Nfsv4 configuration

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== Base configuration ==
== Base configuration ==
-
This section maybe skiped on most recent distribution. If so, go [[#Exporting_directories|here]]
+
This section may be skipped on most recent distribution. If so, go [[#Exporting_directories|here]]
You should have already built and installed the kernel and user utilities and setup krb5.
You should have already built and installed the kernel and user utilities and setup krb5.
-
The following steps need only be done once. It maybe skiped most recent distribution.
+
The following steps need only be done once. It maybe skipped most recent distribution.
Add the following lines to /etc/fstab to mount the rpc_pipefs and nfsd filesystems automatically:
Add the following lines to /etc/fstab to mount the rpc_pipefs and nfsd filesystems automatically:
Line 34: Line 34:
  rpc.svcgssd  -> this is obsolete as of nfs-utils version 1.0.8-1
  rpc.svcgssd  -> this is obsolete as of nfs-utils version 1.0.8-1
  rpc.nfsd 8
  rpc.nfsd 8
 +
 +
### Feb 2012: I've added some updates on this in the below
On the client, run rpc.gssd and rpc.idmapd:
On the client, run rpc.gssd and rpc.idmapd:
Line 39: Line 41:
  rpc.idmapd
  rpc.idmapd
-
- - -  - - -  - - -
+
== Exporting directories ==
-
Here are some distribution specific guidelines which have been tested on openSUSE and Ubuntu. They attempt to clarify the installation of secure NFS4 on a Linux systems.
+
Export your server directory (in this case, to anyone, using any authentication flavor), by adding the following lines to /etc/exports
-
Source: Steve Sheriff, steve.lcb@gmail.com
+
/export  gss/krb5(rw,fsid=0,insecure,no_subtree_check)
 +
/export  gss/krb5i(rw,fsid=0,insecure,no_subtree_check)
 +
/export  gss/krb5p(rw,fsid=0,insecure,no_subtree_check)
-
Please note that I am not a Linux expert and that I do not usually use English in my day to day life.
+
and then running
-
These notes were written after I faced the task of installing secure NFS4 for a heterogeneous LAN of openSUSE, Ubuntu and Windows clients under a Samba 4 Active Directory PDC. This was tested and reproduced on budget hardware. The largest cost for any single component of the LAN was the licence to activate Windows 7 Professional, needed to join Microsoft clients to AD.
+
exportfs -r
-
I have written this in an attempt to encourage all of us who find ourselves in similar administrative roles, to maintain a centralised deposit of correct information, written in plain English, on modern Linux distributions. I also hope that it will serve to dispel many of the myths I read during the installation and save the countless forays I made into uncharted territory.
+
(Note that if your server is connected to the internet the first line will give everyone in the world read and write access to /export and (with a little work) to anything on the same disk partition as /export! See the exports man page for more information.)
-
Myth: NFS4 must be exported from an fsid=0 pseudo root directory. e.g. I am exporting the /home directory to the clients. The /etc/exports file could be either of these examples.
+
To access this export from a client:
-
e.g. 1. How not to do it
+
Create a mountpoint on your client:
-
/home is bind mounted to chmod'ed 1777 /exports
+
-
/etc/exports
+
-
/export  gss/krb5(rw,fsid=0,insecure,no_subtree_check,crossmnt)
+
-
/export/home gss/krb5(rw,insecure,no_subtree_check)
+
-
/export  gss/krb5i(rw,fsid=0,insecure,no_subtree_check,crossmnt)
+
-
/export/home gss/krb5i(rw,insecure,no_subtree_check)
+
-
/export  gss/krb5(rw,fsid=0,insecure,no_subtree_check,crossmnt)
+
-
/export/home gss/krb5(rw,insecure,no_subtree_check)
+
-
/export  *(rw,fsid=0,insecure,no_subtree_check)
+
-
/export  *(rw,nohide,insecure,no_subtree_check)
+
-
e.g. 2 . Simply use the familiar nfs3 export method.
+
mkdir /mnt/nfs4/
-
/etc/exports
+
-
/home *(rw,sec=none:sys:krb5:krb5i:krb5p,no_subtree_check)
+
-
Choice of 5 flavours for mounting on the client.
+
and mount the server:
-
Please see the comment above: 'The linux implementation allows you. . .'
+
  mount -t nfs4 yourserver:/export /mnt/nfs4/
-
   
