NFS Mount Point Failed

[Stephen Morris]

Hi,
     I have the following statement in fstab:

             192.168.1.12:/mnt/HD/HD_a2 /mnt/nfs nfs 
nfsvers=1,x-systemd.automount,defaults 0 0

     When I issue the command 'mount /mnt/nfs' it fails with the 
following messages shown in dmesg, which indicate that the mount seems 
to be trying to proceed via nfs4, why is it doing this when I have the 
option nfsvers=1?

[48439.472418] FS-Cache: Netfs 'nfs' registered for caching
[48439.472732] *** VALIDATE nfs ***
[48439.472741] *** VALIDATE nfs4 ***
[48439.476329] Key type dns_resolver registered
[48439.639981] NFS: Registering the id_resolver key type
[48439.639993] Key type id_resolver registered
[48439.639994] Key type id_legacy registered
[48439.844036] NFS4: Couldn't follow remote path
[48439.852856] NFS4: Couldn't follow remote path
[48439.898650] NFS4: Couldn't follow remote path
[48480.763754] NFS4: Couldn't follow remote path
[48480.774645] NFS4: Couldn't follow remote path

regards,
Steve

[Tom Horsley]

On Tue, 9 Jun 2020 21:54:30 +1000
Stephen Morris wrote:

>  nfsvers=1 
I seriously doubt there is any support for nfs 1 left
in the code (could be wrong).

Depending on random variations every time the nfs
utilities get updates, I've had to sometimes
specify "proto=udp" as well as or instead of
the nfs version in order to speak to antique servers.

[Stephen Morris]

On 9/6/20 10:14 pm, Tom Horsley wrote:
>  On Tue, 9 Jun 2020 21:54:30 +1000
>  Stephen Morris wrote:
>
> > nfsvers=1
>  I seriously doubt there is any support for nfs 1 left
>  in the code (could be wrong).
>
>  Depending on random variations every time the nfs
>  utilities get updates, I've had to sometimes
>  specify "proto=udp" as well as or instead of
>  the nfs version in order to speak to antique servers. 
Thanks Tom, I'll try that
option and see what happens. There is also one 
other thing I don't understand. If I run dolphin, under the Remote 
Section in the left hand panel it shows the entry /mnt/HD/HD_a2:/mnt/nfs 
on 192.168.1.12 which matches the fstab entry, and when I click on that 
entry, dolphin successfully displays the contents of my nas drive. Given 
the manual mount process doesn't work what is dolphin using to actually 
access the drive?

regards,
Steve

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[Tim]

On Tue, 2020-06-09 at 23:01 +1000, Stephen Morris wrote:
>  There is also one other thing I don't understand. If I run
> dolphin,
>  under the Remote Section in the left hand panel it shows the entry
>  /mnt/HD/HD_a2:/mnt/nfs on 192.168.1.12 which matches the fstab entry,
>  and when I click on that entry, dolphin successfully displays the
>  contents of my nas drive. Given the manual mount process doesn't work
>  what is dolphin using to actually access the drive? 
I think if you view /etc/mtab you'll see the parameters being used for
everything that's currently mounted.
 
-- 
 
uname -rsvp
Linux 3.10.0-1127.10.1.el7.x86_64 #1 SMP Wed Jun 3 14:28:03 UTC 2020 x86_64
 
Boilerplate:  All unexpected mail to my mailbox is automatically deleted.
I will only get to see the messages that are posted to the mailing list.

[Roger Heflin]

I used linux in 2.0.X kernels (vintage 1998), and we used version=2,
so I am going to guess there was never a version 1 on linux.

And wikipedia says this interesting bit I did not know:
Sun used version 1 only for in-house experimental purposes.

So I guess that says no one outside of sun used version 1.

