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How to Resolve host and listener DNS lookup failures like ORA-12541 an ORA-12545 (Doc ID 743302.1)

Last updated on JANUARY 19, 2023

Applies to:

APM - Application Performance Management - Version 4.5.1 to [Release 4.5 to 12.1]
Oracle Database - Enterprise Edition - Version to [Release 11.2]
Information in this document applies to any platform.


The database used by RUEI depends on the DNS server. When the DNS lookup fails, RUEI is not able to access the database. This often results in errors such as:

This document shows how one can see if the there is a difference between the local host settings and the DNS settings.
Also when RUEI is implemented in an environment that does not have a DNS server this document provides useful pointers.



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In this Document
 Making sure the host name on the server is the same as on the DNS server
 Making sure the host name is correctly setup on the local system, by-passing the DNS server (or when there is no DNS Server)

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