What linux lacks most - a decent remote fs

[Les Mikesell]

Tom Horsley wrote:
> 
>> What kind of problems do you see? It can be hard to get firewall 
>> openings right and it depends on uid's matching at the client and server 
>> for file ownership and permissions, but those things either work right 
>> or not at all.  You shouldn't see reliability or performance problems 
>> unless you have hundreds of busy clients.
> 
> What I mostly see is every imaginable problem on different machines
> at different times :-).
> 
> I think the root cause is related to having vast numbers of different
> versions of unix/linux on different machines all of which claim
> to "support" NFS, but which together are highly unreliable (especially
> the ones too old to support tcp connections).

Yes, there were a lot of bad implementations, but usually there were 
enough other things wrong with those system that you'd have replaced or 
updated them by now anyway.

> The worst problem is data corruption on writes, especially writing
> large files across NFS, they will often wind up with large chunks of
> zero bytes in place of the actual data.

Hmmm, this sounds more like a locking issue.  Did you have multiple writers?

> There is one particular machine (in theory running the same dadgum
> version of linux as several others) where some sort of nonsense
> persists in always getting stale NFS filehandle messages any time
> I try to read specific individual files. I always have to unmount
> and remount the filesystem when it gets like this. (Neither system
> was down or not talking at any point, just some fiddling of the
> files in question, replacing them with symlinks, then suddenly the
> stale filehandle messages start).

Open files are cached on the client - renaming stuff on the server while 
a client has it open could cause some odd results.

> The protocols are in theory supposed to support negotiation of the
> correct NFS version when connecting to older machines, but that
> almost never works, we have to manually fiddle fstab entries to
> explicitly give the proper nfsver option or we get things like
> the filesystem is "mounted" but all attempts to access files get
> errors.
> 
> Herding cats has got to have fewer irritations than using NFS :-).

I don't suppose you could cut down on the number of versions that have 
to co-exist...  Or at least get it down to one or a few server types.

-- 
   Les Mikesell
    lesmikesell at gmail.com