Getting this error when Liberty starts up in a CICS 5.6 region.

In the liberty log this message appears:

Caused by: java.net.UnknownHostException: : : EDC9503I A non-recoverable error occurred when attempting to resolve the name or address.

It does not say what host name is causing the problem.

The server starts up and is usable despite this error

Hey Dan,

Is the LPAR in question connected to a DNS server and functional? I've seen similar errors when the hostname for the system is unresolvable. As you mentioned, without knowing what hostname its trying to resolve it's a bit of a mystery, but I have seen several implementations where the LPAR itself is either not connected to a DNS server or is connected to a DNS server that doesn't have an entry for whatever hostname the system considers itself to be. Some services do a hostname lookup on its own hostname and will fail, but still listen on the TCPIP stack specified. A way to prevent these errors, in cases where you either can't connect to a DNS server or add a DNS entry, is to add a name to the hosts file or IPNODES table that resolves the systems name.

Hope this helps some,

Steven

Getting this error when Liberty starts up in a CICS 5.6 region.

In the liberty log this message appears:

Caused by: java.net.UnknownHostException: : : EDC9503I A non-recoverable error occurred when attempting to resolve the name or address.

It does not say what host name is causing the problem.

The server starts up and is usable despite this error

Hey Dan,

Is the LPAR in question connected to a DNS server and functional? I've seen similar errors when the hostname for the system is unresolvable. As you mentioned, without knowing what hostname its trying to resolve it's a bit of a mystery, but I have seen several implementations where the LPAR itself is either not connected to a DNS server or is connected to a DNS server that doesn't have an entry for whatever hostname the system considers itself to be. Some services do a hostname lookup on its own hostname and will fail, but still listen on the TCPIP stack specified. A way to prevent these errors, in cases where you either can't connect to a DNS server or add a DNS entry, is to add a name to the hosts file or IPNODES table that resolves the systems name.

Hope this helps some,

Steven

Getting this error when Liberty starts up in a CICS 5.6 region.

In the liberty log this message appears:

Caused by: java.net.UnknownHostException: : : EDC9503I A non-recoverable error occurred when attempting to resolve the name or address.

It does not say what host name is causing the problem.

The server starts up and is usable despite this error

I suspect you're right. I wonder what out there is trying to do a hostname lookup and how you could possibly find out the emitter of the message... Looks like you've covered all of your bases because everything is functional. This may be a task for the CICS folks to track down if you don't believe it's associated to any user code, assuming its just something that comes out before any applications are running in the region.

Hey Dan,

Is the LPAR in question connected to a DNS server and functional? I've seen similar errors when the hostname for the system is unresolvable. As you mentioned, without knowing what hostname its trying to resolve it's a bit of a mystery, but I have seen several implementations where the LPAR itself is either not connected to a DNS server or is connected to a DNS server that doesn't have an entry for whatever hostname the system considers itself to be. Some services do a hostname lookup on its own hostname and will fail, but still listen on the TCPIP stack specified. A way to prevent these errors, in cases where you either can't connect to a DNS server or add a DNS entry, is to add a name to the hosts file or IPNODES table that resolves the systems name.

Hope this helps some,

Steven

Getting this error when Liberty starts up in a CICS 5.6 region.

In the liberty log this message appears:

Caused by: java.net.UnknownHostException: : : EDC9503I A non-recoverable error occurred when attempting to resolve the name or address.

It does not say what host name is causing the problem.

The server starts up and is usable despite this error

I suspect you're right. I wonder what out there is trying to do a hostname lookup and how you could possibly find out the emitter of the message... Looks like you've covered all of your bases because everything is functional. This may be a task for the CICS folks to track down if you don't believe it's associated to any user code, assuming its just something that comes out before any applications are running in the region.

Hey Dan,

Is the LPAR in question connected to a DNS server and functional? I've seen similar errors when the hostname for the system is unresolvable. As you mentioned, without knowing what hostname its trying to resolve it's a bit of a mystery, but I have seen several implementations where the LPAR itself is either not connected to a DNS server or is connected to a DNS server that doesn't have an entry for whatever hostname the system considers itself to be. Some services do a hostname lookup on its own hostname and will fail, but still listen on the TCPIP stack specified. A way to prevent these errors, in cases where you either can't connect to a DNS server or add a DNS entry, is to add a name to the hosts file or IPNODES table that resolves the systems name.

Hope this helps some,

Steven

Getting this error when Liberty starts up in a CICS 5.6 region.

In the liberty log this message appears:

Caused by: java.net.UnknownHostException: : : EDC9503I A non-recoverable error occurred when attempting to resolve the name or address.

It does not say what host name is causing the problem.

The server starts up and is usable despite this error

Well, no progress with getting any help from IBM.

Since we use z/OS under the ZD&T license, there is no real support for z/OS issues.

Can anyone suggest how this error can be traced so we can figure out what hostname is causing the error message during Liberty JVM startup?

I suspect you're right. I wonder what out there is trying to do a hostname lookup and how you could possibly find out the emitter of the message... Looks like you've covered all of your bases because everything is functional. This may be a task for the CICS folks to track down if you don't believe it's associated to any user code, assuming its just something that comes out before any applications are running in the region.

