Q: I don't get the domain part, for an intranet environnement will I need to come of a name of a domain from my head (of my choice) then create its domain certificate then use it to access the Portal, OR I need to buy that domain (the myorg.net) ?
A: Unless you're starting your organization's domain from scratch, no. Typically, and organization will have a directory server (in Windows terms, that's a domain controller). On a windows machine, you can open a command prompt and enter the command 'IPCONFIG -ALL'. The first set of responses should specify your hostname and your primary DNS suffix. Together, that makes your fully qualified domain name (FQDN) in the format machine.domain.suffix. For instance, I may have a domain called 'randallswidgets.net', and a machine called 'production'. Together, the FQDN will be production.randallswidgets.net. The certificate I obtain will be for *.randallswidgets.net - I'd use the wildcard so that I can apply the cert to multiple machines on the domain. Ask your network administrator if you have an in-house certificate authority from which you can obtain a certificate.
Q: Once I have a domain certificate for myorg.net on the port 443 and then install Portal and ArcGIS web Adaptor I will be able to access the Portal via that link https://wa.myorg.net/arcgis/home without having to mention that domain (myorg.net) while installing Portal or the Adaptor because the certificate on the port 443 is enough to configure that domain with the adaptor, is that true?
A: Kind of. In this case, I'd obtain a certificate with a CN of "*.myorg.net". At the same time, you'd want to set the SAN (Subject Alternative Name) of the cert to just the hostname. You should specify one or more SANs when requesting the cert. Again, your admin can help.
Q: ...for number 3, is the website name is the machine name or what ? I know that the Portal is on https://portal.domain.com:7443/nameOfThePortal/home
so the website name in this case is portal and the domain name is domain.com, isn't it ?
so If I don't have a website name, the default will be my machine name, right ?
A. On Windows machines, when IIS is freshly installed, there is only one website (called Default Website), and it's running on port 80. While the name of the machine *is* used to access the web servers that run on a given machine (a machine may host one or more web servers), unless the default website has been renamed, the identifier will be 'default web site'. You'll need to understand that there are two separate web servers in play: The internal Portal web server (which is not IIS) that runs on port 7443, and the website that runs on the web server that supports the web adaptor (which on Windows is IIS).
Q: Is the basic deployment of ArcGIS Enterprise suitable for a production environnement (6-8 users) ?
A: Yes.
