How to resolve TNS:Connection closed error?
Posted by Pavan DBA on April 25, 2012
Today I faced some issue regarding listener startup and want to share this info with you folks…
I got an email from users saying they are unable to connect to one of the production server. They are getting “NO LISTENER” message. So, its clear from this that listener could have been shutdown.
I logged in and checked the listener status using both “lsnrctl status” command and “ps -ef | grep tns” command. Both of the commands didn’t given any posivitive result.
So I started the listener with the below command and got error as this…
[oracle@dbserver1 admin]$ lsnrctl start LISTENER
LSNRCTL for Linux: Version 10.2.0.1.0 – Production on 25-APR-2012 18:16:24
Copyright (c) 1991, 2005, Oracle. All rights reserved.
Starting /u01/ora10g/bin/tnslsnr: please wait…
TNS-12537: TNS:connection closed
TNS-12560: TNS:protocol adapter error
TNS-00507: Connection closed
Linux Error: 29: Illegal seek
The problem is identified as a line is missing in /etc/hosts file (mine is a Linux server). I added below line and problem solved
127.0.0.1 localhost.localdomain localhost
So, whenever you hit with the above error (Illegal Seek), please check hosts file and add the above line which will solve the issue……
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Sergio Carvalho said
Thanks a Lot! It worked for me too…
Pavan DBA said
happy to hear that
Kanchan said
Thanks.worked for me !!!
Dilip (Kanna) said
Pavan –
One of our servers got restarted. We already had below entry in /etc/hosts file.
127.0.0.1 localhost.localdomain localhost
Yet the listener failed to come up with the error mentioned in the post.
I had to do “export LD_BIND_NOW=1” and then restart the listener. Just in case anybody else faces this issue.
Thanks –
Pavan DBA said
thanks for the info.
Aneel Ahmed said
Thanks a lot; it really helped….
Pavan DBA said
great to hear that
afsar said
thtanks brothter
Mohammad Shadab Ashraf said
Great… Thanks for sharing