First installation or upgrade of Dollar Universe on Linux fails.
On the maintenance.log this error appears:
-----> Please check : That the 32 bits library "libidn" was correctly installed on this system

Else, the following may appear in the installer output:
/tmp/du_as_6.9.XX_linux_26_64/tools/unitestprerq: error while loading shared libraries: libidn.so.11: cannot open shared object file: No such file or directory 
 

Prerequisite not fulfilled.
This is a requirement starting on Dollar Universe 6.1.01
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On Linux, the use of Dollar Universe Manager for SAP Solutions will only be possible if the library
libstdc + +.so.5 is installed. This library must be a 32 bits version.
From Dollar Universe V6.1.01 and later, on UNIX and Linux, the library libidn.so.11 must be installed.
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OS: Linux
 

On Linux systems, you need to install the library libidn.so.11 matching the kit you are using before installing Dollar Universe 6.

You can do so via yum installing one of these packages:

LINUX:
libidn-1.28-4.el7.i686 : Internationalized Domain Name support library

LINUX64;
libidn-1.28-4.el7.x86_64

In order to install the latest version of the package, launch as root the following:
LINUX:
yum install libidn.i686

LINUX64:
yum install libidn

After installing this package successfully, please retry the installation/upgrade of Dollar Universe 6.