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Archive for the ‘Operating Systems’ Category

Volume Group Status Area (VGSA)

Friday, February 13th, 2015

Information about which PPs that are stale and which PVs are missing within a VG. The LVM and SCSI driver reserves somewhere between 7-10% of the available disk space for LVM maps, etc.

Ref:

http://www.datadisk.co.uk/html_docs/hp/aix_lvm.htm

Volume Group Descriptor Area (VGDA)

Friday, February 13th, 2015

Information about all the LVs and PVs within a VG. The first 64K of a PV is reserved for this area – defined in <sys/bootrecord.h>.

The VGDA consists of

  • BOOTRECORD: – first 512 bytes. Allows the Read Only System (ROS) to boot system
  • BAD BLK DIRECTORY – found in <sys/bddir.h>
  • LVM RECORD – found in <lvmrec.h>

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Volume Group Characteristics

Friday, February 13th, 2015

You can find below the meaning of each parameter on Volume Group Characteristics (the output from lsvg vg command):

 

  1. Volume Group: Name of Volume Group.
  2. VG State: active/partial. Partial indicates that some of the Physical Volumes in the Volume Group are not active.
  3. VG Permission: It indicates if the volume group is read-only or read-write.
  4. Max LVs: Maximum number of Logical Volumes allowed in Volume Group.
  5. LVs: Total number of Logical Volumes at present in Volume Group.
  6. Open LVs: Number of LVs open at present in the Volume Group for any Read Write operation.
  7. Total PVs: Total number of Physical Volumes present in Volume Group.
  8. Stale PVs: How many stale Physical Volumes are there in Volume Group. The stale Physical Volumes are those ones on which I/O operations are not possible.
  9. Active PVs: Total number of Physical Volumes which are active in Volume Group.
  10. Max PPs per VG: Maximum no. of Physical Partitions which can be there in the Volume Group.
  11. Max PPs per PV: Maximum number of Physical Partitions which can be there in Physical Volume.
  12. VG Identifier: The very long string to identify Volume Group.
  13. PP Size: The size of Physical Partition used in every Physical Volume of Volume Group.
  14. Total PPs: Total number of Physical Partitions in Volume Group.
  15. Free PPs: Total number of free Physical Partitions with in Volume Group.
  16. Used PPs: Total number of Physical Partitions in use in Volume Group.
  17. Quorum: Whether the quorum is on or not in Volume Group.
  18. VG Descriptors: Number of Volume Group Descriptor Areas(VGDA) in Volume Group.
  19. Stale PPs: How many Physical Partitions are stale or unable to perform I/O operations.
  20. Auto On: Whether the Volume Group will varyon on system startup or not.
  21. Max PVs: Maximum number of Physical Volumes allowed in this Volume Group.
  22. Auto Sync: Whether this Volume Group should sync automatically or not.
  23. BB Policy: Its bad block relocation policy. So, this value here is relocatable, that means we are allowed to relocate bad blocks in this Volume Group if need be.

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en vs et vs ent

Monday, February 9th, 2015

most of us has  confused between the network devices en, et & ent, you can read the following to put a limit for this confusion 🙂 :

ent:
The notation ent is used to specify the hardware adapter. It has nothing to do with the TCP/IP address.

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LVM

Saturday, September 20th, 2014

LVM :- Logical Volume Manager and it’s a disk Management for Linux/UNIX Systems.

How To Check Linux Hardware Info

Saturday, July 5th, 2014
lscpu

Reports info about the cpu and processing units.

lshw

Reports detailed/brief info about multiple hardware units like cpu, memory, disk, network adapters etc.

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how to Compare between 2 files

Monday, March 3rd, 2014

how to comapre between 2 files to list the differences between them ???

there is a greate 2 commands which you can use them.

first command is

diff  FILE1  FILE2

and this command just display the difference between the 2 files.

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How to sync users and password between hosts on hacmp

Sunday, February 23rd, 2014

AIX has a wonderful method to synchronize the users and their passwords or any files you need to sync them between HACMP Nodes.

there is a command call “rdist”, this command used to transfer files between hosts and make them synced.

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uncompress files using jar command

Sunday, February 23rd, 2014

you can uncompressed zipping files using java, specially “jar” command:

 

to do that , try the following :

 

/usr/java6/bin/jar -xvf /tmp/test.zip

run levels description

Saturday, December 21st, 2013

The Following points shows the meaning of each run level :

  • on LINUX-UBUTNU/DEBIAN:

0 – halt
1 – single user
2 – multiuser (default)
3 – same as 2
4 – same as 2
5 – same as 2
6 – reboot Continue Reading…