+
-
Myth: you must use the nohide option for the bind mount to be visible on the client.
+
-
You can use crossmnt on the pseudoroot or nohide on the bind mount. Or neither and use simply the conventional nfs3 syntex for /etc/exports.
+
-
Myth: NFS4 can only use weak DES cryptography
+
or, to mount with kerberos,
-
e.g. you have been told that NFS4 can only use weak DES cryptography and so you need the line:
+
-
[libdefaults]
+
-
allow_weak_crypto = true
+
-
added to /etc/krb5.conf
+
-
Not needed. Tested using arcfour-hmac-md5 with kernels 3.1.9-1.4-desktop (openSUSE 12.1) and 3.0.0-15-default** (Ubuntu 11.10) **need to check the uname -r output on Ubuntu. Am writing his on  openSUSE
+
-
Myth: NFS4 needs only the nfs/fqdn@REALM principal in it's keytab
+
mount -t nfs4 -o sec=krb5 yourserver:/export /mnt/nfs4/
-
No. It needs the machine principal too. rpc.gssd will not allow you to make a test mount on the server (e.g. to test by mounting to /mnt) unless the machine principal is there along with the nfs principal in the keytab.
+
-
Myth: The client must have a nfs/client.domain principal in its
+
Play around with the mounted filesystem:
-
No. It doesn't need to have one.
+
-
From man rpc.gssd(8)
+
-
Previous versions of rpc.gssd used only "nfs/*" keys found within the keytab. To be more consistent with other implementations, we now look for specific keytab entries. The search order for keytabs to be used for "machine credentials" is now:
+
-
<HOSTNAME>$@<REALM>
+
-
root/<hostname>@<REALM>
+
-
nfs/<hostname>@<REALM>
+
-
host/<hostname>@<REALM>
+
-
root/<anyname>@<REALM>
+
-
nfs/<anyname>@<REALM>
+
-
host/<anyname>@<REALM>
+
-
A real life example. hh3.hh3.site is my server and HH6$@HH3.SITE is the machine principal for the client.
+
  cd /mnt/nfs4/
-
On the client, issue a: mount -t nfs4 hh3:/foo /bar -o sec=krb5
+
echo "Hello World!" >FOO
 +
cat FOO
 +
getfacl FOO
-
Kerberos: ENC-TS Pre-authentication succeeded -- HH6$@HH3.SITE using arcfour-hmac-md5
+
etc.
-
Kerberos: AS-REQ authtime: 2012-02-06T19:44:47 starttime: unset endtime: 2012-02-07T05:44:47 renew till: 2012-02-07T19:44:47
+
-
Kerberos: Client supported enctypes: aes256-cts-hmac-sha1-96, aes128-cts-hmac-sha1-96, des3-cbc-sha1, arcfour-hmac-md5, des-cbc-crc, des-cbc-md5, des-cbc-md4, using arcfour-hmac-md5/arcfour-hmac-md5
+
-
Kerberos: Requested flags: renewable-ok
+
-
Kerberos: TGS-REQ HH6$@HH3.SITE from ipv4:192.168.1.10:45421 for nfs/hh3.hh3.site@HH3.SITE [canonicalize, renewable]
+
-
Kerberos: TGS-REQ authtime: 2012-02-06T19:44:47 starttime: 2012-02-06T19:44:47 endtime: 2012-02-07T05:44:47 renew till: 20
+
-
But remember from above, that the nfs server must be able to identify itself. In this example,
+
To mount a filesystem using krb5, provide the "-osec=krb5" option to mount. To export a filesystem using krb5, export it to the special client named "gss/krb5". Replace "krb5" by "krb5i" or "krb5p" for integrity or for privacy, respectively. The -osec= options should also work for NFSv3 exports and mounts.
-
klist -ke /etc/krb5.keytab
+
 
