How to set up network based home folders and authentication to achieve ability to log on from any machine in my home?

Question

For my home network, comprised of one tower/workstation/file-n-print server and several laptops (for each member of the family), all running Ubuntu 9.10 or 9.04, I want to be able to do what the über-cool UNIX/FreeBSD/Linux developers have been doing for almost two decades, namely, from any machine on the network, any user (i.e., family member) is able to log on and have their settings, bookmarks, documents - i.e., her home folder.

The only additional trick I need is that when I travel away from home, I still need to log on and access my stuff on my laptop, and when I plug the laptop back into the network at home, it would need to sync things like updated documents and new bookmarks. A complication would be, however, that I might have done some work from another machine on the network before the laptop was reconnected to the network.

I've done a little research, and I have wondered if something like UnionFS might help with the laptop/network datasync issue. I've looked at NIS vs. LDAP for authentication, but there is too much information out there - it gets overwhelming.

What advice/pointers/links might you offer me to get me started on this endeavour?

Answer 1

LTSP targets thin clients (this could mean diskless, network booting and other functionality you may not be looking for).

Apparently, you are just looking for roaming profiles.

I've just found out about csync. From the homepage:

...csync is a client only bidirectional file synchronizer. You can use csync for different things. The intention is to provide Roaming Home Directories for Linux...

It includes a PAM module to support authentication:

pam_csync is a PAM module to provide roaming home directories for a user session. This module is aimed at environments with central file servers where a user wishes to store his home directory. The Authentication Module verifies the identity of a user and triggers a synchronization with the server on the first login and the last logout.

How it works (from the user page):

csync is a lightweight utility to synchronize files between two directories on a system or between multiple systems. It synchronizes bidirectionally and allows the user to keep two copies of files and directories in sync. csync uses widely adopted protocols, such as smb or sftp, so that there is no need for a server component. It is a user-level program which means you don’t need to be a superuser or administrator. Together with a Pluggable Authentication Module (PAM), the intent is to provide Roaming Home Directories for Linux (see The PAM Module).

Answer 2

You don't need UnionFS. What you are talking about can probably already be done since you are running Ubuntu on all your computers and it's natively supported. When you get to the login screen on Ubuntu there is an option to remotely login to a machine. The term you are looking for is "Terminal Server". Here is some info in respect to Ubuntu.

When you are away from home, and have an internet connection, you can still SSH to your Terminal Server and have access to all your stuff. You can also use a local user on the laptop and later transfer things over to the Terminal Server. I suggest looking through some articles on Google about this. Pretty much you would need to devote one machine as the Terminal Server that manages all the accounts.

I.T. is not really my thing. I might be wrong about some of this. You will get a much better and comprehensive response by posting this question on ServerFault