RE: ORA-28547 - "connection to server failed, probable Oracle Net admin error" when Database sessions touched 18,000

Date: Fri, 11 Jan 2008 01:35:01 +0530
Message-ID: <>

Thanks for the support sol

Do you mean that insufficient Number of Network Cards (1 only) & thus insufficient network thruput versus the high Trasactions' Load is the probable cause of the ORA-28547("connection to server failed, probable Oracle Net admin error") error when sessions gradually increase to 18,000?

NOTE - Additional Network cards will be added soon, whereafter the Listener processes will be setup on different network cards.


From: sol beach []
Sent: Thursday, January 10, 2008 7:28 AM To: VIVEK_SHARMA
Subject: Re: ORA-28547 - "connection to server failed, probable Oracle Net admin error" when Database sessions touched 18,000

Forgive me, but this configuration is daft from my perspective. 1) The Oracle listener ONLY comes into play for establishing the initial connection between a client & new DB session. 2) The NIC is single threaded. While it is servicing request for any 1 port, it can NOT be servicing any other traffic.

So I have to ask, what does having more than 1 listener on the same NIC buy you?

On Jan 9, 2008 4:38 PM, VIVEK_SHARMA <<>> wrote:


During a Benchmark Run as Number of Database sessions increased to 18000 following Error Occured:-

ORA-28547 "connection to server failed, probable Oracle Net admin error"

Qs Will increasing the Number of Listener processes help?

ACTION - Listener processes have been increased from 12 to 16. But need to check if the error re-occurs or is resolved.

Qs Could it be a Network bandwidth issue?

Currently all 16 Listener processes sit on the SAME ( 1 ) Network Card, but use different Port Numbers.

Database setup - Shared Server (MTS)

Oracle<> (NON-RAC)

Solaris 10

Will share any info needed.



$ oerr ora 28547:-

*Action: Check Oracle Net administration in the following ways:

//           --  When using TNSNAMES.ORA or an Oracle Names server, make sure

// that the client connection to the ORACLE server uses
// the correct service name or SID.
// -- Check LISTENER.ORA on the connection end point's host machine
// to assure that this service name or SID refers
// to the correct server.
// -- Confirm in TNSNAMES.ORA or the equivalent service definition
// that the connect string does NOT contain (HS=).
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