical drive or physical device can be addressed. c:b:t:l are
the controller, bus, target, and lun of the device.
For example:
# cd /sys/class/scsi_disk/4:0:0:0/device
# cat lunid
0x0000004000000000
Supported ioctl() operations
For compatibility with applications written for the cciss(4) driver, many, but not all of the ioctls supported by the cciss(4) driver are
also supported by the hpsa driver. The data structures used by these ioctls are described in the Linux kernel source file
include/linux/cciss_ioctl.h.
CCISS_DEREGDISK, CCISS_REGNEWDISK, CCISS_REGNEWD
These three ioctls all do exactly the same thing, which is to cause the driver to rescan for new devices. This does exactly the
same thing as writing to the hpsa-specific host "rescan" attribute.
CCISS_GETPCIINFO
Returns PCI domain, bus, device and function and "board ID" (PCI subsystem ID).
CCISS_GETDRIVVER
Returns driver version in three bytes encoded as:
(major_version << 16) | (minor_version << 8) |
(subminor_version)
CCISS_PASSTHRU, CCISS_BIG_PASSTHRU
Allows "BMIC" and "CISS" commands to be passed through to the Smart Array. These are used extensively by the HP Array Configuration
Utility, SNMP storage agents, and so on. See cciss_vol_status at <http://cciss.sf.net> for some examples.
SEE ALSO cciss(4), sd(4), st(4), cciss_vol_status(8), hpacucli(8), hpacuxe(8),
<http://cciss.sf.net>, and Documentation/scsi/hpsa.txt and Documentation/ABI/testing/sysfs-bus-pci-devices-cciss in the Linux kernel source
tree
Linux 2012-08-05 HPSA(4)