NFS client defaults to a mix of UDP and TCP

[Rick Macklem]

On Mon, 14 Sep 2009, Andriy Gapon wrote:

> on 14/09/2009 15:58 John Baldwin said the following:
>>
>> Yes.  I know of folks would love to have NFS use only TCP, including the
>> initial RPC portmapper requests.  IMO an NFS mount should use TCP for
>> everything and a UDP mount should use UDP for everything by default.
>>
>
> And another fact - it seems that NFS umount unconditionally uses UDP for "something":
>
> /*
> * Report to mountd-server which nfsname
> * has been unmounted.
> */
> if (ai != NULL && !(fflag & MNT_FORCE) && do_rpc) {
>        clp = clnt_create(hostp, MOUNTPROG, MOUNTVERS, "udp");
> ...
>
Yep. This one is somewhat less critical IMO, since this RPC is just
fyi for the mountd on the server and, if it fails for any reason, only
normally affects the output of "showmount" and doesn't break the umount.
(That doesn't mean I don't think it should be fixed, but it can be done
separately from resolving what mount_nfs needs to default to.)

rick