We have 4-5 people technicians using a server and as they share a single user account, one person logging in ends the RDP session for someone else.
Which would be a better practice - Using multiple account or allowing multiple sessions for a single admin user?
Windows lets you have multiple accounts (and simultanious accounts) for a reason. Give each person an account. This will allow for better auditing of who did what - especially where something that should not happens happens - for example, if one of your technitians decided to maliciously alter data, its a lot harder to know who did it. Likewise, if you got hacked into, you would have an easier time working out what's the damage.
Having a single admin user is not a good idea. The best thing to do here is to have individual users with the rights to do their jobs. This fixes being able to have parallel sessions too. I wouldn't have shared accounts on my home system let alone a server.
It's bad practice to have 4-5 people sharing the same user account. Fix that first.
From an accountability standpoint you should have individual user accounts instead of a shared account. If someone breaks something or does something that could be a breach of trust, the law etc you could not definitively state which of them had used the account. You might be able to pin an access back to a workstation etc but if that workstation were not secured then the person could just as easily claim that someone else must have used their workstation to execute said activity.
You should also make sure that their passwords are changed regularly, aren't shared between the technicians etc - not much point having individual accounts if people know each others passwords.
At my organisation the default accounts are renamed and changed to a complex password which must be 'checked out' and checked in if they are used (and there has to be a good reason for that (we have audit process that reports on any use of the default administrative accounts via interactive sessions etc.)
EDIT: I believe using multiple accounts would be better. See my original caveat below for why this might not help in practice, given that "one person logging in ends the RDP session for someone else" was given as part of the problem.
I believe you need to be using Terminal Server to allow multiple people to be logged in simultaneously.
