Have the user1
be in a group, say, group1
and allow group1
to access /home2/users
.
Assuming you have setup user1 be in a group called "group1"
chgrp -R group1 /home2/users
chmod -R 770 /home2/users
If you want the files/dirs created under /home2/users
to be accessible by user1 (regardless who created it) in the future then you will need to set the SGID:
chmod g+s /home2/users
Note that the above command can only be set by the /home2/users
owner.
Can you elaborate more on your objective? Why does user1 needs to access user2's home directory? Will it be bad if user2 can access user1's home directory?