Open System Services Management and Operations Guide (G06.30+, H06.08+, J06.03+)

• Catalog file volume (CATALOG attribute)
• OSS file-system mount point (MNTPOINT attribute)
• OSS name server identity (NAMESERVER attribute)
• OSS SEEP protection (SEEPPROTECTED attribute)
NOTE: OSS SEEP is supported beginning with the J06.15 and H06.26 RVUs. For details
of OSS SEEP, see “Using an OSS Security Event-Exit Process (SEEP)” (page 231).
To change any of these attributes, change the appropriate value in the ZOSSFSET file by using
the SCF ALTER FILESET command.
Changes made to the DESIREDSTATE, FSCKCPU, and REPORT attributes take effect immediately.
Changes made to any other attribute require the following additional steps before they can take
effect:
• To change any of the AUDITENABLED, RESTRICTEDACCESS, BUFFERED, FTIOMODE,
MAXINODES, NORMALIOMODE, POOL, READONLY, NFSPERMMAP, NFSPOOL, or
NFSTIMEOUT attributes, apply the change to the fileset using the SCF CONTROL FILESET
command with the SYNC option.
Changes to FTIOMODE or NORMALIOMODE only apply to files opened after the new attribute
value takes effect; already opened files are not affected.
Changes to any attribute made by the ALTER FILESET command take effect when the fileset
restarts, regardless of whether CONTROL FILESET, SYNC is used.
• To change any of the CATALOG, MNTPOINT, or NAMESERVER attributes:
1. If the fileset is started, stop it by using the SCF STOP FILESET command, as described
under “Stopping (Unmounting) a Fileset” (page 151).
2. Restart the fileset using the SCF START FILESET command.
All changes to these attributes made by the ALTER FILESET command take effect when
the fileset restarts.
Changing Fileset Input/Output Fault Tolerance
The value used for the FTIOMODE and NORMALIOMODE options affect application performance
and fault tolerance. Fault tolerance for files opened without using the O_SYNC bit is controlled by
the NORMALIOMODE option setting; fault tolerance for files opened using the O_SYNC bit is
controlled by the FTIOMODE option setting.
The FTIOMODE settings are a subset of the NORMALIOMODE settings. The setting used for the
FTIOMODE attribute of a specific fileset must have a fault-tolerance level at least as high as that
of the NORMALIOMODE attribute setting for the fileset. The attribute settings are, from highest to
lowest fault tolerance and from lowest to highest performance:
UNBUFFEREDCP
DP2BUFFEREDCP
OSSBUFFEREDCP
DP2BUFFERED
OSSBUFFERED
The behaviors associated with these levels of fault tolerance are shown in Table 10.
Table 10 Effects of File I/O Fault-Tolerance Attribute Settings
ResultsScenariosSetting
Transparent recoveryApplication fails
with possible loss of multiple buffered
Single DP2 processor failureSystem
failure (or double DP2 processor
failure) Application processor failure
OSSBUFFEREDCP
write requests if failure occurs before
Reconfiguring a Fileset 153