Gandi Docs

$ chown admin:www-data index.html
chown: changing ownership of `index.html': Operation not permitted
[Q1] How should I change the group attribute?

The line is correct but do it logged as root.

I want to keep the simple Gandi AI interface. Activation of root access says,

WARNING! you will no longer have access to the Gandi AI interface if you continue, and you will no longer be able to manage your server via Gandi's website.

$ usermod -g www-data admin
usermod: unable to lock password file
[Q2] How should I join the user admin to the group www-data?

Same answer…

Could there be a fine grain `sudo' operation on user and file management? I don't want root access, I want the GandiAI interface.

[Q3] Should I have a number of accounts as members of www-data group; set files and
directories group readable and writable and, optionally, executable for multiple
users to operate on a common set of files?

I don't understand that one…

Let me try again, I was confusing. Here is a use case:

0/ There is the group www-data. I have two users: userA and userB. I want files and directories to be read and write accessible by userA and userB, I put the users in the www-data group.

1/ With the admin account I want to create the directory /tmp/common with attributes admin(rwx):www-data(rwx):others(rx) – maybe I need a sticky bit set there somewhere, maybe I need www-data(rws)

2/ With the userA account I want to create the file /tmp/common/index.html with attributes userA(rw):www-data(rw):others\(r\)

3/ With the userB account I want to modify the file /tmp/common/index.html

So, it seems, my problem is I want access to chown() usermod() and other related commands without root access to step through the use case.

At the moment I have a file in ~/d_host/www/host.com/htdocs/index.html with attributes admin(rw):admin\(r\):others\(r\) and my userA and userB are unable to modify it.