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Description

Originally, MID Servers were bundled with Oracle's Java Runtime Environment (JRE). ServiceNow MID Servers included our own OpenJDK based JRE build from Madrid onward. This JRE has been what all MID Server-related release testing has been done with since. Since London Patch 8 and Kingston Patch 14b Hot Fix1, the same OpenJDK JRE is tested with and included in those older versions, and can also be used with previous London and Kingston MID Servers. From Paris, the bundled Java 8 OpenJDK will be updated to a more recent patch with every major release. 

The bundled JRE does not have to be used. You may have a requirement to use the latest Java 8 patch or Java 11 instead, for security reasons, or because you need to customise the JRE. You may also need an external JRE in order to preserve cacerts or other JRE settings from being overwritten when the bundled JRE is automatically upgraded. As of the Orlando release, MID Server officially documents that it supports all Oracle and OpenJDK JREs of Java 8 (patch 161 and above) and Java 11. If there is a problem running ServiceNow features and code on a MID Server with one of those non-bundled JREs then it will be treated as a product defect and we will try to provide a workaround or fix.

The following are known problems in pre-Quebec versions, and may already be fixed:

MID Server Installer Java Runtime
 <=Kingston

Oracle 1.8.0_152 JRE (8u152) is Supported and Distributed with the MID Server installer. Previously releases included 8u60, 8u40, 6u45 & 6u14 and were the 'supported version' at the time, and would have been upgraded along with the MID Server. 
Kingston Patch 14 was the final Patch to include an Oracle JRE.

Kingston Patch 14b HotFix1 included the OpenJDK 1.8.0_181 JRE, as used in Madrid.

Kingston Patches 0-13, and Patch 14, 14a, can replace the Oracle JRE with our OpenJDK using:
KB0745163 MID Server download packages for installing OpenJDK on Windows and Linux hosts

London 

No JRE is included in the full Installer ZIP file for London Patch 7 and below.
The minimum supported Oracle JRE is version 1.8.0_152 or higher Java 8 family. Customers had to install this first as per our docs and would therefore have to accept the licence agreement for the free Oracle Java SE 8 JRE to do that in their own name. Oracle no longer support this version though.

However, if the MID Server was installed <=Kingston, then an upgraded London MID Server will continue to use the Oracle JRE originally installed by ServiceNow. 

London Patch 8 and later includes the OpenJDK 1.8.0_181 JRE, as used in Madrid. 

Users of London Patches 0-7 can replace the Oracle JRE with our OpenJDK using these steps:
KB0745163 MID Server download packages for installing OpenJDK on Windows and Linux hosts

Customers who are using their own Oracle JRE, external to the agent folder, can switch back to using OpenJDK using these steps :
KB0719389 Switching the MID Server from an existing Java Runtime Environment (JRE) to the OpenJDK provided by ServiceNow

Madrid /
New York /
Orlando

A ServiceNow build of OpenJDK 1.8.0_181 JRE is Supported and Included. 
MID Servers installed before Madrid that are still using the Oracle JRE will have it replaced by the OpenJDK JRE.

The last versions to include 1.8.0_181 were Madrid Patch 10, New York Patch 7 and Orlando Patch 2. 

Paris /
Orlando Patch 3 /
New York Patch 8

OpenJDK 1.8.0_231 will be included in Paris, and that has already been back-ported to the current Orlando and New York Patches. (1.8.0_231-sncmid1)

New York Patch 8 and Orlando Patch 3 and later include 1.8.0_231. No Madrid patch included this version.

Windows x86-64mid-jre.newyork-06-26-2019__patch8-04-01-2020_04-10-2020_1401.windows.x86-64.zip 
Windows x86-32mid-jre.newyork-06-26-2019__patch8-04-01-2020_04-10-2020_1401.windows.x86-32.zip 
Linux x86-64mid-jre.newyork-06-26-2019__patch8-04-01-2020_04-10-2020_1401.linux.x86-64.zip 
Linux x86-32mid-jre.newyork-06-26-2019__patch8-04-01-2020_04-10-2020_1401.linux.x86-62.zip 
Quebec

A ServiceNow build of OpenJDK 11.0.8 JRE is Supported and Included. (11.0.8-sncmid1)

Linux 32-bit MID Servers, and Linux 64-bit MID Servers with glibc version less than 2.17, cannot use Java 11, and will remain on Java 8.

Note: Quebec includes a fix to preserve the cacerts file, but applies only after you have upgraded, so a Quebec upgrade could lose your cacerst file. That fix is intended to be backported to patches of Orlando and Paris, so to avoid problems due to the cacerts contents being lost, upgrade to a patch of Orlando (specific patch TBC) or Paris Patch 4 or later that already fixes this, to avoid the Java 11 upgrade replacing your cacerts file. For more details see:
PRB1320637 / KB0750004 A MID Server upgrade that includes a new JRE version will overwrite the cacerts file

Rome

32-bit MID Servers are no longer supported on Windows or Linux, so only 64-bit JREs will be included.


Release or Environment

All

Resolution

If you do need to use your own OpenJDK JRE with the MID Server, then follow these instructions:

  1. Using the vendor's own instructions, Install the JRE in the normal way but be sure to install it outside of the MID Server's "agent" install folder. MID Server upgrades can replace anything included within the agent folder, and do regularly delete and replace everything in the bundled JRE's agent/jre/ folder.
  2. Edit the agent/conf/wrapper-override.conf file to tell the MID Server to use the newly installed external JRE. (Use Wordpad and not Notepad on windows, as this is a Unix format file)
  3. Restart the MID Server service.
################################################################################
# External JRE
################################################################################
# Uncomment and edit if an external JRE is preferred. By default,
# the internal JRE distribution is used.
#
# OPTIONAL: The path (relative to agent dir or absolute) to the java bin
wrapper.java.command=C:\ServiceNow_MID_Servers\OpenJDK\8u251\jre\bin\java

Warnings:

  • You are now responsible for keeping the JRE maintained. ServiceNow upgrades will not touch this JRE.
  • If you customise the JRE, perhaps by swapping .jar files within the jre for different versions, then this JRE will no longer be supported by servicenow.

Additional Information

A MID Server downgraded from Quebec to an earlier version will not downgrade the JRE again. This will cause problems due to PRB1419594, which was fixed from Orlando Patch 9 and Paris Patch 4. Downgrades to prior versions will need to turn off performance monitoring of the MID Server, to avoid exceptions from the SIGAR libraries.

https://www.oracle.com/technetwork/java/javase/downloads/jdk8-downloads-2133151.html
https://www.oracle.com/technetwork/java/javase/terms/license/javase-license.html
https://openjdk.java.net/faq/

Article Information

Last Updated:2020-11-30 00:08:17
Published:2020-11-30