error message in alert.log after dnfs is enabled for a database...

Database Alert Log entries: Direct NFS: Failed to set socket buffer size.wtmax=[1048576] rtmax=[1048576], errno=-1 (Doc ID 1352886.1)    

   

Applies to:

Oracle Database - Enterprise Edition - Version 11.2.0.2 and later

Information in this document applies to any platform.

Symptoms

Database alert log shows these 'Direct NFS: Failed to set socket buffer size.wtmax=[1048576] rtmax=[1048576], errno=-1' entries:

alert_ORCL.log

~~~~~~~~~~~

...

Mon Aug 08 21:04:00 2011

Adjusting the default value of parameter parallel_max_servers

from 320 to 185 due to the value of parameter processes (200)

Starting ORACLE instance (normal)

...

Starting up:

Oracle Database 11g Enterprise Edition Release 11.2.0.2.0 - 64bit Production

...

Oracle instance running with ODM: Oracle Direct NFS ODM Library Version 3.0

...

Mon Aug 08 21:05:19 2011

Direct NFS: Failed to set socket buffer size.wtmax=[1048576] rtmax=[1048576], errno=-1        <-- here

...

Cause

tcp_max_buf: is set too small.

Solution

The error can be fixed by increasing the value of tcp_max_buf:

# /usr/sbin/ndd -set /dev/tcp tcp_max_buf 1056768

To display its value:

# /usr/sbin/ndd /dev/tcp tcp_max_buf

Also check what are tcp_xmit_hiwat and tcp_recv_hiwat set to and if set low, see if increasing these helps:

# /usr/sbin/ndd -set /dev/tcp tcp_xmit_hiwat 1056768

# /usr/sbin/ndd -set /dev/tcp tcp_recv_hiwat 1056768

To display their values:

# /usr/sbin/ndd /dev/tcp tcp_xmit_hiwat

# /usr/sbin/ndd /dev/tcp tcp_recv_hiwat