Hey Dan,

Is the LPAR in question connected to a DNS server and functional? I've seen similar errors when the hostname for the system is unresolvable. As you mentioned, without knowing what hostname its trying to resolve it's a bit of a mystery, but I have seen several implementations where the LPAR itself is either not connected to a DNS server or is connected to a DNS server that doesn't have an entry for whatever hostname the system considers itself to be. Some services do a hostname lookup on its own hostname and will fail, but still listen on the TCPIP stack specified. A way to prevent these errors, in cases where you either can't connect to a DNS server or add a DNS entry, is to add a name to the hosts file or IPNODES table that resolves the systems name.

Hope this helps some,

Steven

Getting this error when Liberty starts up in a CICS 5.6 region.

In the liberty log this message appears:

Caused by: java.net.UnknownHostException: : : EDC9503I A non-recoverable error occurred when attempting to resolve the name or address.

It does not say what host name is causing the problem.

The server starts up and is usable despite this error

Hi Dan,

I've reached out to a few IBMers to try and get an answer. I'll point them to this thread to respond. 

Thanks! 

Well, no progress with getting any help from IBM.

Since we use z/OS under the ZD&T license, there is no real support for z/OS issues.

Can anyone suggest how this error can be traced so we can figure out what hostname is causing the error message during Liberty JVM startup?

I suspect you're right. I wonder what out there is trying to do a hostname lookup and how you could possibly find out the emitter of the message... Looks like you've covered all of your bases because everything is functional. This may be a task for the CICS folks to track down if you don't believe it's associated to any user code, assuming its just something that comes out before any applications are running in the region.

Hey Dan,

Is the LPAR in question connected to a DNS server and functional? I've seen similar errors when the hostname for the system is unresolvable. As you mentioned, without knowing what hostname its trying to resolve it's a bit of a mystery, but I have seen several implementations where the LPAR itself is either not connected to a DNS server or is connected to a DNS server that doesn't have an entry for whatever hostname the system considers itself to be. Some services do a hostname lookup on its own hostname and will fail, but still listen on the TCPIP stack specified. A way to prevent these errors, in cases where you either can't connect to a DNS server or add a DNS entry, is to add a name to the hosts file or IPNODES table that resolves the systems name.

Hope this helps some,

Steven

Getting this error when Liberty starts up in a CICS 5.6 region.

In the liberty log this message appears:

Caused by: java.net.UnknownHostException: : : EDC9503I A non-recoverable error occurred when attempting to resolve the name or address.

It does not say what host name is causing the problem.

The server starts up and is usable despite this error

Getting this error when Liberty starts up in a CICS 5.6 region.

In the liberty log this message appears:

Caused by: java.net.UnknownHostException: : : EDC9503I A non-recoverable error occurred when attempting to resolve the name or address.

It does not say what host name is causing the problem.

The server starts up and is usable despite this error

The 'Caused by" is usually part of a call stack that would show what code is throwing the exception and what called it, etc.  That would, probably, help a lot in figuring out what host name it is trying to resolve.  Do you still have it?  

Getting this error when Liberty starts up in a CICS 5.6 region.

In the liberty log this message appears:

Caused by: java.net.UnknownHostException: : : EDC9503I A non-recoverable error occurred when attempting to resolve the name or address.

It does not say what host name is causing the problem.

The server starts up and is usable despite this error

The 'Caused by" is usually part of a call stack that would show what code is throwing the exception and what called it, etc.  That would, probably, help a lot in figuring out what host name it is trying to resolve.  Do you still have it?  

Getting this error when Liberty starts up in a CICS 5.6 region.

In the liberty log this message appears:

Caused by: java.net.UnknownHostException: : : EDC9503I A non-recoverable error occurred when attempting to resolve the name or address.

It does not say what host name is causing the problem.

The server starts up and is usable despite this error

The 'Caused by" is usually part of a call stack that would show what code is throwing the exception and what called it, etc.  That would, probably, help a lot in figuring out what host name it is trying to resolve.  Do you still have it?  

Getting this error when Liberty starts up in a CICS 5.6 region.

In the liberty log this message appears:

Caused by: java.net.UnknownHostException: : : EDC9503I A non-recoverable error occurred when attempting to resolve the name or address.

It does not say what host name is causing the problem.

The server starts up and is usable despite this error

I have also uploaded a more detailed "trace.log" file showing the error

The 'Caused by" is usually part of a call stack that would show what code is throwing the exception and what called it, etc.  That would, probably, help a lot in figuring out what host name it is trying to resolve.  Do you still have it?  

Getting this error when Liberty starts up in a CICS 5.6 region.

In the liberty log this message appears:

Caused by: java.net.UnknownHostException: : : EDC9503I A non-recoverable error occurred when attempting to resolve the name or address.

It does not say what host name is causing the problem.

