* Help: nfs not able to mount large (loopback) directory
@ 2005-06-04 3:19 Dean S. Messing
2005-06-04 4:26 ` Trond Myklebust
2005-06-04 5:28 ` Dan Stromberg
0 siblings, 2 replies; 5+ messages in thread
From: Dean S. Messing @ 2005-06-04 3:19 UTC (permalink / raw)
To: nfs
I have a large .iso image (4GB) on machine B which I have loopback
mounted to directory /mnt/disk.
When I try to nfs mount B:/mnt/disk to machine A I get a "permission
denied" error.
If I replace the 4GB image on machine B with, say, a 700MB .iso image, I have
no problem with the NFS mount on machine A.
I'm running the latest version of MandrivaLinux (2005LE == Mandrake 10.2)
on machine B and MandrakeLinux 10.0 on machine A so the nfs utilites
on machine B (the server) should be nearly current.
In fact:
[root@neuron ~]# rpcinfo -p
program vers proto port
100000 2 tcp 111 portmapper
100000 2 udp 111 portmapper
100003 2 udp 2049 nfs
100003 3 udp 2049 nfs
100003 4 udp 2049 nfs
100003 2 tcp 2049 nfs
100003 3 tcp 2049 nfs
100003 4 tcp 2049 nfs
100021 1 udp 34593 nlockmgr
100021 3 udp 34593 nlockmgr
100021 4 udp 34593 nlockmgr
100021 1 tcp 33635 nlockmgr
100021 3 tcp 33635 nlockmgr
100021 4 tcp 33635 nlockmgr
100005 1 udp 846 mountd
100005 1 tcp 849 mountd
100005 2 udp 846 mountd
100005 2 tcp 849 mountd
100005 3 udp 846 mountd
100005 3 tcp 849 mountd
100024 1 udp 888 status
100024 1 tcp 891 status
Is it the case that nfs (mountd?) can't handle "large" files?
Any help will be much appreciated.
Dean S. Messing
Sr. Scientist
Display Algorithms & Visual Optimization Lab
Sharp Laboratories of America
-------------------------------------------------------
This SF.Net email is sponsored by: NEC IT Guy Games. How far can you shotput
a projector? How fast can you ride your desk chair down the office luge track?
If you want to score the big prize, get to know the little guy.
Play to win an NEC 61" plasma display: http://www.necitguy.com/?r=20
_______________________________________________
NFS maillist - NFS@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/nfs
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: Help: nfs not able to mount large (loopback) directory
2005-06-04 3:19 Help: nfs not able to mount large (loopback) directory Dean S. Messing
@ 2005-06-04 4:26 ` Trond Myklebust
2005-06-05 6:00 ` Dean S. Messing
2005-06-04 5:28 ` Dan Stromberg
1 sibling, 1 reply; 5+ messages in thread
From: Trond Myklebust @ 2005-06-04 4:26 UTC (permalink / raw)
To: Dean S. Messing; +Cc: nfs
fr den 03.06.2005 Klokka 20:19 (-0700) skreiv Dean S. Messing:
>
> I have a large .iso image (4GB) on machine B which I have loopback
> mounted to directory /mnt/disk.
>
> When I try to nfs mount B:/mnt/disk to machine A I get a "permission
> denied" error.
>
> If I replace the 4GB image on machine B with, say, a 700MB .iso image, I have
> no problem with the NFS mount on machine A.
>
> I'm running the latest version of MandrivaLinux (2005LE == Mandrake 10.2)
> on machine B and MandrakeLinux 10.0 on machine A so the nfs utilites
> on machine B (the server) should be nearly current.
