OA49605: Z/OS NFS SERVER DOESN'T RELEASE SPACE IN ZFS WHEN AIX CLIENT ISSUES RM (REMOVE) TO FILES ON REMOTE MP IN ZFS.

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• z/OS NFS Server doesn't release space in zFS when AIX client
  issues rm (remove) to files on remote MP in zFS.
  The reason seems to be that ref counter in Fileblock (H_FB) for
  such files become negative.
  
  Before this occured customer applied following NFS maintenance
  via RSU1509:
  UA76608 (OA46635), UA76675 (OA47225), UA76677 (OA47122),
  UA76679 (OA45165), UA76760 (OA47000), UA76806 (OA47318),
  UA77115 (OA47355), UA77462 (OA47224), UA77639 (OA47777),
  UA75030 (OA46304), UA76382 (OA46679), UA76610 (OA47177),
  UA78999 (OA48334)
  
  NFS Server trace showed following Fileblock was marked removed
  during AIX remove operation:
  
  GFSA4URM,759  h4_remove()  marked Fb(2b770220) as removed
  
  DUMP showed that above Fb(2b770220) has a negative count:
  
  2B7702DC: H_FB+x'BC' count = x'FFFFFFFF' = -1 negative
  2B7702D8: H_FB+x'B8' h_ref = x'A0'       (delete=ON,
  hfb_nameLock=ON).
  
  2B770220: 00000000 C86DC6C2 00000000 00000000 | ....H_FB........
  2B770230: LENGTH(X'10')--All bytes contain X'00'
  2B770240: 00000000 2B769B80 5673F58D 00000000 | ..........5.....
  2B770250: LENGTH(X'20')--All bytes contain X'00'
  2B770270: 00000000 00000000 A385A2A3 F1000000 | ........test1...
  2B770280: LENGTH(X'50')--All bytes contain X'00'
  2B7702D0: 00000000 00000000 A0000000 FFFFFFFF | ................
  2B7702E0: LENGTH(X'40')--All bytes contain X'00'
  2B770320: 04F07740 00003853 00002A3A 00000F6C | .0. ...........%
  2B770330: 00000000 0E4F0000 295BD860 00000001 | .....|...$Q-....
  2B770340: 00000008 00140001 00000000 030001C0 | ...............{
  2B770350: 00000F6C 00000F6C 00002A3A 00000000 | ...%...%........
  2B770360: 00000000 00000001 00000000 00000000 | ................
  2B770370: LENGTH(X'30')--All bytes contain X'00'
  2B7703A0: 2B691900 C6D9C5C5 009BA030 2B76F000 | ....FREE......0.
  2B7703B0: 006300A2 5673F57D 00000000 00000160 | ...s..5'.......-
  

Local fix

• circumvention to release the space in zFS:
  
  - remount the NFS MP
  - restart z/OS NFS Server
  - bounce the server to second LPAR
  

Problem summary

• ****************************************************************
  * USERS AFFECTED: All z/OS Network File System Server users.   *
  ****************************************************************
  * PROBLEM DESCRIPTION: 1. NFS removes not freeing space in zFS *
  ****************************************************************
  * RECOMMENDATION:                                              *
  ****************************************************************
  1. Properly manage file serialization for files available
     only in public mounts.
  

Problem conclusion

• 1. Properly manage file serialization for files available
     only in public mounts.
  

Temporary fix

Comments

APAR Information

• APAR is sysrouted FROM one or more of the following:

• APAR is sysrouted TO one or more of the following:

  UA81371 UA81372 UA81373

Modules/Macros

• GFSAFHFS GFSAMCMN GFSAZHFS GFSAZLOC GFSAZMAI
  GFSAZMSC GFSA4ULU GFSA4UOP GFSA4URM
  

Fix information

• Fixed component name

  NETWORK FILE SY

• Fixed component ID

  5695DF121

Applicable component levels

• RD1N PSY UA81371

     UP16/05/04 P F605

• R21N PSY UA81372

     UP16/05/04 P F605

• R22N PSY UA81373

     UP16/05/04 P F605

Fix is available

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