On Tue, Jun 9, 2020 at 7:14 AM Tom Horsley <horsley1953(a)gmail.com&gt; wrote:
>
> On Tue, 9 Jun 2020 21:54:30 +1000
> Stephen Morris wrote:
>
> > nfsvers=1
>
> I seriously doubt there is any support for nfs 1 left
> in the code (could be wrong).
>
> Depending on random variations every time the nfs
> utilities get updates, I've had to sometimes
> specify "proto=udp" as well as or instead of
> the nfs version in order to speak to antique servers.
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[Stephen Morris]

On 10/6/20 12:40 am, Roger Heflin wrote:
>  I used linux in 2.0.X kernels (vintage 1998), and we used version=2,
>  so I am going to guess there was never a version 1 on linux.
>
>  And wikipedia says this interesting bit I did not know:
>  Sun used version 1 only for in-house experimental purposes.
>
>  So I guess that says no one outside of sun used version 1. 
Hi Roger, earlier
versions of Fedora (F28) supported version 1 of nfs as 
well as version 4 which they used by default, and I had to set nfsvers=1 
in the mount point in fstab to be able to mount my nas as it only 
supports version 1 of nfs.ff

regards,
Steve

>  On Tue, Jun 9, 2020 at 7:14 AM Tom Horsley <horsley1953(a)gmail.com&gt; wrote:
> > On Tue, 9 Jun 2020 21:54:30 +1000
> > Stephen Morris wrote:
> >
> >> nfsvers=1
> > I seriously doubt there is any support for nfs 1 left
> > in the code (could be wrong).
> >
> > Depending on random variations every time the nfs
> > utilities get updates, I've had to sometimes
> > specify "proto=udp" as well as or instead of
> > the nfs version in order to speak to antique servers.
> > _______________________________________________
> > users mailing list -- users(a)lists.fedoraproject.org
> > To unsubscribe send an email to users-leave(a)lists.fedoraproject.org
> > Fedora Code of Conduct:
> https://docs.fedoraproject.org/en-US/project/code-of-conduct/
> > List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines
> > List Archives:
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[Tom H]

On Tue, Jun 9, 2020 at 2:14 PM Tom Horsley <horsley1953(a)gmail.com&gt; wrote:
>  On Tue, 9 Jun 2020 21:54:30 +1000
>  Stephen Morris wrote:
>
> > nfsvers=1
>
>  I seriously doubt there is any support for nfs 1 left
>  in the code (could be wrong).
>
>  Depending on random variations every time the nfs
>  utilities get updates, I've had to sometimes
>  specify "proto=udp" as well as or instead of
>  the nfs version in order to speak to antique servers. 
nfsd is tcp-only these days. Check out "rpcinfo -s".

[Tom H]

On Tue, Jun 9, 2020 at 1:55 PM Stephen Morris <samorris(a)netspace.net.au&gt; wrote:
>  I have the following statement in fstab:
>
>  192.168.1.12:/mnt/HD/HD_a2 /mnt/nfs nfs
>  nfsvers=1,x-systemd.automount,defaults 0 0
>
>  When I issue the command 'mount /mnt/nfs' it fails with the
>  following messages shown in dmesg, which indicate that the mount
>  seems to be trying to proceed via nfs4, why is it doing this when I
>  have the option nfsvers=1?
>
>  [48439.472418] FS-Cache: Netfs 'nfs' registered for caching
>  [48439.472732] *** VALIDATE nfs ***
>  [48439.472741] *** VALIDATE nfs4 ***
>  [48439.476329] Key type dns_resolver registered
>  [48439.639981] NFS: Registering the id_resolver key type
>  [48439.639993] Key type id_resolver registered
>  [48439.639994] Key type id_legacy registered
>  [48439.844036] NFS4: Couldn't follow remote path
>  [48439.852856] NFS4: Couldn't follow remote path
>  [48439.898650] NFS4: Couldn't follow remote path
>  [48480.763754] NFS4: Couldn't follow remote path
>  [48480.774645] NFS4: Couldn't follow remote path 
nfsv1 has never existed. Use "nfsvers=3" or "nfsvers=4".

