Cannot install Developer tools 2

Solaris1999

sudo yum groupinstall "Developer Tools"

Loaded plugins: priorities, update-motd, upgrade-helper

Repository testing-devtools-2-centos-latest is listed more than once in the configuration

amzn-main                                                | 2.1 kB     00:00

amzn-updates                                             | 2.3 kB     00:00

http://people.centos.org/tru/devtools-2/latest/x86_64/RPMS/repodata/repomd.xml: [Errno 14] HTTPS Error 404 - Not Found

Trying other mirror.

To address this issue please refer to the below knowledge base article

https://access.redhat.com/articles/1320623

If above article doesn't help to resolve this issue please open a ticket with Red Hat Support.

Warning: group Developer Tools does not exist.

Maybe run: yum groups mark install (see man yum)

Error: No packages in any requested group available to install or update

Any asistance will be much appreciated...