groupname: member1 member2 member3 member4
group2name: member3 member5
The .htaccess file in your directories can then have a statement along
the lines of:
Require group group2name
We set the actual file names containing groups, along with the
password file to use, in the main Apache configuration.
You can edit these files with a command like:
nano /var/www/conf/private.htgroup
Cheers,