I/O stuck or unreported data inconsistencies on CIFS socket writes

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Environment

SUSE Linux Enterprise Server 10 Service Pack 2
SUSE Linux Enterprise Server 10 Service Pack 1
SUSE Linux Enterprise Server 9

Situation

Customers running the CIFS client may experience unreported data inconsistencies in the following conditions:

Running the CIFS client with caching enabled (default option) may experience data miscompares over stressed or congested networks.
Running the CIFS Client with the 'forcedirectio' option set and with applications using the 'O_APPEND' option.

Systems with CIFS Client enabled may experience one of these problems depending on the write option used and the version/release of Linux OS.

Resolution

The fix currently available for both of these scenarios is to migrate to a recent level of SUSE Linux Enterprise Server 10 SP2 or SUSE Linux Enterprise Server 9 SP4and run the default option of write cache only.

The fix to enable CIFS client to run 'forcedirectio' with applications doing 'O_APPEND' is available as a Maintenance Web update for:

SLES 9 SP4 with an updated kernel which has version 2.6.5-7.314 or above.
SLE(S/D) 10 SP2 with an updated kernel with version 2.6.16.60-0.31 or above.

Disclaimer

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