[CentOS] Using CentOS 5 as server; best way to setup NFSv4?

Sat Aug 2 00:33:10 UTC 2008
nate <centos at linuxpowered.net>

Ryan Dunn wrote:

> Thanks for the input.  What would you recommend as a home file server
> instead? Samba?  Also, I just got the RHCE book and am just testing things
> out, so it has been a nice learning experience for me.

Depends on what clients you have, if there is a chance there will
be windows systems on the network at some point it may be good
to at least setup a couple read only shares so you can dump files
to them. Or maybe take a WebDAV approach.

For the linux hosts, NFSv3 is more than enough. NFSv4 really doesn't
seem to have anything that useful in it to make the extra effort
to set it up worth while for most environments.

I personally don't like LDAP(after having used it for many years now).
I do use it at home, though only two of the 6 systems I have are
actually using it(I also use it for mail routing but that is a
legacy thing I setup 7 years ago that I haven't gotten around to
migrating off of). I'm in the slow process of migrating my company's
systems off of LDAP, they are using it for authentication and it's
horribly unreliable and I hate that single point of failure and
the complexity of setting it up and maintaining it. They have a
cron script that restarts the LDAP services every 15 minutes and
they restart nscd on all of the servers every hour. And still even
I get complaints on occasion about not being able to login and I
have to go restart nscd again or at least invalidate the nscd
passwd cache (nscd -i passwd).

My network very rarely has any 3rd party computers connected to it
but something you may want to think about is assigning static IPs to
your own systems, and on the NFS server end setup those IPs as
having read-write to your important shares, and then the rest of
the network can have read-only access.

Then setup a couple public shares where everyone has full read/write
access. Sure someone could spoof an IP or something but if you
have people willing to do that and are on your internal network you
have bigger problems I think.

For my network I just have 2 shares that are wide open to my
local computers. Really only one of them actually has any NFS
volumes mounted though.

> If I were to use LDAP, what would happen if I tried to use the laptop in the
> absence of the server?  Is a local copy stored, ala how my work windows
> network works?

If you use nscd it can cache stuff for a short period of time but
it isn't robust enough to survive a reboot or anything. The system
can automatically fall back to local authentication. If I were
you I suggest just sticking to local authentication.

And I do suggest, if possible to consolidate the userids/group ids
of your systems as another poster suggested if you plan to make
wide spread use of NFS (my environment it's really basic use with
my own account and the root accounts, so uid/gid sync isn't as
important, though it happens to be in sync for the accounts that
I care about). Hopefully it won't be too hard, I haven't checked
much cross distro stuff recently but I am able to use the same
passwd/group/shadow files on RHEL4/RHEL5 and Fedora 8.

But really, stay away from NFSv4 unless you really do understand
what it is for and really need those capabilities. NFSv3 is more
mature, more stable, more compatible, and much easier to setup.
Yes it is less secure but I wouldn't be running NFS period in
an environment where security was critical (or any RPC services
for that matter).

At home I run debian.

nate