The server starts up and is usable despite this error

Looking at the source for JsonLogHandler (https://github.com/OpenLiberty/open-liberty/blob/integration/dev/com.ibm.ws.logging/src/com/ibm/ws/logging/internal/impl/JsonLogHandler.java) it would appear we're doing this:

InetAddress.getLocalHost().getCanonicalHostName();

and from the call stack it looks like getLocalHost is the bit that is throwing the error.  
The doc for that says it throws an unknown host exception "if the local host name could not be resolved into an address." 
I don't know what could cause that though...

I have also uploaded a more detailed "trace.log" file showing the error

The 'Caused by" is usually part of a call stack that would show what code is throwing the exception and what called it, etc.  That would, probably, help a lot in figuring out what host name it is trying to resolve.  Do you still have it?  

Getting this error when Liberty starts up in a CICS 5.6 region.

In the liberty log this message appears:

Caused by: java.net.UnknownHostException: : : EDC9503I A non-recoverable error occurred when attempting to resolve the name or address.

It does not say what host name is causing the problem.

The server starts up and is usable despite this error

Does it say anywhere what the local host name is ?  (the one it is trying to resolve) 

------------------------------
Dan Kalmar

Original Message:
Sent: Mon April 03, 2023 08:16 AM
From: David Follis
Subject: EDC9503I A non-recoverable error occurred when attempting to resolve the name or address.

Looking at the source for JsonLogHandler (https://github.com/OpenLiberty/open-liberty/blob/integration/dev/com.ibm.ws.logging/src/com/ibm/ws/logging/internal/impl/JsonLogHandler.java) it would appear we're doing this:

InetAddress.getLocalHost().getCanonicalHostName();

and from the call stack it looks like getLocalHost is the bit that is throwing the error.  
The doc for that says it throws an unknown host exception "if the local host name could not be resolved into an address." 
I don't know what could cause that though...

------------------------------
David Follis
WebSphere z/OS and Java Batch Architect
IBM
Poughkeepsie NY
845-435-5462

Original Message:
Sent: Sun April 02, 2023 01:06 AM
From: Dan Kalmar
Subject: EDC9503I A non-recoverable error occurred when attempting to resolve the name or address.

I have also uploaded a more detailed "trace.log" file showing the error

------------------------------
Dan Kalmar

Original Message:
Sent: Fri March 31, 2023 09:49 AM
From: David Follis
Subject: EDC9503I A non-recoverable error occurred when attempting to resolve the name or address.

The 'Caused by" is usually part of a call stack that would show what code is throwing the exception and what called it, etc.  That would, probably, help a lot in figuring out what host name it is trying to resolve.  Do you still have it?  

------------------------------
David Follis
WebSphere Java Batch Architect
IBM
Poughkeepsie NY
845-435-5462

Original Message:
Sent: Sat February 18, 2023 03:08 PM
From: Dan Kalmar
Subject: EDC9503I A non-recoverable error occurred when attempting to resolve the name or address.

Getting this error when Liberty starts up in a CICS 5.6 region.

In the liberty log this message appears:

Caused by: java.net.UnknownHostException: : : EDC9503I A non-recoverable error occurred when attempting to resolve the name or address.

It does not say what host name is causing the problem.

The server starts up and is usable despite this error

------------------------------
Dan Kalmar
------------------------------

Looking at the source for JsonLogHandler (https://github.com/OpenLiberty/open-liberty/blob/integration/dev/com.ibm.ws.logging/src/com/ibm/ws/logging/internal/impl/JsonLogHandler.java) it would appear we're doing this:

InetAddress.getLocalHost().getCanonicalHostName();

and from the call stack it looks like getLocalHost is the bit that is throwing the error.  
The doc for that says it throws an unknown host exception "if the local host name could not be resolved into an address." 
I don't know what could cause that though...

I have also uploaded a more detailed "trace.log" file showing the error

The 'Caused by" is usually part of a call stack that would show what code is throwing the exception and what called it, etc.  That would, probably, help a lot in figuring out what host name it is trying to resolve.  Do you still have it?  

Getting this error when Liberty starts up in a CICS 5.6 region.

In the liberty log this message appears:

Caused by: java.net.UnknownHostException: : : EDC9503I A non-recoverable error occurred when attempting to resolve the name or address.

It does not say what host name is causing the problem.

The server starts up and is usable despite this error

Looking at the source for JsonLogHandler (https://github.com/OpenLiberty/open-liberty/blob/integration/dev/com.ibm.ws.logging/src/com/ibm/ws/logging/internal/impl/JsonLogHandler.java) it would appear we're doing this:

InetAddress.getLocalHost().getCanonicalHostName();

and from the call stack it looks like getLocalHost is the bit that is throwing the error.  
The doc for that says it throws an unknown host exception "if the local host name could not be resolved into an address." 
I don't know what could cause that though...

I have also uploaded a more detailed "trace.log" file showing the error

The 'Caused by" is usually part of a call stack that would show what code is throwing the exception and what called it, etc.  That would, probably, help a lot in figuring out what host name it is trying to resolve.  Do you still have it?  

Getting this error when Liberty starts up in a CICS 5.6 region.

In the liberty log this message appears:

Caused by: java.net.UnknownHostException: : : EDC9503I A non-recoverable error occurred when attempting to resolve the name or address.

It does not say what host name is causing the problem.

The server starts up and is usable despite this error