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ORDS Connection Pool Fails to Start with 'IO Error: Unknown Host specified' When Using TNS Connection Type (Doc ID 2691358.1)

Last updated on SEPTEMBER 16, 2022

Applies to:

Oracle REST Data Services - Version 19.2 and later
Information in this document applies to any platform.


ORDS fails to start with IO Error if db.connectionType=tns is configured.


<timestamp> SEVERE IO Error: Unknown host specified ,|apex|pu|-<timestamp>,jdbc:oracle:thin:@<tnsAliasName>
<timestamp> WARNING The pool named: |apex|pu| is invalid and will be ignored: ORDS was unable to make a connection to the database. This can occur if the database is unavailable, the maximum number of sessions has been reached or the pool is not correctly configured. The connection pool named: |apex|pu| had the following error(s): IO Error: Unknown host specified


 Changed DB Connection type to TNS as follows:

<entry key="db.connectionType">tns</entry>
<entry key="db.tnsAliasName"><TNS alias name in tnsnames.ora></entry>
<entry key="db.tnsDirectory"><The directory location of tnsnames.ora file></entry>


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