How to create swap file in RedhatLinux Server

hello, guys today i will tell you how can we create the swap file in a Linux .swap is part of virtual part of heard disk.  basically, swap part is a system  used like RAM .so if we create swap file  or partition .if  we can increase our system swap memory step

step 1- before we create any file and then we convert in swap memory kile this 
#touch a.txt                                      (a.txt is filename )

#dd if=/dev/zero of=a.txt bs=1M count=1000

here we format swap file

#mkswap a.txt

here we will below commands through on swap

#swapon a.txt

we will check below commands

#free -m

then we will permanent swap file

# vim /etc/fstab    (note -here we will go to insert mod through (i) commands and we will save ( press Ese then press :wq)

/root/file swaps                                           swpas                         default                        0 0

:wq   (then save to swap file )

Thank you

by vishnu sharma

 

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how to configure raid 5 in redhat linux server

Hii guys today we will discuss about RAId5 .RAID 5 is a method of storage management in linux server. In this article  we will learn how to configure RAID 5 in linux server  if u want to know what is RAID? and what is RAID 0 RAID1 so click on my link and visit What is raid 0 ? and how to Configur in redhat linux server What is raid 0 ? and how to Configur in redhat linux server

basically RADID 5 in required 3 heard disk if one is crashes then other disk will be take place automaticly .

So lets go through the steps to configure raid level 5 in linux server

[root@localhost ~]# fdisk /dev/sda
The number of cylinders for this disk is set to 4177.
There is nothing wrong with that, but this is larger than 1024,
and could in certain setups cause problems with:
1) software that runs at boot time (e.g., old versions of LILO)
2) booting and partitioning software from other OSs
   (e.g., DOS FDISK, OS/2 FDISK)
Command (m for help): m
Command action
   a   toggle a bootable flag
   b   edit bsd disklabel
   c   toggle the dos compatibility flag
   d   delete a partition
   l   list known partition types
   m   print this menu
   n   add a new partition
   o   create a new empty DOS partition table
   p   print the partition table
   q   quit without saving changes
   s   create a new empty Sun disklabel
   t   change a partition's system id
   u   change display/entry units
   v   verify the partition table
   w   write table to disk and exit
   x   extra functionality (experts only)
Command (m for help): p
Disk /dev/sda: 34.3 GB, 34359738368 bytes
255 heads, 63 sectors/track, 4177 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
   Device Boot      Start         End      Blocks   Id  System
/dev/sda1   *           1        3315    26627706   83  Linux
/dev/sda2            3316        3697     3068415   82  Linux swap / Solaris
/dev/sda4            3698        4177     3855600    5  Extended
/dev/sda5            3698        3722      200781   fd  Linux raid autodetect
/dev/sda6            3723        3747      200781   fd  Linux raid autodetect
Command (m for help): n
Command action
   l   logical (5 or over)
   p   primary partition (1-4)
l
First cylinder (3748-4177, default 3748):
Using default value 3748
Last cylinder or +size or +sizeM or +sizeK (3748-4177, default 4177): +100M
Command (m for help): n
Command action
   l   logical (5 or over)
   p   primary partition (1-4)
l
First cylinder (3748-4177, default 3748):
Using default value 3748
Last cylinder or +size or +sizeM or +sizeK (3748-4177, default 4177): +100M
Command (m for help): n
Command action
   l   logical (5 or over)
   p   primary partition (1-4)
l
First cylinder (3761-4177, default 3761):
Using default value 3761
Last cylinder or +size or +sizeM or +sizeK (3761-4177, default 4177): +100M
Command (m for help): n
Command action
   l   logical (5 or over)
   p   primary partition (1-4)
l
First cylinder (3774-4177, default 3774):
Using default value 3774
Last cylinder or +size or +sizeM or +sizeK (3774-4177, default 4177): +100M
Command (m for help): p
Disk /dev/sda: 34.3 GB, 34359738368 bytes
255 heads, 63 sectors/track, 4177 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
   Device Boot      Start         End      Blocks   Id  System
/dev/sda1   *           1        3315    26627706   83  Linux
/dev/sda2            3316        3697     3068415   82  Linux swap / Solaris
/dev/sda4            3698        4177     3855600    5  Extended
/dev/sda5            3698        3722      200781   fd  Linux raid autodetect
/dev/sda6            3723        3747      200781   fd  Linux raid autodetect
/dev/sda7            3748        3760      104391   83  Linux
/dev/sda8            3761        3773      104391   83  Linux
/dev/sda9            3774        3786      104391   83  Linux
Command (m for help): t
Partition number (1-9): 7
Hex code (type L to list codes): l
 0  Empty           1e  Hidden W95 FAT1 80  Old Minix       bf  Solaris
 1  FAT12           24  NEC DOS         81  Minix / old Lin c1  DRDOS/sec (FAT-
 2  XENIX root      39  Plan 9          82  Linux swap / So c4  DRDOS/sec (FAT-
 3  XENIX usr       3c  PartitionMagic  83  Linux           c6  DRDOS/sec (FAT-
 4  FAT16 <32M      40  Venix 80286     84  OS/2 hidden C:  c7  Syrinx
 5  Extended        41  PPC PReP Boot   85  Linux extended  da  Non-FS data
 6  FAT16           42  SFS             86  NTFS volume set db  CP/M / CTOS / .
 7  HPFS/NTFS       4d  QNX4.x          87  NTFS volume set de  Dell Utility
 8  AIX             4e  QNX4.x 2nd part 88  Linux plaintext df  BootIt
 9  AIX bootable    4f  QNX4.x 3rd part 8e  Linux LVM       e1  DOS access
 a  OS/2 Boot Manag 50  OnTrack DM      93  Amoeba          e3  DOS R/O
 b  W95 FAT32       51  OnTrack DM6 Aux 94  Amoeba BBT      e4  SpeedStor
 c  W95 FAT32 (LBA) 52  CP/M            9f  BSD/OS          eb  BeOS fs
 e  W95 FAT16 (LBA) 53  OnTrack DM6 Aux a0  IBM Thinkpad hi ee  EFI GPT
 f  W95 Ext'd (LBA) 54  OnTrackDM6      a5  FreeBSD         ef  EFI (FAT-12/16/
10  OPUS            55  EZ-Drive        a6  OpenBSD         f0  Linux/PA-RISC b
11  Hidden FAT12    56  Golden Bow      a7  NeXTSTEP        f1  SpeedStor
12  Compaq diagnost 5c  Priam Edisk     a8  Darwin UFS      f4  SpeedStor
14  Hidden FAT16 <3 61  SpeedStor       a9  NetBSD          f2  DOS secondary
16  Hidden FAT16    63  GNU HURD or Sys ab  Darwin boot     fb  VMware VMFS
17  Hidden HPFS/NTF 64  Novell Netware  b7  BSDI fs         fc  VMware VMKCORE
18  AST SmartSleep  65  Novell Netware  b8  BSDI swap       fd  Linux raid auto
1b  Hidden W95 FAT3 70  DiskSecure Mult bb  Boot Wizard hid fe  LANstep
1c  Hidden W95 FAT3 75  PC/IX           be  Solaris boot    ff  BBT
Hex code (type L to list codes): fd
Changed system type of partition 7 to fd (Linux raid autodetect)
Command (m for help): t
Partition number (1-9): 8
Hex code (type L to list codes): fd
Changed system type of partition 8 to fd (Linux raid autodetect)
Command (m for help): t
Partition number (1-9): 9
Hex code (type L to list codes): fd
Changed system type of partition 9 to fd (Linux raid autodetect)
Command (m for help): p
Disk /dev/sda: 34.3 GB, 34359738368 bytes
255 heads, 63 sectors/track, 4177 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
   Device Boot      Start         End      Blocks   Id  System
/dev/sda1   *           1        3315    26627706   83  Linux
/dev/sda2            3316        3697     3068415   82  Linux swap / Solaris
/dev/sda4            3698        4177     3855600    5  Extended
/dev/sda5            3698        3722      200781   fd  Linux raid autodetect
/dev/sda6            3723        3747      200781   fd  Linux raid autodetect
/dev/sda7            3748        3760      104391   fd  Linux raid autodetect
/dev/sda8            3761        3773      104391   fd  Linux raid autodetect
/dev/sda9            3774        3786      104391   fd  Linux raid autodetect
Command (m for help): w
The partition table has been altered!
Calling ioctl() to re-read partition table.
WARNING: Re-reading the partition table failed with error 16: Device or resource busy.
The kernel still uses the old table.
The new table will be used at the next reboot.
Syncing disks.
[root@localhost ~]# partprobe /dev/sda
[root@localhost ~]# mdadm --create /dev/md5 --level=5 --raid-devices=3 /dev/sda7 /dev/sda8 /dev/sda9
mdadm: array /dev/md5 started.

