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Step by Step - Configure Direct NFS Client (DNFS) on Linux (Doc ID 762374.1)

Last updated on OCTOBER 22, 2023

Applies to:

Oracle Database Cloud Schema Service - Version N/A and later
Oracle Database Exadata Express Cloud Service - Version N/A and later
Gen 1 Exadata Cloud at Customer (Oracle Exadata Database Cloud Machine) - Version N/A and later
Oracle Database Cloud Exadata Service - Version N/A and later
Oracle Database Backup Service - Version N/A and later
Generic Linux


The purpose of this document is to provide information about the Direct NFS client and Step by Step to configure Direct NFS client.

Note :-The following steps are purely provided for evaluative and educational purpose only.Any issues with configuring the NFS server/client on Linux ie PART A ,you need to contact your Vendor.Oracle will not provide support/troubleshoot PART A.


The DNFS Guide says to enable the init.ora param filesystemio_options to enable direct I/O support.
Doing this, all DB access to all files will be via DIO.
There is no way to only enable direct IO for certain files and exclude others.
So ensure ALL the places where are located your database files (including pfile/spfile, logs,....) are configured to accept Direct IO.

Direct NFS does not depend on the value of filesystemio_options. Direct NFS always issues async and direct I/O as it does not depend on OS support. However, since we can always fall back to the OS NFS client in case of mis-configuration - as a precaution - set filesystemio_options to 'directio' or 'setall' if the OS supports it.


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