Being DBA we all are aware that we must have knowledge of OS level too because Database not just runs over the only one OS. In a different organization, we have a different OS. Being a part if IT we understand that different OS environment has a different parameter. We have to set them.

Today let’s have look on this.


TNS-12547: TNS:lost contact
TNS-12560: TNS:protocol adapter error
TNS-00517: Lost contact
Linux Error: 104: Connection reset by peer


TNS-12537: TNS:connection closed
TNS-12560: TNS:proto adapter error
TNS-00507: Connection closed
Linux Error: 29: Illegal seek


We must make sure the following loopback entries exist in /etc/hosts file. If the Operating system configured with IPV6 then you need to add the second line as well. Start the listener after adding the following entries. For more information please check Doc ID 960152.1 from Oracle Support. localhost.localdomain localhost

::1 localhost6.localdomain localhost6

Today’s thought

If you light a lamp for someone else, it will also brighten your path. —Buddha

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