Table of Contents back to table of contents Base OS back to section index LVM and JFS next page File Systems
feedback

LVM and JFS

Index
Information

Because LVM was designed to be used with partitioned direct access storage devices (i. e. hard disks primarily) - which are managed by the OS2DASD.DMD device management driver - there is a problem with removable media. Media which are formatted with the Super Floppy Disk format (Big Floppy, Large Floppy) cannot be handled correctly, because they do not have a partition table (otherwise equal to FAT16). If you allow LVM to commit changes when exiting the program, it will write to inserted removable media in SFD format causing data corruption! So please eject such media before allowing LVM to perform write operations!
After the application of the LVM update buildlevel 14.105, LVM handles "Big Floppy" media correctly.

Do not perform any operations with FDISK (e. g. of Warp 4) which write to storage media, after usage of LVM!

LVM makes the PARTFILT.FLT partition filter driver which was/is included with some third-party filesystems like FAT32 obsolete.

LVM Features

Features of the FDISK successor Logical Volume Manager (LVM):

  • partitioning of storage media
  • spanning over multiple partitions, which may be spread over different hard disks, to become so called logical volumes
  • dynamic expansion of logical volumes
  • permanent, freely selectable drive letters

Because of their structure, FAT and HPFS filesystems are less suitable for spanning. That is why the usage of JFS is recommended.

LVM with OS/2 Warp 4

Perform the following steps to add support for LVM to your OS/2 Warp 4 partition (requires FixPak XR*M013 or higher as prerequisite):

  1. copy the following files from the boot partition to the corresponding directories of the Warp 4 boot partition:
    • \OS2\BOOT\OS2DASD.DMD
    • \OS2\BOOT\OS2LVM.DMD
    • \OS2\DLL\LVM.DLL
    • \OS2\SYSTEM\LVM.MSG
    • \OS2\SYSTEM\LVMH.MSG
    • \OS2\LVM.EXE
  2. add this statement to the CONFIG.SYS right after the line containing OS2DASD.DMD:
    • BASEDEV=OS2LVM.DMD
IBM LVM Update
OS Date Files/Source Ver/Bld Lang. Notes
W5S, ACP, MCP, eCS 2006-06-13;
2006-06-23
technical document reserved (lvmupdt.exe);
lvm14105.exe reserved (eCS)
14.105 (XR0L002) English-US
Multilingual
restricted access - requirements:
W5S, ACP, MCP, eCS 2002-01-15 lvmupdt.exe 14.086 English-US updates files to Convenience Package 2 level, more current LVM files in Extended Partition Support
JFS Features

Some features of the Journaled File System:

  • recovery of the filesystem in seconds to minutes through logging of changes before execution (journaling)
  • cache up to 1 gigabytes (1/8 of installed memory ist default)
  • file and partition sizes up to 2 terabytes
  • up to 4 billion entries of directories and files
  • variable block sizes of 512, 1024, 2048, 4096 bytes

Because JFS can suffer from fragmentation, a command line utility to defragment a JFS volume is shipped with it.

A JFS-formatted partition is not bootable by default! eCo Software developed a bootable JFS which is available for users of eComStation.

IBM JFS Update
OS Date Files/Source Ver/Bld Lang. Notes
W5S, ACP, MCP, eCS 2006-06-15;
2006-06-25
technical document reserved (jfs.exe);
jfs14105.exe reserved (eCS)
14.105 English-US
Multilingual
restricted access - requirements:
W5S, ACP, MCP, eCS 2001-10-31 ftp access jfs1026.zip ÷ Generic JFS update; supersedes older jfs????.zip files
Bootable JFS for eComStation
OS Date Files/Source Ver/Bld Lang. Notes
eCS 2006-03-26 ecsjfs-20060326.zip reserved 20060326 Generic restricted access - requirements:
eCo Software's JRescuer/JUne for JFS
OS Date Files/Source Ver/Bld Lang. Notes
W5S, ACP, MCP, eCS 2006-01-15 JRescuerJune20060115.zip 2.30/2.20 Generic restore files from corrupted JFS volumes/deleted files
FreeJFS (OpenJFS)
OS Date Files/Source Ver/Bld Lang. Notes
W5S, ACP, MCP, eCS 2004-06-20 directory ÷ English-US more current build of some OpenJFS utils
W5S, ACP, MCP, eCS 2003-10-16 (2001-04-09) freejfs_1_1.zip 1.1 Generic codebase outdated;
requirements:
Links
Table of Contents back to table of contents Base OS back to section index LVM and JFS next page File Systems