Re: TNS-12541: TNS:no listener

From: Woody McKay <>
Date: Wed, 1 Nov 2017 13:02:29 -0400
Message-ID: <>

Hi all,

This is resolved. Found out that SAML was being used and it was creating numerous connections for each customer DB connection. I keystore cache was created that relieved the pressure.

tnsping saw delays up to 3000ms and many time "no listener" yet listener was continuously up.

AWR show logins per second of 400+

Found a perl script that mined the listener.log for connections per minute that made a cool Excel graph the leadership team could read.

Oracle support told me that the listener couldn't handle more than 20 connections per second and to create additional listeners if needed.

I told the support and app dev teams of the connection rate and they hunted till they found the SAML issue.


On Tue, Oct 31, 2017 at 12:03 PM, Bill Ferguson <> wrote:

> Hi Woody,
> Check the event log on the Windows server. This sometimes gives a bit more
> useful information. One possible explanation might be with the password
> having expired? I've had this problem a few times on Windows and the error
> messages are terrible, so I can't remember exactly what an Error 61 is, but
> hopefully there is a better error message in the event log. Have the system
> Admin check the Event Viewer. From there (it's been so long I can't
> remember exactly), I think it is "Windows Logs" and then "Application".
> Hope this helps,
> Bill Ferguson
> On Thu, Oct 26, 2017 at 8:08 AM, Woody McKay <>
> wrote:
>> Hello all,
>> Got a production server that has been having listener problems this week,
>> each morning. Hosted at rackspace.
>> lsnrctl status some times works and other times gives no listener error.
>> Windows event log shows the listener last came up yesterday, yet lsnrctl
>> show it available and not available this morning.
>> The listener.log shows no errors, only established connections.
>> The listener log grows fast. Connections to DB were about 300, with AWR
>> showing a login rate of about 136/second.
>> Earlier in the morning, when everything worked fine, the login rate was
>> 81/second.
>> The DB alert log shows no errors.
>> Here is the status error:
>> LSNRCTL> status ncdb226
>> Connecting to (ADDRESS=(PROTOCOL=TCP)(HOST=
>> TNS-12541: TNS:no listener
>> TNS-12560: TNS:protocol adapter error
>> TNS-00511: No listener
>> 64-bit Windows Error: 61: Unknown error
>> I can't figure out what this means: 64-bit Windows Error: 61: Unknown
>> error
>> All of this worked fine last week. Could there be a windows port time out
>> or something?
>> Thoughts?
>> Woody
> --
> -- Bill Ferguson



Received on Wed Nov 01 2017 - 18:02:29 CET

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