> In fact:
>
> [root@neuron ~]# rpcinfo -p
> program vers proto port
> 100000 2 tcp 111 portmapper
> 100000 2 udp 111 portmapper
> 100003 2 udp 2049 nfs
> 100003 3 udp 2049 nfs
> 100003 4 udp 2049 nfs
> 100003 2 tcp 2049 nfs
> 100003 3 tcp 2049 nfs
> 100003 4 tcp 2049 nfs
> 100021 1 udp 34593 nlockmgr
> 100021 3 udp 34593 nlockmgr
> 100021 4 udp 34593 nlockmgr
> 100021 1 tcp 33635 nlockmgr
> 100021 3 tcp 33635 nlockmgr
> 100021 4 tcp 33635 nlockmgr
> 100005 1 udp 846 mountd
> 100005 1 tcp 849 mountd
> 100005 2 udp 846 mountd
> 100005 2 tcp 849 mountd
> 100005 3 udp 846 mountd
> 100005 3 tcp 849 mountd
> 100024 1 udp 888 status
> 100024 1 tcp 891 status
>
>
> Is it the case that nfs (mountd?) can't handle "large" files?
It is true that NFS version 2 cannot handle files > 2GB, but as far as I
gathered you are not exporting the ISO as a single file. Besides, NFSv3
and NFSv4 should be quite capable of dealing with a 4GB file.
This therefore sounds more like it might be some strange interaction
between the loopback driver and nfsd or mountd.
Cheers,
Trond
-------------------------------------------------------
This SF.Net email is sponsored by: NEC IT Guy Games. How far can you shotput
a projector? How fast can you ride your desk chair down the office luge track?
If you want to score the big prize, get to know the little guy.
Play to win an NEC 61" plasma display: http://www.necitguy.com/?r=20
_______________________________________________
NFS maillist - NFS@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/nfs
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: Help: nfs not able to mount large (loopback) directory
2005-06-04 3:19 Help: nfs not able to mount large (loopback) directory Dean S. Messing
2005-06-04 4:26 ` Trond Myklebust
@ 2005-06-04 5:28 ` Dan Stromberg
2005-06-05 6:07 ` Dean S. Messing
1 sibling, 1 reply; 5+ messages in thread
From: Dan Stromberg @ 2005-06-04 5:28 UTC (permalink / raw)
To: Dean S. Messing; +Cc: strombrg, nfs
[-- Attachment #1: Type: text/plain, Size: 2819 bytes --]
I also have found that even small ISO images will lead to problems if
you loopback mount them and NFS export them - EG via NFS v3.
However, if I loopback mount the ISO image, copy it to an ext3 directory
with a tar | tar pipeline, and then NFS export that ext3 directory in
the same way, things work fine.
I'm finding that often userspace->kernel and kernel->userspace work well
in linux, but kernel->kernel interfaces seem to have codepaths that
aren't always tested that much.
On Fri, 2005-06-03 at 20:19 -0700, Dean S. Messing wrote:
>
> I have a large .iso image (4GB) on machine B which I have loopback
> mounted to directory /mnt/disk.
>
> When I try to nfs mount B:/mnt/disk to machine A I get a "permission
> denied" error.
>
> If I replace the 4GB image on machine B with, say, a 700MB .iso image, I have
> no problem with the NFS mount on machine A.
>
> I'm running the latest version of MandrivaLinux (2005LE == Mandrake 10.2)
> on machine B and MandrakeLinux 10.0 on machine A so the nfs utilites
> on machine B (the server) should be nearly current.
> In fact:
>
> [root@neuron ~]# rpcinfo -p
> program vers proto port
> 100000 2 tcp 111 portmapper
> 100000 2 udp 111 portmapper
> 100003 2 udp 2049 nfs
> 100003 3 udp 2049 nfs
> 100003 4 udp 2049 nfs
> 100003 2 tcp 2049 nfs
> 100003 3 tcp 2049 nfs
> 100003 4 tcp 2049 nfs
> 100021 1 udp 34593 nlockmgr
> 100021 3 udp 34593 nlockmgr
> 100021 4 udp 34593 nlockmgr
> 100021 1 tcp 33635 nlockmgr
> 100021 3 tcp 33635 nlockmgr
> 100021 4 tcp 33635 nlockmgr
> 100005 1 udp 846 mountd
> 100005 1 tcp 849 mountd
> 100005 2 udp 846 mountd
> 100005 2 tcp 849 mountd
> 100005 3 udp 846 mountd
> 100005 3 tcp 849 mountd
> 100024 1 udp 888 status
> 100024 1 tcp 891 status
>
>
> Is it the case that nfs (mountd?) can't handle "large" files?
