i've used only NFS and as many already found out, it can be or rather i should say, it is very unreliable.
based on the collective experiences of the members on this board, i would really appreciate it if someone can tell me what the next best file sharing method is?
is it DAS? SAN? NAS?
I'd like to know what the most respected, reliable, well tested method is so i can encourage my management to budget for it.
thank you.
btw, i expect to mount whichever method comes out ontop on all types of UNIX hosts (linux, aix, sunos, hpux).
NFS is very reliable - it just wasn't made to replace locally mounted filesystems. NFS is great, for instance, if you export a share with some files, mount it on a remote system, install the files there and then unmount the share again. If you use it to mount 200 GB in 20 filesystems to a remote system and start a database from there you are simply using the wrong tool for the wrong purpose.
Based on your experience, can you tell me what the best method of transportation is? Cars? Bikes? Aeroplanes? Rockets?
I'd say that depends: a car might get you comfortably from home to work and back, but if you want to get to the moon it is probably advisable to use a rocket instead. But if you "only" want to go transcontinental you might be more comfortable using an Airbus A340 instead of a Saturn V, etc..
Each of your mentioned methods have pros and cons and which one is the most fit for your purpose depends heavily upon what purpose that is.
How much data are talking about? Gigabytes? Some TBs? Several hundred TB, up to 1 PB?
How much bandwidth are we talking? Several high-performance real-time-processing OLTP platforms? Cloud computing?
How is this bandwidth used? Many small transactions, like a OLTP? Streams like in a streaming server? Large continuous blocksize reads/writes like a ftp-server? Small blocksize random access like the typical DB/2-LUW?
How much interoperation/data transfer is needed between the different hosts? If the answer is "very much" the answer might be "GPFS", regardless of what storae you use.
What about backup?
What about data replication?
What about snapshots?
I am sure that - off the top of my head - i didn't even ask half of the necessary questions, as others will surely point out. The list above is merely meant to show you how much questions you will first have to ask and answer before you can expect us to give you any competent advice.
I hope this helps.
bakunin