[Stephen Morris]

On 10/6/20 7:12 am, Tom H wrote:
>  On Tue, Jun 9, 2020 at 1:55 PM Stephen Morris
> <samorris(a)netspace.net.au&gt; wrote:
> > I have the following statement in fstab:
> >
> > 192.168.1.12:/mnt/HD/HD_a2 /mnt/nfs nfs
> > nfsvers=1,x-systemd.automount,defaults 0 0
> >
> > When I issue the command 'mount /mnt/nfs' it fails with the
> > following messages shown in dmesg, which indicate that the mount
> > seems to be trying to proceed via nfs4, why is it doing this when I
> > have the option nfsvers=1?
> >
> > [48439.472418] FS-Cache: Netfs 'nfs' registered for caching
> > [48439.472732] *** VALIDATE nfs ***
> > [48439.472741] *** VALIDATE nfs4 ***
> > [48439.476329] Key type dns_resolver registered
> > [48439.639981] NFS: Registering the id_resolver key type
> > [48439.639993] Key type id_resolver registered
> > [48439.639994] Key type id_legacy registered
> > [48439.844036] NFS4: Couldn't follow remote path
> > [48439.852856] NFS4: Couldn't follow remote path
> > [48439.898650] NFS4: Couldn't follow remote path
> > [48480.763754] NFS4: Couldn't follow remote path
> > [48480.774645] NFS4: Couldn't follow remote path
>  nfsv1 has never existed. Use "nfsvers=3" or "nfsvers=4". 
Hi
Tom, In another thread to Roger I've mentioned that in F28, and even 
though I didn't specify it, probably F30, Fedora used nfs4 by default 
which would not enable mounting of my nas, I had to specify nfsvers=1 in 
the mount instruction in fstab for the nas to be mounted, which now 
seems to no longer work. Following your suggestion I have tried 
nfsvers=3 and that has enabled the nas to be mounted. Now I have to try 
and figure out the right specification for the cifs mount point to be 
able to be mounted via the Windows share exposed by the nas. Thankyou 
for all your help.

regards,
Steve

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[Roger Heflin]

Sorry, you are confusing the option not causing an issue with it
actaully selecting version=1.

The option may not have caused an issue on f28, but as wikipedia says
and someone else says there never was NFS version 1 (on linux).  It
would seem the behavior when you give it an incorrect mount now causes
it to actually fail, and did not before.

Note I just checked on an old RHEL4 and RHEL5 box (2.6.9/2.6.18
kernel, I believe RHEL4 is based off of Fedora Core 3) and the man
pages says this on both.

   Three different versions of the NFS protocol are supported by the
Linux NFS client: NFS version 2, NFS version 3, and NFS version 4.  To
mount via NFS version 2, use the nfs  file  system
       type  and  specify nfsvers=2.  To mount via NFS version 3, use
the nfs file system type and specify nfsvers=3.  Version 3 is the
default protocol version for the nfs file system type when
       nfsvers= is not specified on the mount command.  To mount via
NFS version 4, use the nfs4 file system type.  The nfsvers= keyword is
not supported for the nfs4 file system type.

So many years prior to F28 there was no mention of 1 existing.

On Tue, Jun 9, 2020 at 6:40 PM Stephen Morris <samorris(a)netspace.net.au&gt; wrote:
>
> On 10/6/20 7:12 am, Tom H wrote:
> > On Tue, Jun 9, 2020 at 1:55 PM Stephen Morris <samorris(a)netspace.net.au&gt;
wrote:
> >> I have the following statement in fstab:
> >>
> >> 192.168.1.12:/mnt/HD/HD_a2 /mnt/nfs nfs
> >> nfsvers=1,x-systemd.automount,defaults 0 0
> >>
> >> When I issue the command 'mount /mnt/nfs' it fails with the
> >> following messages shown in dmesg, which indicate that the mount
> >> seems to be trying to proceed via nfs4, why is it doing this when I
> >> have the option nfsvers=1?
> >>
> >> [48439.472418] FS-Cache: Netfs 'nfs' registered for caching
> >> [48439.472732] *** VALIDATE nfs ***
> >> [48439.472741] *** VALIDATE nfs4 ***
> >> [48439.476329] Key type dns_resolver registered
> >> [48439.639981] NFS: Registering the id_resolver key type
> >> [48439.639993] Key type id_resolver registered
> >> [48439.639994] Key type id_legacy registered
> >> [48439.844036] NFS4: Couldn't follow remote path
> >> [48439.852856] NFS4: Couldn't follow remote path
> >> [48439.898650] NFS4: Couldn't follow remote path
> >> [48480.763754] NFS4: Couldn't follow remote path
> >> [48480.774645] NFS4: Couldn't follow remote path
> > nfsv1 has never existed. Use "nfsvers=3" or "nfsvers=4".
> Hi Tom, In another thread to Roger I've mentioned that in F28, and even
> though I didn't specify it, probably F30, Fedora used nfs4 by default
> which would not enable mounting of my nas, I had to specify nfsvers=1 in
> the mount instruction in fstab for the nas to be mounted, which now
> seems to no longer work. Following your suggestion I have tried
> nfsvers=3 and that has enabled the nas to be mounted. Now I have to try
> and figure out the right specification for the cifs mount point to be
> able to be mounted via the Windows share exposed by the nas. Thankyou
> for all your help.
>
> regards,
> Steve
>
> > _______________________________________________
> > users mailing list -- users(a)lists.fedoraproject.org
> > To unsubscribe send an email to users-leave(a)lists.fedoraproject.org
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[Tom H]