>
> Any help will be much appreciated.
>
> Dean S. Messing
> Sr. Scientist
> Display Algorithms & Visual Optimization Lab
> Sharp Laboratories of America
>
>
> -------------------------------------------------------
> This SF.Net email is sponsored by: NEC IT Guy Games. How far can you shotput
> a projector? How fast can you ride your desk chair down the office luge track?
> If you want to score the big prize, get to know the little guy.
> Play to win an NEC 61" plasma display: http://www.necitguy.com/?r=20
> _______________________________________________
> NFS maillist - NFS@lists.sourceforge.net
> https://lists.sourceforge.net/lists/listinfo/nfs
>
[-- Attachment #2: This is a digitally signed message part --]
[-- Type: application/pgp-signature, Size: 189 bytes --]
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: Help: nfs not able to mount large (loopback) directory
2005-06-04 4:26 ` Trond Myklebust
@ 2005-06-05 6:00 ` Dean S. Messing
0 siblings, 0 replies; 5+ messages in thread
From: Dean S. Messing @ 2005-06-05 6:00 UTC (permalink / raw)
To: trond.myklebust; +Cc: nfs
Trond Myklebust wrote:
: fr den 03.06.2005 Klokka 20:19 (-0700) skreiv Dean S. Messing:
: >
: > I have a large .iso image (4GB) on machine B which I have loopback
: > mounted to directory /mnt/disk.
: >
: > When I try to nfs mount B:/mnt/disk to machine A I get a "permission
: > denied" error.
: >
: > If I replace the 4GB image on machine B with, say, a 700MB .iso image, I have
: > no problem with the NFS mount on machine A.
: >
: > I'm running the latest version of MandrivaLinux (2005LE == Mandrake 10.2)
: > on machine B and MandrakeLinux 10.0 on machine A so the nfs utilites
: > on machine B (the server) should be nearly current.
: > In fact:
: >
: > [root@neuron ~]# rpcinfo -p
: > program vers proto port
: > 100000 2 tcp 111 portmapper
: > 100000 2 udp 111 portmapper
: > 100003 2 udp 2049 nfs
: > 100003 3 udp 2049 nfs
: > 100003 4 udp 2049 nfs
: > 100003 2 tcp 2049 nfs
: > 100003 3 tcp 2049 nfs
: > 100003 4 tcp 2049 nfs
: > 100021 1 udp 34593 nlockmgr
: > 100021 3 udp 34593 nlockmgr
: > 100021 4 udp 34593 nlockmgr
: > 100021 1 tcp 33635 nlockmgr
: > 100021 3 tcp 33635 nlockmgr
: > 100021 4 tcp 33635 nlockmgr
: > 100005 1 udp 846 mountd
: > 100005 1 tcp 849 mountd
: > 100005 2 udp 846 mountd
: > 100005 2 tcp 849 mountd
: > 100005 3 udp 846 mountd
: > 100005 3 tcp 849 mountd
: > 100024 1 udp 888 status
: > 100024 1 tcp 891 status
: >
: >
: > Is it the case that nfs (mountd?) can't handle "large" files?
:
: It is true that NFS version 2 cannot handle files > 2GB, but as far as I
: gathered you are not exporting the ISO as a single file. Besides, NFSv3
: and NFSv4 should be quite capable of dealing with a 4GB file.
:
: This therefore sounds more like it might be some strange interaction
: between the loopback driver and nfsd or mountd.
>From my reading your remarks sound correct. I wonder how I can
fix this problem. Loopback mounting a DVD .iso image and making
it available via NFS has got to be something that is fairly commonly
done.
Dean
-------------------------------------------------------
This SF.Net email is sponsored by: NEC IT Guy Games. How far can you shotput
a projector? How fast can you ride your desk chair down the office luge track?
If you want to score the big prize, get to know the little guy.
