I work for a school division (K-12). While I am most interested in what works well on the Mac, Windows and Linux administrators must face the same issue and have analogous solutions.
Most of our computer in a given lab are roughly identical machines. Thus we have labs of new desktops, labs of old desktops, labs of new laptops (with 802.11n) and labs of old laptops (with 802.11g cards).
I'm looking for recommendations for the types of accounts to use. The Mac (and presumably other systems) supports several types of accounts, which I've detailed below.
My specific questions are:
- Have I missed anything in my assessments of the different types of accounts?
- Which sort of accounts would you recommend, for use by largely non-technical students in classes taught by largely non-technical teachers?
- Would you use the same type of accounts on desktops and laptops?
- Do you have tips to mitigate some of the problems? (ex. We use local accounts and allow the students to back up to the network? The teachers enforce a seating chart so that students always use the same machine? We can't think of a better way to teach students to back up files than allow them to lose major assignments?)
- What advice do you offer for a student who uses different computers in different classes? (Possibly a nice new machine in Social Studies and an old laptop in English?)
Update: When describing systems you manage, can you please mention if any users or using laptops (or wireless connections), and if students are working with large files (such as doing audio or visual editing?)
Account Types:
Local Account
Pros:
- Home folder exists on the computer itself; data access could not be faster
- Unaffected by network issues
Cons:
- Requires access to a specific computer
- If the unit fails, data is lost
- Need to create accounts for each user of the computer
Network Account
Pros:
- Data is stored on a server, where it can be properly backed up
- If an end-user computer fails, the data is safe
- Accounts are stored in a directory system; you don't really care where a student logs in
- No time is spent syncing
Cons:
- File access speed is dependent upon network conditions
- Some applications behave poorly or are really slow
- Really should not be used wirelessly
- Back-end services need to be working reliably:
- AFP/NFS/SMB file share must be up and working
- Directory service needs to be working for users to log in
Mobile Accounts
These try to be the best of both worlds. There are two extremes: one where you sync all the data, and one where no data is synced.
Mobile Accounts, No Syncing
Pros:
- Users can lot into a range of machines, and a home folder is created for them
- Data access is fast; it is right on the hard drive
- File servers aren't needed to support it
Cons:
- Initial log-in requires a working network and directory service
- The user needs to use the same computer each time, or they will be unable to access their files
- Home folders accumulate over time and aren't cleared out.
Mobile Accounts, Full Syncing
Pros:
- Users can log into a range of machines, and their home folder is copied off of a file sharing server to the local hard drive (and changes are kept in sync).
- Access is fast; the files are on the hard drive
- Files also live on the server. If a client computer fails, the user can access their files on a different machine.
- This is the ideal setup for a one-to-one laptop deployment.
Cons:
- Syncing conflicts really confuse non-technical users. They don't know how to answer when they are told, "File X differs. Do you want to use the local version of the network version?"
- Syncing a home-folder with lots of data is really slow. So much so that it is best for the user to always use the same computer.
- Home folders accumulate over time and aren't cleared out.
- Syncing requires back-end services to be functioning properly
- Users need to spend time syncing before and after logging in (and syncing continous in the background as they work)
- Especially is students are doing multimedia work, your file server can fill up really quickly. [I gather that quotas have not worked here well in the past.]
Mobile Accounts, Partial Syncing
Pros:
- Less space on the file server is required when you don't sync certain files or folders (like movies, music, and photos)
- Less strain is put on the network
Cons:
- Certain files will only exist on one machine, and live and die with that machine.
- If student expect to use various machines, you really need to make it clear which files will not be synced.
- All problems given in the full syncing, except that the "syncing is really slow" issue is reduced.
Update -- a couple of variations occured to me, and I later saw that they are suggested in Apple's User Management v10.5 document, on p. 142 ("Using Mac OS X Portable Computers with Multiple Users").
Local Accounts, Single Login
Pros:
- Don't have to worry about forgotten passwords!
- Access is fast and doesn't depend on network conditions
- The user account can be created in the master image
Cons:
- It is a free-for all. You can't expect you work to be there the next time you log in (or worse, it may be modified!)
- If it seems that your file is there most of the time, then something important will be lost when you need it
Guest Accounts
Pros:
- You log into a newly created, clean account every time
Cons:
- All files are lost on log-off
- Work has to be saved externally
- Multimedia usage becomes very difficult