NFS write corruption on 8.0-RELEASE

[Dmitry Marakasov]

* Oliver Fromme (olli at lurza.secnetix.de) wrote:

> This is an excerpt from Solaris' mount_nfs(1M) manpage:
> 
>     File systems that are mounted read-write or that  con-
>     tain  executable  files  should always be mounted with
>     the hard option.  Applications using soft mounted file
>     systems  may incur unexpected I/O errors, file corrup-
>     tion, and unexpected  program  core  dumps.  The  soft
>     option is not recommended.
>
> FreeBSD's manual page doesn't contain such a warning, but
> maybe it should.  (It contains a warning not to use "soft"
> with NFSv4, though, for different reasons.)

Interesting, I'll try disabling it. However now I really wonder why
is such dangerous option available (given it's the cause) at all,
especially without a notice. Silent data corruption is possibly the
worst thing to happen ever.

However, without soft option NFS would be a strange thing to use -
network problems is kinda inevitable thing, and having all processes
locked in a unkillable state (with hard mounts) when it dies is not
fun. Or am I wrong?

> Also note that the "nolockd" option means that processes
> on different clients won't see each other's locks.  That
> means that you will get corruption if they rely on
> locking.

I know - I have no processes that use locks on that filesystems.
Also there's only a single client.

-- 
Dmitry Marakasov   .   55B5 0596 FF1E 8D84 5F56  9510 D35A 80DD F9D2 F77D
amdmi3 at amdmi3.ru  ..:  jabber: amdmi3 at jabber.ru    http://www.amdmi3.ru