my confusion is still same . looks to me as i am unable to undersatnd it
please answer my query . also before putting my question in forum i have already gone throgh this wiki page
let consider jgt's example
as per him
it means that drive 4 will contain the data of drive 1 drive 2 and drive 3
and if any drive get failed it will serch data in drive 4
is this is what you want to say am i right
or
each 4 drive have a same data and ata time only one drive is active and rest is passive mode. if suppose drive one got failed in that case drive 2 become active and so on
also please explain below line. i know i am asking stupid type question and reflecting my poor IQ too this time
here pls explain what is striping and block level striping in raid. with example
what is distributed parity in raid with example pls
About associative nature of awk arrays i'm still confused, not able to understand yet how array element can be accessed based on a string, I got one example at gawk manual to illustrate associative nature of awk arrays, it goes here:
Codeawk '
# Print list of word frequencies
{
for (i = 1;... (3 Replies)
i am not able to understand the following code for awk:
$awk -F"|" '{ kount++}
>END { for (desig in kount)
> print desig,kount }' emp.list
the input file i.e. emp.list is ::
3432| p.k.agrwal |g.m |sales
4566|g.l.sharma |director|production
3433|r shah | g.m | production... (1 Reply)
Hi
I am unable to understand the disk layout of one of my disk attached to v240. This is newly installed system from jumpstart.
I am unable to see the free space on backup slice 2 and there are 0 to 8 slices listed when I run format and print the disk info, also there is no reference of... (9 Replies)
Hello,
I have a RHEL system with two 500GB hard drives in RAID 1 (I think hardware, but not 100% certain - any way to tell?).
It looks like it was just set up in default configuration with a small boot partition and one huge partition for the rest, which composes a LVM volume.
I want... (1 Reply)
I m executing ps command and sorting it according to memory usage.
Please find the output of the command.
# ps aux --sort pmem
USER PID %CPU %MEM VSZ RSS TTY STAT START TIME COMMAND
root 1 0.0 0.0 2060 624 ? Ss 01:54 0:00 init
root 2 0.0... (1 Reply)
Hello,
I have a scsi pci x raid controller card on which I had created a disk array of 3 disks
when I type lspv ; I used to see 3 physical disks ( two local disks and one raid 5 disk )
suddenly the raid 5 disk array disappeared ; so the hardware engineer thought the problem was with SCSI... (0 Replies)
I found out that the raid 1 was degraded:
# cat /proc/mdstat
Personalities :
md3 : active raid1 sda5 sdb5
1822445428 blocks super 1.0
md2 : active raid1 sda3(F) sdb3
1073741688 blocks super 1.0
md1 : active raid1 sda2 sdb2
524276 blocks super 1.0
md0 : active raid1 sda1... (0 Replies)
Hi geeks,
I am trying to understand below if statement. can someone please explain me meaning of if condition.
if ]
then
echo -e "1"
fi
Thanks
Please use CODE tags. (3 Replies)
Hi
below is the samll awk script which i am not able to understand properly.
here a bit confusion in 2nd line for me
1. why *\ is not used before . in second line as it was used in first line *\$*\. */
2. why always \ is used in every first line
3. is there any specific meaning... (9 Replies)
Hi,
I am trying to set ulimit for soft stack unlimited, but this is not taking effect, after tracing the ulimit -a unlimited command, the below output was generated, which i am unable to comprehend. Could any one help me with this?
prcbap1-r10prod: truss -d ulimit -s unlimited
Tue Dec 30... (2 Replies)
Discussion started by: NasirAbbasi
2 Replies
LEARN ABOUT REDHAT
sd
SD(4) Linux Programmer's Manual SD(4)NAME
sd - Driver for SCSI Disk Drives
SYNOPSIS
#include <linux/hdreg.h> /* for HDIO_GETGEO */ #include <linux/fs.h> /* for BLKGETSIZE and BLKRRPART */
CONFIG
The block device name has the following form: sdlp, where l is a letter denoting the physical drive, and p is a number denoting the parti-
tion on that physical drive. Often, the partition number, p, will be left off when the device corresponds to the whole drive.
SCSI disks have a major device number of 8, and a minor device number of the form (16 * drive_number) + partition_number, where drive_num-
ber is the number of the physical drive in order of detection, and partition_number is as follows:
partition 0 is the whole drive
partitions 1-4 are the DOS "primary" partitions
partitions 5-8 are the DOS "extended" (or "logical") partitions
For example, /dev/sda will have major 8, minor 0, and will refer to all of the first SCSI drive in the system; and /dev/sdb3 will have
major 8, minor 19, and will refer to the third DOS "primary" partition on the second SCSI drive in the system.
At this time, only block devices are provided. Raw devices have not yet been implemented.
DESCRIPTION
The following ioctls are provided:
HDIO_GETGEO
Returns the BIOS disk parameters in the following structure:
struct hd_geometry {
unsigned char heads;
unsigned char sectors;
unsigned short cylinders;
unsigned long start;
};
A pointer to this structure is passed as the ioctl(2) parameter.
The information returned in the parameter is the disk geometry of the drive as understood by DOS! This geometry is not the physical
geometry of the drive. It is used when constructing the drive's partition table, however, and is needed for convenient operation of
fdisk(1), efdisk(1), and lilo(1). If the geometry information is not available, zero will be returned for all of the parameters.
BLKGETSIZE
Returns the device size in sectors. The ioctl(2) parameter should be a pointer to a long.
BLKRRPART
Forces a re-read of the SCSI disk partition tables. No parameter is needed.
The scsi(4) ioctls are also supported. If the ioctl(2) parameter is required, and it is NULL, then ioctl() will return -EINVAL.
FILES
/dev/sd[a-h]: the whole device
/dev/sd[a-h][0-8]: individual block partitions
SEE ALSO scsi(4)
1992-12-17 SD(4)