Re: NFS client on MacOS X

In article <1187413809.445753.191290@xxxxxxxxxxxxxxxxxxxxxxxxxxxx>,
"borepstein@xxxxxxxxx" <borepstein@xxxxxxxxx> wrote:

Hello all,

I am trying to mount an NFS volume from a Linux-based NFS V2-3-4
server with a Macos X client. I keep failing for some reason. I am
trying to mount it over TCP (UDP is blocked by the firewall). Has
anybody encountered it?

Also, the automount on Macos X seems to only support one moutn at a
time. Any idea why?

Thanks.

Boris.

Just as a general comment/anecdote regarding cross-platform NFS:

I have also run into some real issues getting NFS to work (between my
Mac, as the client, and a Linux box running Knoppmyth as the server).
After much fiddling, I read something [1] that said that NFS actually
uses UID numbers, not usernames, for access once the share is mounted.
So if you are user "joeblow" with UID 501 on one machine, but your
account is "joeblow" with UID 1001 on the other, you'll run into
permissions issues.

What happened to me is that I could mount the share OK (exported home
directory), but couldn't write to it. As it turns out, NFS uses your
actual username to connect to the share but uses the numeric UID when
actually accessing things. Since the UIDs don't match, the server will
refuse to do anything *even though you're logged in as the right user.*

To me this seems like gross stupidity (why would a system ever assume
that your UIDs would be consistent across machines?) but I assume it
probably has its roots in some UNIX history and made sense to someone at
some point [2].

My "solution" was to change my UID on the Linux box to be the same as my
UID on the Mac, a procedure that I don't really recommend trying unless
you *really* need NFS. (There might have been a more elegant solution
but I never found it and I was in a hurry.)

It strikes me that it ought to be possible to specify on the client what
UID you want it to use when communicating with the server (e.g. say
"pretend I'm UID 1001 when talking to this server") but I don't know of
an easy way to do this.

Just something to be on the lookout for.

-Kadin.

[1] <http://www.troubleshooters.com/linux/nfs.htm#_Gotchas>
[2] It probably makes a certain amount of sense if you use NIS to synch
usernames and UIDs across all the machines, but very few people use NIS
anymore.
.

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