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Listener Startup or Connections Hang in 11g (Doc ID 803838.1)

Last updated on FEBRUARY 20, 2019

Applies to:

Oracle Net Services - Version to [Release 11.1 to 12.1]
HP-UX PA-RISC (64-bit)
Generic UNIX


Beginning with Oracle RDBMS release 11g, the listener functionality bypasses the /etc/hosts file when resolving hostnames to IPs and instead query the DNS server.
This can introduce some delay in establishing a connection to a remote host compared with 10g.

SQL*Plus and tnsping show this behavior but this delay can appear also when opening a dblink or anytime TCP connections are established by the Oracle Network layer.

This happens even if  Name Server Switch configuration (nsswitch) specifies the hosts file prior to dns lookups:



Nothing was changed in the configuration of the OS, only the upgrade from Oracle 10g to 11g was done.


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