then we will create raid5 like this
[root@localhost ~]# mdadm –create /dev/md5 –level=5 –raid-devices=3 /dev/sda7 /dev/sda8 /dev/sda9
mdadm: array /dev/md5 started

you can also check raid5

[root@localhost ~]# cat /proc/mdstat
Personalities : [raid6] [raid5] [raid4]
md5 : active raid5 sda9[2] sda8[1] sda7[0]
      208640 blocks level 5, 64k chunk, algorithm 2 [3/3] [UUU]

 

thank you

by vishnu sharma

What is raid 0 ? and how to Configure in redhat linux server

Hii guys today i will show you how to Configure raid 0 in redhat linux server. But before i telling you what is raid 0 ? .actually raid 0 is  part of  storage management methord in server .it s provide fast speed in data storage.Raid 0  is also called a stripe set   In other words raid 0 does not provide data redundancy. Is just provide fast speed and high performance. Here i make raid 0 in linux partition.we can also used in real machine

How to create partition in linux redhat

hello guys today we will learn how to create partition in readhat linux server .we can also implement in real heard drive .

what is loop devise ? and how to create loop in redhat linux

hello guys today we will learn how to create loop before we know what is loop .loop device is  connected to an existing file in the filesystem.

at fast we create blank 200mb file
# dd if=/dev/zero of=file bs=m1 count=200 (create for blank file )
# losetup /dev/loop0 file (configure loop0)
# losetup -a (looking for loop0)
# mkdir data (create data folder )
# mkfs.ext3 /dev/loop0 (format loop0)
# mount /dev/loop0 data (loop is mount in data folder)
# df -h (looking for mount loop0)

we can remove to following cmd..
at fast we remove permanently go to vim /etc/fstab and umount
# umount data ( loopo unmount to data folder )
# losetup -d /dev/loop0 (delet loop0)
# losetup -a
# rm -rf file (delet foe file)