[Charlug] AFS

[Jason Edgecombe]

Lawrence Teo wrote:
> Jason Edgecombe wrote:
>> Lawrence Teo wrote:
>>> Hi Jason,
>>>
>>> I've also been hanging around on the list but have yet to be able to 
>>> attend a meeting.. I do recognize your name from the UNCCLUG list. :)
>>>
>>> I have two questions about AFS which I would really appreciate if 
>>> you could answer..
>>>
>>> 1. How is the Arla project related to the OpenAFS project?
>>>
>>> 2. My company's a multi-platform shop.. we run Ubuntu, OpenBSD, 
>>> Macs, Windows XP and Vista. Can OpenAFS be used to set up a file 
>>> server that all these systems can access? If yes, what kind of setup 
>>> is required on the client side?
>>>
>>> Thanks!
>>>
>>> Lawrence
>> Hi Lawrence,
>>
>> I recognize you from the UNCCLUG list as well.
>>
>> 1. AFS is a network filesystem protocol. Both OpenAFS and Arla are 
>> implementations of the AFS protocol. Arla was started because some 
>> folks didn't like the IBM Public license under which OpenAFS is 
>> licensed. I think Arla is under a BSD/MIT-like license. As I recall 
>> Arla has a working client, but I don't know if they have a working 
>> fileserver. Arla, OpenAFS, and IBM/Transarc AFS are interoperable . 
>> OpenAFS the heir apparent of IBM/Trancsarc AFS and so it tends to be 
>> the protocol standard setters as well.
>>
>> 2. Absolutely! In my opinion, OpenAFS' support for different 
>> platforms is second only to NFS and SMB/CIFS. You need an AFS client, 
>> OpenAFS/Arla, installed on each client machine. There is an AFS 
>> client all of the platforms that you mention. Arla has better BSD 
>> support than OpenAFS, but all other platforms have good OpenAFS 
>> clients, BSD servers run well, though. Check on the Openafs-info list 
>> or irc://freenode/openafs about BSD support.
>>
>> AFS is a global filesystem, you can setup a client on your existing 
>> machines to browse other AFS cells/site without needing to set up a 
>> fileserver. Obviously, you will need your own fileserver to host your 
>> own files, but you can try out the client without a fileserver. When 
>> you set up your own cell, you have to add the IP addresses of your 
>> cell/DB server(s) to a config file on each client or add some special 
>> DNS entries. Before you set up a  new cell and fileserver, you will 
>> need to set up Kerberos 5.
>>
>> Since you are on the UNCCLUG list, are you a College of Engineering 
>> student or have a Mosaic account? If so, you can set up an AFS client 
>> and save files into your Mosaic AFS account.
>>
>> I would be happy to answer any other questions that you or anyone 
>> else has about AFS. Also, there are lots of helpful people on the IRC 
>> channel irc://freenode/openafs and the openafs-info mailing list at 
>> https://lists.openafs.org/mailman/listinfo/openafs-info (self-signed 
>> SSL cert)
>
> Jason,
>
> Thank you for your detailed response -- that's very helpful! I *was* a 
> College of IT student who used to have a Mosaic account back in the 
> old days when COIT (now COCI) was using College of Engineering's 
> systems. :) So I have some experience using AFS but not administering it.
>
> The reason why AFS appeals to me over SMB and NFS is because it 
> preserves the UNIX permissions, whereas SMB does not. And AFS seems to 
> be Window-friendly, whereas NFS is less so. (But I may be wrong, I 
> have limited experience with networked filesystems..)
>
You're welcome! My apologies for the poor grammar. Sometimes my brain 
gets ahead of my fingers... ;) I'm glad you have some experience with 
AFS as a user.

AFS does preserve unix permissions, but it only honors the owner bits. 
The group and other bits are ignored and instead, the access is 
controlled by the directory ACL's (access control list). You're right in 
that NFS doesn't seem well-supported under windows. The ironic thing is 
that the NFS standard seems to be adding features to be more like AFS. 
Things like caching support and global namespace support are examples of 
this.

While OpenAFS has very good windows support, there are some areas that 
are lacking and under active development  such as UTF8 support and 
mandatory locking. byte-range locking is emulated as a whole-file lock, 
so multi-user MS Access databases may be problematic. Regular Unix 
advisory locking works as expected.

Be sure to use the latest 1.5.x series for windows and the 1.4.x 
versions for non-windows platforms.

So, have you installed an AFS client yet? Are you ready to set up an AFS 
server?

Sincerely,
Jason