IBM Support

cannot use a minus '-' sign with smitty cspoc panels to decrease a jfs2 filesystem size in a PowerHA cluster

Troubleshooting


Problem

When trying to decrease (shrink) the size of a PowerHA shared filesystem using smit panels; if a minus '-' sign is used, the administrator may receive the following error message:
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Command: failed stdout: yes stderr: no

Before command completion, additional instructions may appear below.

Error: Only jfs2 file systems may be reduced in size.
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

Symptom

 

Cause

A coding error at certain levels of PowerHA is the underlying cause of this condition

Environment

The error can occur when running AIX with the following versions of PowerHA
v7.2.9.0  /  v7.2.9.1 / v7.2.10.0

PowerHA v7.2.8.x and lower does not exhibit the problem 

 

 

Diagnosing The Problem

Lab testing results follow:
NOTE: filesystem ha3fs2 is type jfs2

 

We start with ha3fs2 having a total of 11 PPs in size
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
(0) [HAES7290/AIX73-04 @ labbox47] /

lsvg -l ha3vg

ha3vg:
LV NAME TYPE LPs PPs PVs LV STATE MOUNT POINT
ha3lv1 jfs 11 11 1 open/syncd /ha3fs1
ha3lv2 jfs2 11 11 1 open/syncd /ha3fs2
ha3lvraw raw 10 10 1 closed/syncd N/A
log3lv1 jfslog 1 1 1 open/syncd N/A
log3lv2 jfs2log 1 1 1 open/syncd N/A

 

(0) [HAES7290/AIX73-04 @ labbox47] /

lsvg -L ha3vg

VOLUME GROUP: ha3vg VG IDENTIFIER: 00f87c4b00004c000000019c8c7350e1
VG STATE: active PP SIZE: 8 megabyte(s)
VG PERMISSION: read/write TOTAL PPs: 1269 (10152 megabytes)
MAX LVs: 256 FREE PPs: 1235 (9880 megabytes)
LVs: 5 USED PPs: 34 (272 megabytes)
OPEN LVs: 4 QUORUM: 2 (Enabled)
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

 

# smitty cspoc >  Storage >   File Systems >    Change / Show Characteristics of a File System >    then choose ha3fs2

Final screen:
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Change/Show Characteristics of a Enhanced Journaled File System

Type or select values in entry fields.
Press Enter AFTER making all desired changes.

Volume group name ha3vg
Resource Group Name rg1

  • Node Names labbox47,hacmp48
  • File system name /ha3fs2
    NEW mount point [/ha3fs2] /
    SIZE of file system
    Unit Size 512bytes +
    Number of Units [180224] #
    Mount GROUP []
    Mount AUTOMATICALLY at system restart? no +
    PERMISSIONS read/write +
    Mount OPTIONS [] +
    Start Disk Accounting? no +
    Block Size (bytes) 4096
    Inline Log? no
    Inline Log size (MBytes) [0] #
    Extended Attribute Format [v1]
    ENABLE Quota Management? no +
    Allow Small Inode Extents? [yes] +
    Logical Volume for Log yes +
    Encrypted File System no

++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

 

We know the filesytem is 11 PPs in size from the output of lsvg -l

We now see that that 11 PPs = 180224 units of 512bytes
so 1 pp   =    180224 / 11    =   16384

 

We try to reduce the FS size in smit by 1 PP with -16384
+++++++++++++++++++++++++++++++++++++++++++++++++++++++

  • File system name /ha3fs2
    NEW mount point [/ha3fs2] /
    SIZE of file system
    Unit Size 512bytes +
    Number of Units [-16384] #
    Mount GROUP []

++++++++++++++++++++++++++++++++++++++++++++++++++++++++

 

But, we receive the following error from smit
++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Command: failed stdout: yes stderr: no

Before command completion, additional instructions may appear below.

Error: Only jfs2 file systems may be reduced in size.
++++++++++++++++++++++++++++++++++++++++++++++++++++++++

Resolving The Problem

An immediate resolution is to calculate the desired smaller size of the filesystem and enter that into the smit panel.

EXAMPLE:
 

Reduce the filesystem size 1 PP, by setting a new total value for the FS
-Total current units 180224
-reduce by 1 PP of units 16384
-equals 163840 new total units
"180224 - 16384 = 163840"

In smit panel do:
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

  • File system name /ha3fs2
    NEW mount point [/ha3fs2] /
    SIZE of file system
    Unit Size 512bytes +
    Number of Units [163840]

+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

 

Receive the OK from smit
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Command: OK stdout: no stderr: no
Before command completion, additional instructions may appear below.
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++


NOTE: IBM development anticipates releasing a permanent code fix for this issue in future service packs.

A permanent apar code fix for this issue is planned (though not assured) for the following fix releases when available:

SP 2 for PowerHA v7.2.9  ( v7.2.9.2)

SP 1 for PowerHA v7.2.10 (v7.2.10.1)

 

SUPPORT:

More assistance is available by opening a case for software under warranty or with an active and valid support contract.  The technical support specialist assigned to your case confirms the steps were completed.

   -For electronic support, visit the IBM Support Community:
     https://www.ibm.com/mysupport
   -If you require telephone support, visit the web page:
      https://www.ibm.com/planetwide/

 

 Provide a good description of your issue and refer to this document:
 for a PowerHA cluster collection please use  # snap -e

     Working with IBM AIX Support: Collecting snap data

 

 Upload all of the details and data to your case

   -You can attach files to your case in the IBM Support Community
   -Or upload to the IBM Enhanced Customer Data Repository
      https://www.secure.ecurep.ibm.com/app/upload_sf

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Document Information

Modified date:
03 April 2026

UID

ibm17268537

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