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I am currently trying to set up a small network in which my first computer has a NFS share going to three other computers. I have been able to set up this share correctly, however I am having problems in granting full Read/Write permissions to all user accounts across the computers.

At the moment I am not using NIS or any-other account synchronization tool and I am wondering if there is another way, without the need of the mentioned tools.

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Your problem is probably that you have different uids for the same user on the different computers, so michaeld has uid 10401 on computer1, and uid 10575 on computer2. This will confuse NFS, so that it doesn't recognize the two michaeld as being the same user.

You can do what NIS does manually, simply by making sure that all the computers involved have the same users and uid's.

For your environment, the simplest is probably just to make sure that you add users on all four computers with the same UID, but for larger networks you'll have to create a master version of /etc/{passwd,shadow,group,gshadow}, which contain all the users on all the computers, then copy them to all of the computers, of course preserving permissions, and perhaps changing shadow so that users who aren't supposed to be on that computer can't login.

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This is now successfully working for file sharing, however I now need to set up default access rights for newly created files. I have made a change to the default umask, which seems to only be half-functioning at the moment. Any advice you may have on this would be fantastic. Many Thanks! – Michael D Jan 15 '10 at 17:02
umask for nfs is exactly the same as umask for local filesystems, set it in the profile somewhere (eg /etc/profile), and it will be inherited by all child processes. 022 is somewhat standard, though obviously your environment might suggest a different value. – gorilla Jan 15 '10 at 23:23

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