How does one add a workstation account to the agsadmin
group on the server? Does this require both machines to be on the same Windows domain?
A colleague cannot connect via ArcCatalog but I don't know how to add his account to the group because the account does not exist on the server. (Oddly I can connect from my machine, but my account is also not a member of the agsadmin
group.)
You can create a workstation account on the server machine for your colleague, and then have your colleague's workstation account on his own machine use the server account's credentials when connecting to the server. I solved a similar problem to this last week and posted the answer here:
How to connect to IIS and SQL Server Express on Windows 7 host from XP Mode
If the user is not in the same domain the easiest way would probably be to add a local user to the server that your colleague can use.As far as I can tell, a user connecting to ArcGIS Server via a Local (LAN) connection must be a domain user. I added my own domain account to the agsuser group which is why it works for me (I did this about three years ago which is why I didn't initially remember how logging into AGS works).If the user is not in your domain, you could use the Internet method to connect (which does require a user name and password).
UPDATE: There is a hacky workaround to this (The Abbott of Monkseato already provided this solution, but I wanted to add the information here as well). Since you have a domain user trying to connect to a local group on a non-domain server, this is more of a network issue than an ArcGIS Server issue.
I asked a question on ServerFault and their response was that you can either:
I think you can do this by creating a local user on your ArcGIS Server box which has the same user name and password as your workstation credentials, add the new user to the Agsadmin or agsuser group. I have never tested this with ESRI but I have managed to do it before with other windows applications.
If that does not work then why not use the web based manager that is installed in the ArcGIS virtual folder. Using this your user should be able to create/stop start and delete services. you will need to create a local user for him to login with.
create any user on the server. add it to agsadmin group. then login as local user of server.
Eg:
Username: {YourServerName}\Username
Password: password