The HMGR0027W message indicates the IP address on the physical server is mapped to two different host names. Also, the DCS_UNICAST_ADDRESS port configuration on the JVM has a value of either the IP address or an asterisk (*).
To resolve the problem, set the DCS_UNICAST_ADDRESS port value to the desired host name value instead of the IP address or asterisk. Most likely this will need to be performed on all JVMs that are on the server(s) on which the IP address is mapped to two host names. In your administrative console click on Servers > Server Types > WebSphere application servers > (Your_Server_Name) > Ports.
Afterward, clear the OSGi and JVM class caches by running the osgiCfgInit and clearClassCache commands as described in the following document:
How to clear the WebSphere class caches
https://www.ibm.com/support/pages/node/212877
It may also help to remove the contents of the 3 profile temporary directories:
- <profile_root>/wstemp/
- <profile_root>/temp/
- <profile_root>/config/temp/
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Marcio D'Amico
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Original Message:
Sent: Fri February 23, 2024 09:30 AM
From: Sai Vamsi Gude
Subject: During application server startup, the following HMGR0027W is written to the SystemOut.log file...
[2/19/24 17:04:31:572 EST] 00000001 HostNameMap E HMGR0027W: A duplicate host to IP Address mapping has been detected. IP Address <IPAddress_Value> has a mapping to host names <Hostname_1> and <Hostname_2>.
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Sai Vamsi Gude
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