Hello Irina, i'm talking to insert a question like this"you are running rhel 5.0 but you have to upgrade at least to 6.0 in order to have supported environment, are you sure tu perform the upgrade?"

I think is safe to pose a question to confirm a setup on unsupported environment (maybe i could start on rhel 5.x and domino 8.53 but i don't want to go on unsupported rhel 5.x and domino 9) 

reading during the installation that you have to upgrade the OS to have a supported environment sound like a joke 

thanks for your time 

Yes Irina, you have understad, my post is talking about the absence of a question about confirm of upgrade.

Folks that have ubuntu, allready know if they are out of support, and also you have wrote, someone could make also upgrade of Domino, and after that upgrade of OS.

But i'm thinking about large environment with many server when admin have some rhel 6 and some 5. Maybe that admin, could made a mistake and upgrade Domino on not supported os, maybe in a server where he don't want/could to upgrade the OS.

Maybe the installer coud to question about upgrade only if start from a supported environment (rhel 5 and dom853) and will go to unsupported (rthel 5 and dom9).

I know is so simple rollback but i think a question in this case  could be more useful than a disclaimer.

Cheers