On Wed, Jun 10, 2020 at 1:40 AM Stephen Morris <samorris(a)netspace.net.au&gt; wrote:
>  On 10/6/20 7:12 am, Tom H wrote:
> > On Tue, Jun 9, 2020 at 1:55 PM Stephen Morris <samorris(a)netspace.net.au&gt; wrote:

> >> I have the following statement in fstab:
> >>
> >> 192.168.1.12:/mnt/HD/HD_a2 /mnt/nfs nfs
> >> nfsvers=1,x-systemd.automount,defaults 0 0
> >>
> >> When I issue the command 'mount /mnt/nfs' it fails with the
> >> following messages shown in dmesg, which indicate that the mount
> >> seems to be trying to proceed via nfs4, why is it doing this when I
> >> have the option nfsvers=1?
> >>
> >> [48439.472418] FS-Cache: Netfs 'nfs' registered for caching
> >> [48439.472732] *** VALIDATE nfs ***
> >> [48439.472741] *** VALIDATE nfs4 ***
> >> [48439.476329] Key type dns_resolver registered
> >> [48439.639981] NFS: Registering the id_resolver key type
> >> [48439.639993] Key type id_resolver registered
> >> [48439.639994] Key type id_legacy registered
> >> [48439.844036] NFS4: Couldn't follow remote path
> >> [48439.852856] NFS4: Couldn't follow remote path
> >> [48439.898650] NFS4: Couldn't follow remote path
> >> [48480.763754] NFS4: Couldn't follow remote path
> >> [48480.774645] NFS4: Couldn't follow remote path
> >
> > nfsv1 has never existed. Use "nfsvers=3" or "nfsvers=4".
>
>  In another thread to Roger I've mentioned that in F28, and even
>  though I didn't specify it, probably F30, Fedora used nfs4 by default 
Indeed, nfsv4 has been the default for many releases. So it makes
sense that the mount would fallback to nfsv4 if the requested version
isn't available.


>  which would not enable mounting of my nas, I had to specify
> nfsvers=1
>  in the mount instruction in fstab for the nas to be mounted, which
>  now seems to no longer work. Following your suggestion I have tried
>  nfsvers=3 and that has enabled the nas to be mounted. 
I'm glad that "nfsvers=3" is working. Are you sure that you're not
misremembering "nfsvers=1"?

[Stephen Morris]

