Gridserver 6.1.1 Hotfix20 is now available and can be downloaded from the support portal under Downloads > Hotfixes > AvailableDownloads > Datasynapse > Gridserver > 6.1.1/ . Here are the release notes:

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Closed Issues in 6.1.1_hotfix20 (This Release)
Build
GS-13364
Added GCC 4.9 compiler support in Linux and LinuxX64.  To use this feature, you
must install the hotfix forcing the JRE update by using the -dsManagerPath and
-updateJRE flags.  See hotfix usage instructions for details.

Documentation
GS-13392
Command line help text has been updated to correctly display default values of
false for optional command line options -updateJRE, -overwriteStartScripts, and
-batch.

Engine
GS-12896
Altered behavior to explicitly capture engine instance ID and provide extra
logging of same.

Java Specific
GS-13347
Java 8 support added for GridServer Manager

GS-13371
Bundled GridServer Manager with Tomcat 8.0.35

Upgrade and Migration
GS-13395
The hotfix installer has been updated to allow all optional parameters
(updateJRE, batch, overwriteStartScripts) to act both as a standalone flag as
well as to optionally accept boolean values such as true or false.

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