[CentOS] Mount/automount fails with krb5-enabled nfs4
James A. Peltier
jpeltier at sfu.ca
Thu Oct 21 13:34:35 EDT 2010
----- Original Message -----
| I have a problem that is driving me crazy. Our nfs server is running
| Solaris. Most clients mount directories from it with no problems, but
| not all. All clients that have problems run CentOS (5.4 and 5.5). I've
| found one or two of each version that fail, but also a couple of each
| version that work.
| The mounting is done for user home directories via autofs but that
| doesn't seem to make any difference, the same problem appears when
| trying to mount manually. Kerberos is used for authentication.
| When I try to mount a directory manually I get this:
| # mount -vvvv -t nfs4 -o sec=krb5 \
| triangulum.ifm.liu.se:/export/users/hans /mnt
| mount: pinging: prog 100003 vers 4 prot tcp port 2049
| mount.nfs4: Permission denied
| I get this in /var/log/messages:
| Oct 15 15:15:12 pc13287 rpc.gssd: rpcsec_gss:
| gss_init_sec_context: (major) Unspecified GSS failure.
| Minor code may provide more information - (minor) Unknown
| code krb5 60
| Oct 15 15:15:12 pc13287 rpc.gssd: WARNING: Failed to create
| krb5 context for user with uid 0 with any credentials cache for
| server triangulum.ifm.liu.se
| The machines that can mount the disk differ slightly in what they log.
| Some log nothing, others this:
| Oct 19 13:26:01 pc14113 rpc.gssd: ERROR: GSS-API: error in
| gss_acquire_cred(): Unspecified GSS failure. Minor code may
| provide more information - Unknown code krb5 195
| Oct 19 13:26:01 pc14113 rpc.gssd: WARNING: Failed to create
| krb5 context for user with uid 121 for server
| Note that there is still an error logged in the first line, but a
| different one. In the second line, the uid if the user changes from 0
| (I'm logged in as root when doing both tests) to 121 (which is the uid
| of the user owning the home directory I'm trying to mount in both
| cases). Perhaps this is a clue, but I don't know what it tries to tell
| I can't find any relevant differences in configuration. I've gone
| through files in /etc on a working and a non-working machine looking
| changes but not finding anything relevant in /etc/sysconfig/nfs,
| /etc/hosts, /etc/idmapd.conf, /etc/krb5.conf, /etc/host.conf,
| /etc/nsswitch.conf, /etc/resolv.conf and others.
| SELinux is not running.
| This is what the keytab looks like on both working and non-working
| # klist -k -e
| Keytab name: FILE:/etc/krb5.keytab
| KVNO Principal
| 3 host/pc13287.ad.ifm.liu.se at IFM.LIU.SE (DES cbc mode with RSA-MD5)
| 3 nfs/pc13287.ad.ifm.liu.se at IFM.LIU.SE (DES cbc mode with RSA-MD5)
| I have an yp master and an yp slave, but there are both working and
| non-working clients connected to both of them.
| There is plenty of space in /tmp and it is writable by all.
| Among the total set of clients there are multiple versions of
| and kernel used, but I can pick a set of one working and one
| client that have the same versions for both (nfs-utils-1.0.9-47.el5_5
| and kernel-2.6.18-194.17.1.el5) so that doesn't appear to be the
| problem. I've tried yum reinstall for the nfs package to no effect.
| doesn't work for the kernel package, but I've compared the md5 sums
| the gss modules between a working and a non-working machine and found
| Obviously, I need to check something else, but what? Please help!
| CentOS mailing list
| CentOS at centos.org
Please post a copy of your /etc/* files listed above so that we might be able to look to make sure everything is correct. You may want to look at ensuring that
is uncommented in /etc/sysconfig/nfs
There might be others missing but we would be able to help best if we know the contents of these files
James A. Peltier
Systems Analyst (FASNet), VIVARIUM Technical Director
Simon Fraser University - Burnaby Campus
Phone : 778-782-6573
Fax : 778-782-3045
E-Mail : jpeltier at sfu.ca
Website : http://www.fas.sfu.ca | http://vivarium.cs.sfu.ca
MSN : subatomic_spam at hotmail.com
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