On 11/6/20 4:21 am, Tom H wrote:
>  On Wed, Jun 10, 2020 at 1:40 AM Stephen Morris
> <samorris(a)netspace.net.au&gt; wrote:
> > On 10/6/20 7:12 am, Tom H wrote:
> >> On Tue, Jun 9, 2020 at 1:55 PM Stephen Morris <samorris(a)netspace.net.au&gt;
> wrote:
>
> >>> I have the following statement in fstab:
> >>>
> >>> 192.168.1.12:/mnt/HD/HD_a2 /mnt/nfs nfs
> >>> nfsvers=1,x-systemd.automount,defaults 0 0
> >>>
> >>> When I issue the command 'mount /mnt/nfs' it fails with the
> >>> following messages shown in dmesg, which indicate that the mount
> >>> seems to be trying to proceed via nfs4, why is it doing this when I
> >>> have the option nfsvers=1?
> >>>
> >>> [48439.472418] FS-Cache: Netfs 'nfs' registered for caching
> >>> [48439.472732] *** VALIDATE nfs ***
> >>> [48439.472741] *** VALIDATE nfs4 ***
> >>> [48439.476329] Key type dns_resolver registered
> >>> [48439.639981] NFS: Registering the id_resolver key type
> >>> [48439.639993] Key type id_resolver registered
> >>> [48439.639994] Key type id_legacy registered
> >>> [48439.844036] NFS4: Couldn't follow remote path
> >>> [48439.852856] NFS4: Couldn't follow remote path
> >>> [48439.898650] NFS4: Couldn't follow remote path
> >>> [48480.763754] NFS4: Couldn't follow remote path
> >>> [48480.774645] NFS4: Couldn't follow remote path
> >> nfsv1 has never existed. Use "nfsvers=3" or "nfsvers=4".
> > In another thread to Roger I've mentioned that in F28, and even
> > though I didn't specify it, probably F30, Fedora used nfs4 by default
>  Indeed, nfsv4 has been the default for many releases. So it makes
>  sense that the mount would fallback to nfsv4 if the requested version
>  isn't available.
>
>
> > which would not enable mounting of my nas, I had to specify nfsvers=1
> > in the mount instruction in fstab for the nas to be mounted, which
> > now seems to no longer work. Following your suggestion I have tried
> > nfsvers=3 and that has enabled the nas to be mounted.
>  I'm glad that "nfsvers=3" is working. Are you sure that you're not
>  misremembering "nfsvers=1"? 
It is possible I'm not remembering it
correctly. Some time back I had an 
issue where when I specified the mount point in fstab and manually 
issued the mount the mount would fail (I've forgotten the exact syntax 
of the error) and when I raised a query on this list I thought I was 
told to try nfsvers=1, but as you have said I could be mis-remembering 
it. The other thing that I just found that might be interesting is if I 
specify nfsvers=2 I get the message 'protocol not supported'.

regards,
Steve

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[Roger Heflin]

>  It is possible I'm not remembering it correctly. Some time back I
> had an
>  issue where when I specified the mount point in fstab and manually
>  issued the mount the mount would fail (I've forgotten the exact syntax
>  of the error) and when I raised a query on this list I thought I was
>  told to try nfsvers=1, but as you have said I could be mis-remembering
>  it. The other thing that I just found that might be interesting is if I
>  specify nfsvers=2 I get the message 'protocol not supported'.
>
>  regards,
>  Steve
>  

It appears that the kernel defaults to no UDP support be set as
default.  The NFS man page has not yet caught up with the disablement
of UDP. and version=2.   The kernel config does indicate V2 is not set
but does not indicate what the default is but also added this option
CONFIG_NFS_DISABLE_UDP_SUPPORT and if not set but it defaults to "Y",
so no UDP since that is not set.

It also seems portmapper still has UDP and version=2 but the kernel
does not have  either vers=2 or UDP (vers=2 possibly disabled because
no UDP, and I seem to remember vers=3 was the first with tcp and
initial it would not work with >255 clients, I worked with a client
that upgrade from 240 nodes, to 260 nodes and starting going over the
limit).  So a lot of the tools and documentation does not match the
current set of kernel config option being used, or someone did not set
the kernel options to enable UDP.

[Tom H]