Play to win an NEC 61" plasma display: http://www.necitguy.com/?r=20
_______________________________________________
NFS maillist - NFS@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/nfs
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: Help: nfs not able to mount large (loopback) directory
2005-06-04 5:28 ` Dan Stromberg
@ 2005-06-05 6:07 ` Dean S. Messing
0 siblings, 0 replies; 5+ messages in thread
From: Dean S. Messing @ 2005-06-05 6:07 UTC (permalink / raw)
To: nfs
On Fri, 2005-06-03 at 20:19 -0700, Dean S. Messing wrote:
: > I have a large .iso image (4GB) on machine B which I have loopback
: > mounted to directory /mnt/disk.
: > When I try to nfs mount B:/mnt/disk to machine A I get a "permission
: > denied" error.
: > If I replace the 4GB image on machine B with, say, a 700MB .iso image,
: > I have no problem with the NFS mount on machine A.
: > I'm running the latest version of MandrivaLinux (2005LE == Mandrake 10.2)
: > on machine B and MandrakeLinux 10.0 on machine A so the nfs utilites
: > on machine B (the server) should be nearly current.
: > In fact:
: >
: > [root@neuron ~]# rpcinfo -p
: > program vers proto port
: > 100000 2 tcp 111 portmapper
: > 100000 2 udp 111 portmapper
: > 100003 2 udp 2049 nfs
: > 100003 3 udp 2049 nfs
: > 100003 4 udp 2049 nfs
: > 100003 2 tcp 2049 nfs
: > 100003 3 tcp 2049 nfs
: > 100003 4 tcp 2049 nfs
: > 100021 1 udp 34593 nlockmgr
: > 100021 3 udp 34593 nlockmgr
: > 100021 4 udp 34593 nlockmgr
: > 100021 1 tcp 33635 nlockmgr
: > 100021 3 tcp 33635 nlockmgr
: > 100021 4 tcp 33635 nlockmgr
: > 100005 1 udp 846 mountd
: > 100005 1 tcp 849 mountd
: > 100005 2 udp 846 mountd
: > 100005 2 tcp 849 mountd
: > 100005 3 udp 846 mountd
: > 100005 3 tcp 849 mountd
: > 100024 1 udp 888 status
: > 100024 1 tcp 891 status
: >
: > Is it the case that nfs (mountd?) can't handle "large" files?
: > Any help will be much appreciated.
:
: I also have found that even small ISO images will lead to problems if
: you loopback mount them and NFS export them - EG via NFS v3.
:
: However, if I loopback mount the ISO image, copy it to an ext3 directory
: with a tar | tar pipeline, and then NFS export that ext3 directory in
: the same way, things work fine.
:
: I'm finding that often userspace->kernel and kernel->userspace work well
: in linux, but kernel->kernel interfaces seem to have codepaths that
: aren't always tested that much.
According to the version numbers in the output of rpcinfo, I have nfs
v4 available on the server. I have no idea if this makes a
difference, but serving a 700MB CD image via loopback has given me no
problems.
But for some reason I can't serve a DVD .iso image. Of course your
solution of copying the loopback mounted directory into a real
directory is a workaround. But what a waste of space!
It seems to me that serving a DVD .iso via NFS should be a fairly
commonly done thing. Is anyone on this list successfully doing this?
Dean
-------------------------------------------------------
This SF.Net email is sponsored by: NEC IT Guy Games. How far can you shotput
a projector? How fast can you ride your desk chair down the office luge track?
If you want to score the big prize, get to know the little guy.
Play to win an NEC 61" plasma display: http://www.necitguy.com/?r=20
_______________________________________________
NFS maillist - NFS@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/nfs
^ permalink raw reply [flat|nested] 5+ messages in thread
end of thread, other threads:[~2005-06-05 6:07 UTC | newest]
Thread overview: 5+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2005-06-04 3:19 Help: nfs not able to mount large (loopback) directory Dean S. Messing
2005-06-04 4:26 ` Trond Myklebust
2005-06-05 6:00 ` Dean S. Messing
2005-06-04 5:28 ` Dan Stromberg
2005-06-05 6:07 ` Dean S. Messing
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.