2004-11-11 14:48:40

by Michael Haverkamp

[permalink] [raw]
Subject: permission denied under load

I have a system running Gentoo Linux with a 2.6.9 kernel that is acting
as an NFS server for several Solaris 7,8,9 systems. Everything appears
to work fine for a while, but at seemingly random times the clients get
"Permission denied" when trying to access a file or directory that they
are normally able to access. This problem may persist for a few
minutes, but then everything returns to normal again. This happens
multiple times a day.

I believe that the problem is more likely to occur under when the server
is under a heavy load. By intentionally stressing the nfs server, I can
usually cause the problem to happen. Also, the problem occurs to all
clients at the same time when it occurs.

Does anyone know what might be causing my problem or know what can be
done about it?


--
Michael Haverkamp


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2004-11-11 14:58:23

by Jan Kasprzak

[permalink] [raw]
Subject: Re: permission denied under load

Michael Haverkamp wrote:
: I have a system running Gentoo Linux with a 2.6.9 kernel that is acting
: as an NFS server for several Solaris 7,8,9 systems. Everything appears
: to work fine for a while, but at seemingly random times the clients get
: "Permission denied" when trying to access a file or directory that they
: are normally able to access. This problem may persist for a few
: minutes, but then everything returns to normal again. This happens
: multiple times a day.
:
See the list archive from the last week or so - I think this
is an "out of privileged ports" problem. Does by any chance the server
(rpc.mountd in particular) complain about unprivileged ports?

-Yenya

--
| Jan "Yenya" Kasprzak <kas at {fi.muni.cz - work | yenya.net - private}> |
| GPG: ID 1024/D3498839 Fingerprint 0D99A7FB206605D7 8B35FCDE05B18A5E |
| http://www.fi.muni.cz/~kas/ Czech Linux Homepage: http://www.linux.cz/ |
> Whatever the Java applications and desktop dances may lead to, Unix will <
> still be pushing the packets around for a quite a while. --Rob Pike <


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2004-11-11 17:25:49

by Michael Haverkamp

[permalink] [raw]
Subject: Re: permission denied under load

There is nothing in the logs about privileged ports or unprivileged ports.

Also, in case I wasn't clear in my first email, the problem happens to
clients that already have the filesystem mounted. Does that mean that
mountd is no longer involved?

Example:

$ mount | grep fmt
/usr/fmt on nfs:/usr/fmt remote/read
only/setuid/bg/timeo=200/proto=udp/xattr/dev=46400fd on Thu Nov 11
05:13:15 2004
$ ls -ld /usr/fmt/coreutils
ls: /usr/fmt/coreutils: Permission denied
$

Wait a while

$ ls -ld /usr/fmt/coreutils
drwxr-xr-x 6 root root 144 May 7 2003 /usr/fmt/coreutils


Jan Kasprzak wrote:
> Michael Haverkamp wrote:
> : I have a system running Gentoo Linux with a 2.6.9 kernel that is acting
> : as an NFS server for several Solaris 7,8,9 systems. Everything appears
> : to work fine for a while, but at seemingly random times the clients get
> : "Permission denied" when trying to access a file or directory that they
> : are normally able to access. This problem may persist for a few
> : minutes, but then everything returns to normal again. This happens
> : multiple times a day.
> :
> See the list archive from the last week or so - I think this
> is an "out of privileged ports" problem. Does by any chance the server
> (rpc.mountd in particular) complain about unprivileged ports?
>
> -Yenya
>

--
Michael Haverkamp


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