No pakages in Monitoring group

[root@nethserver ~]# yum grouplist nethserver-nethmonitor
Loaded plugins: changelog, fastestmirror, nethserver_events, presto
Setting up Group Process
Loading mirror speeds from cached hostfile
 * centos-base: mirror.mirohost.net
 * centos-updates: mirror.mirohost.net
 * nethforge: nethserver.de-labrusse.fr
 * nethserver-base: nethserver.de-labrusse.fr
 * nethserver-updates: nethserver.de-labrusse.fr
Available Groups:
   Monitoring and inventorying
Done

[root@nethserver ~]# yum groupinstall "Monitoring and inventorying"
Loaded plugins: changelog, fastestmirror, nethserver_events, presto
Setting up Group Process
Loading mirror speeds from cached hostfile
 * centos-base: mirror.mirohost.net
 * centos-updates: mirror.mirohost.net
 * nethforge: nethserver.de-labrusse.fr
 * nethserver-base: nethserver.de-labrusse.fr
 * nethserver-updates: nethserver.de-labrusse.fr
Warning: Group nethserver-nethmonitor does not have any packages.
No packages in any requested group available to install or update