On some systems you will find still JFS fs. Although this is not bad, JFS2 is more scalable and has some advantages over JFS. In order to update JFS to JFS2 follow this instruction found here:
JFS to JFS2 Conversion steps
1. Perform a mksysb backup of the system (using either NIM, DVD-RAM or tape). This step performs two important actions – it runs the mkszfile command (which updates /image.data) and also provides the ability to undo the JFS to JFS2 conversion.
/bosinst.data /image.data /etc/filesystems
3. Modify these 3 files as follows:
Look for the following 2 lines
ENABLE_64BIT_KERNEL = Default CREATE_JFS2_FS = Default
Change them to read:
ENABLE_64BIT_KERNEL = yes CREATE_JFS2_FS = yes
In the lv_data section of the file – change all occurrences of the string “jfs” to “jfs2”
In the fs_data section of the file – change each new JFS2 filesystem stanza from:
fs_data: FS_NAME= /usr FS_SIZE= 7340032 FS_MIN_SIZE= 3714768 FS_LV= /dev/hd2 FS_FS= 4096 FS_NBPI= 4096 FS_COMPRESS= no FS_BF= false FS_AGSIZE= 8
fs_data: FS_NAME= /usr FS_SIZE= 7340032 FS_MIN_SIZE= 3714768 FS_LV= /dev/hd2 FS_JFS2_BS= 4096 FS_JFS2_SPARSE= yes FS_JFS2_INLINELOG= no FS_JFS2_SIZEINLINELOG= 0 FS_JFS2_EAFORMAT= v1 FS_JFS2_QUOTA= no FS_JFS2_DMAPI= no FS_JFS2_VIX= no
For all of the rootvg filesystems – change occurrences of the string “jfs” to “jfs2”
4. Create another mksysb of the system but ensure that the -i flag is not used for the mksysb command. (TIP: If the -i flag is used then mkszfile will run again and will erase all of the custom changes made to the /image.data file)
5. Restore this mksysb (created in step 4) on the system and when the system comes up all of the rootvg filesystems will now be using JFS2 (run the mount command to confirm).