On Sat, Jun 13, 2020 at 6:22 AM Stephen Morris <samorris(a)netspace.net.au&gt; wrote:
>  On 11/6/20 4:21 am, Tom H wrote:
> > On Wed, Jun 10, 2020 at 1:40 AM Stephen Morris <samorris(a)netspace.net.au&gt;
> wrote:
> >> On 10/6/20 7:12 am, Tom H wrote:
> >>> On Tue, Jun 9, 2020 at 1:55 PM Stephen Morris
> <samorris(a)netspace.net.au&gt; wrote:
> >>>>
> >>>> I have the following statement in fstab:
> >>>>
> >>>> 192.168.1.12:/mnt/HD/HD_a2 /mnt/nfs nfs
> >>>> nfsvers=1,x-systemd.automount,defaults 0 0
> >>>>
> >>>> When I issue the command 'mount /mnt/nfs' it fails with the
> >>>> following messages shown in dmesg, which indicate that the mount
> >>>> seems to be trying to proceed via nfs4, why is it doing this when I
> >>>> have the option nfsvers=1?
> >>>>
> >>>> [48439.472418] FS-Cache: Netfs 'nfs' registered for caching
> >>>> [48439.472732] *** VALIDATE nfs ***
> >>>> [48439.472741] *** VALIDATE nfs4 ***
> >>>> [48439.476329] Key type dns_resolver registered
> >>>> [48439.639981] NFS: Registering the id_resolver key type
> >>>> [48439.639993] Key type id_resolver registered
> >>>> [48439.639994] Key type id_legacy registered
> >>>> [48439.844036] NFS4: Couldn't follow remote path
> >>>> [48439.852856] NFS4: Couldn't follow remote path
> >>>> [48439.898650] NFS4: Couldn't follow remote path
> >>>> [48480.763754] NFS4: Couldn't follow remote path
> >>>> [48480.774645] NFS4: Couldn't follow remote path
> >>>
> >>> nfsv1 has never existed. Use "nfsvers=3" or "nfsvers=4".
> >>
> >> In another thread to Roger I've mentioned that in F28, and even
> >> though I didn't specify it, probably F30, Fedora used nfs4 by
> >> default
> >
> > Indeed, nfsv4 has been the default for many releases. So it makes
> > sense that the mount would fallback to nfsv4 if the requested
> > version isn't available.
> >
> >> which would not enable mounting of my nas, I had to specify
> >> nfsvers=1 in the mount instruction in fstab for the nas to be
> >> mounted, which now seems to no longer work. Following your
> >> suggestion I have tried nfsvers=3 and that has enabled the nas to
> >> be mounted.
> >
> > I'm glad that "nfsvers=3" is working. Are you sure that you're not
> > misremembering "nfsvers=1"?
>
>  It is possible I'm not remembering it correctly. Some time back I
>  had an issue where when I specified the mount point in fstab and
>  manually issued the mount the mount would fail (I've forgotten the
>  exact syntax of the error) and when I raised a query on this list I
>  thought I was told to try nfsvers=1, but as you have said I could be
>  mis-remembering it. The other thing that I just found that might be
>  interesting is if I specify nfsvers=2 I get the message 'protocol not
>  supported'. 
For "nfsvers=1", I don't know.

For "nfsvers=2", it's either disabled on your server or your client.

Assuming that both are running Fedora 32.

For the server

$ g -A16 nfsd\] /etc/nfs.conf
[nfsd]
# debug=0
# threads=8
# host=
# port=0
# grace-time=90
# lease-time=90
# udp=n
# tcp=y
# vers2=n
# vers3=y
# vers4=y
# vers4.0=y
# vers4.1=y
# vers4.2=y
# rdma=n
# rdma-port=20049
$

For the client

$ g _NFS_ /boot/config-5.6.6-300.fc32.x86_64 | sort
# CONFIG_NFS_DISABLE_UDP_SUPPORT is not set
# CONFIG_NFS_USE_LEGACY_DNS is not set
# CONFIG_NFS_V2 is not set
# CONFIG_NFS_V4_1_MIGRATION is not set
CONFIG_NFS_ACL_SUPPORT=m
CONFIG_NFS_COMMON=y
CONFIG_NFS_DEBUG=y
CONFIG_NFS_FS=m
CONFIG_NFS_FSCACHE=y
CONFIG_NFS_SWAP=y
CONFIG_NFS_USE_KERNEL_DNS=y
CONFIG_NFS_V3=m
CONFIG_NFS_V3_ACL=y
CONFIG_NFS_V4=m
CONFIG_NFS_V4_1=y
CONFIG_NFS_V4_1_IMPLEMENTATION_ID_DOMAIN="kernel.org"
CONFIG_NFS_V4_2=y
CONFIG_NFS_V4_SECURITY_LABEL=y
$

So nfsv2's completely disabled on Fedora.