Re: NFS troubles

[Orion Poplawski <orion@nwra.com>]

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On 04/03/2018 09:44 AM, Orion Poplawski wrote:
> Kernel is 3.10.0-693.21.1.el7.x86_64  I don't have Red Hat support for these
> systems.
> 
> I discovered that I'd been forcing vers=4.0 mounts in order to work around a
> mounting issue.  

And I'm back to seeing the mount issue at boot.  Here's the situation - we're
forcing kerberos on the public network, but allowing sec=sys on some private
networks:

/etc/exports:
/               -ro,async,fsid=0 192.168.1.0/24(sec=sys)
192.168.2.0/24(sec=sys) *.nwra.com(sec=krb5)
/export/home    -rw,async,nohide 192.168.1.0/24(sec=sys)
192.168.2.0/24(sec=sys) *.nwra.com(sec=krb5)

So for a while after boot, attempts to mount with sec=sys fail:

# mount -t nfs4 -s -o
sec=sys,intr,rsize=262144,wsize=262144,noatime,lookupcache=positive,actimeo=1
earthib.cora.nwra.com:/export/home/greg /mnt
mount.nfs4: Operation not permitted

But then later they work:

# mount -t nfs4 -s -o
sec=sys,intr,rsize=262144,wsize=262144,noatime,lookupcache=positive,actimeo=1
earthib.cora.nwra.com:/export/home/greg /mnt
# umount /mnt

This can cycle back and forth.

I've attached a packet capture of some failed mount attempts.  It seems that
even with specifying sec=sys, some kerberos stuff is going on.

It appears to be related to mounting a different sec=krb5 mount over the
public network from the same server.  While that mount is active, the sec=sys
mounts fail.  When it is unmounted, they work.  At least now I think I can
work around this...

-- 
Orion Poplawski
Manager of NWRA Technical Systems          720-772-5637
NWRA, Boulder/CoRA Office             FAX: 303-415-9702
3380 Mitchell Lane                       orion@nwra.com
Boulder, CO 80301                 https://www.nwra.com/

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