jfs2

[Shivkumar]

Hi,

Are the commands for JFS2 very different than LVM ? Is JFS2 an ehanced version of LVM ?

Thanks,
Shiv

[Arunvijai_4 · Accepted solution]

Hi Shiv,

JFS2 is Journaling File system used in IBM AIX 5.x where as LVM is Logical Volume Manager. I dont think you can compare LVM and JFS2. Commands are different for creating JFS2,

# crfs -v jfs2 -g rootvg -m /test -A no -a size=10000

You can see the history here, http://en.wikipedia.org/wiki/JFS#History

-Arun

[Raj D.]

Shiv ,

JFS and JFS2 are used in AIX operating sstem , also the hp-ux version of JFS is called VxFS veritas filesystem. And JFS/JFS2/VxFS all are used with LVM.


AIX Journaled File Systems and Veritas File System :

The purpose of a file system is simply to hold data. UNIX file systems have had a fairly common evolution from their base of Berkeley Software Distribution. It was called the Berkeley Fast File System, which eventually became the UNIX industry standard known as the UNIX File System (UFS). IBM introduced its UNIX file system as the Journaled File System (JFS) with the initial release of AIX Version 3.1. It has now introduced a second file system that is to run on AIX systems called Enhanced Journaled File System (JFS2), which is available in AIX Version 5.0 and later versions. Veritas introduced the Veritas File System (VxFS) that is sold to run as a standalone product, or with Veritas Volume Manager (VxVM) or other volume managers. VxFS can optimize I/O and is designed to work with standard volume managers. JFS and JFS2 are designed to run on the AIX Logical Volume Manager (LVM) that is built into the base of the AIX operating system.


Functional Differences:
Functional Differences
Functional differences between JFS, JFS2, and VxFS include the following:


Journaling
I-nodes
Caching
Data integrity
Online File System Resizing
Online Defragmentation
------------------------------


Cheers,
Raj.

[Raj D.]

Shiv,

Check this link for some more details:

http://www-03.ibm.com/servers/aix/products/aixos/whitepapers/jfs_vfs.html



hth,
Raj.

[Shivkumar]

Looks like HPUX has jfs online product. right ??
I got confused between aix and hpux journaling file system.

Regards,
Shiv

[Arunvijai_4]

Hi Shiv,

JFS in HP-UX is known as Veritas FS (VXFS). If you want onlineJFS for 11i, you can download it from here,

http://h20293.www2.hp.com/portal/swdepot/displayProductInfo.do?productNumber=BASEVXFS

-Arun

[Raj D.]

Shiv,

Though you can download the Base VxFS 3.3 product , to use the Full VxFS 3.3 (also known as Online JFS ) you have to purchase it with HP Product Number B3929CA.


1.Base --> VxFS 3.3 ,also known as JFS 3.3 [ Base VxFS]

2. Full --> VxFS 3.3 ,also Known as OnlineJFS 3.3 [ To be purchase separately.]


Cheers,
Raj.

[Darrel Louis]

Shiv,

When installing the Online JFS software don't forget to install the JFS/LVM patches after the installation.

Darrel