-
Keytab name: WRFILE:/etc/krb5.keytab
+
Exporting and mounting can be automated using /etc/fstab and /etc/exports; see the man pages fstab(5) and exports(5).
-
KVNO Principal
+
 
-
---- ---------
+
Technical note: NFSv4 no longer has a separate "mount" protocol. Instead of exporting a number of distinct exports, an NFSv4 client sees the NFSv4 server's exports as existing inside a single filesystem, called the nfsv4 "pseudofilesystem".
-
  1 nfs/hh3.hh3.site@HH3.SITE (arcfour-hmac)  
+
 
-
  1 HH3$@hh3.site (arcfour-hmac)
+
The linux implementation allows you to designate a real filesystem as the pseudofilesystem, identifying that export with the fsid=0 option; we no longer recommend this.  Instead, on any recent linux distribution, just list exports in /etc/exports exactly as you would for NFSv2 or NFSv3.
 +
 
 +
== RPC Processes ==
-
rpc processes
 
1. openSUSE after starting the nfs server
1. openSUSE after starting the nfs server
ps aux | grep rpc
ps aux | grep rpc
 +
root      1231  0.0  0.1  2356  764 ?        Ss  08:20  0:00 /sbin/rpcbind
root      1231  0.0  0.1  2356  764 ?        Ss  08:20  0:00 /sbin/rpcbind
 +
root      3737  0.0  0.0      0    0 ?        S<  08:28  0:00 [rpciod]
root      3737  0.0  0.0      0    0 ?        S<  08:28  0:00 [rpciod]
 +
root      5215  0.0  0.2  3684  1208 ?        Ss  09:26  0:00 /usr/sbin/rpc.svcgssd
root      5215  0.0  0.2  3684  1208 ?        Ss  09:26  0:00 /usr/sbin/rpc.svcgssd
 +
root      5223  0.0  0.0  2416  344 ?        Ss  09:26  0:00 /usr/sbin/rpc.idmapd
root      5223  0.0  0.0  2416  344 ?        Ss  09:26  0:00 /usr/sbin/rpc.idmapd
 +
root      5227  0.0  0.1  2976  748 ?        Ss  09:26  0:00 /usr/sbin/rpc.mountd --no-nfs-version 2 --no-nfs-version 3
root      5227  0.0  0.1  2976  748 ?        Ss  09:26  0:00 /usr/sbin/rpc.mountd --no-nfs-version 2 --no-nfs-version 3
(note the lack of gssd)
(note the lack of gssd)
Line 130: Line 106:
ps aux | grep rpc
ps aux | grep rpc
 +
root      1231  0.0  0.1  2356  764 ?        Ss  08:20  0:00 /sbin/rpcbind
root      1231  0.0  0.1  2356  764 ?        Ss  08:20  0:00 /sbin/rpcbind
 +
root      3737  0.0  0.0      0    0 ?        S<  08:28  0:00 [rpciod]
root      3737  0.0  0.0      0    0 ?        S<  08:28  0:00 [rpciod]
 +
root      5215  0.0  0.2  3684  1208 ?        Ss  09:26  0:00 /usr/sbin/rpc.svcgssd
root      5215  0.0  0.2  3684  1208 ?        Ss  09:26  0:00 /usr/sbin/rpc.svcgssd
 +
root      5223  0.0  0.0  2416  344 ?        Ss  09:26  0:00 /usr/sbin/rpc.idmapd
root      5223  0.0  0.0  2416  344 ?        Ss  09:26  0:00 /usr/sbin/rpc.idmapd
 +
root      5227  0.0  0.1  2976  748 ?        Ss  09:26  0:00 /usr/sbin/rpc.mountd --no-nfs-version 2 --no-nfs-version 3
root      5227  0.0  0.1  2976  748 ?        Ss  09:26  0:00 /usr/sbin/rpc.mountd --no-nfs-version 2 --no-nfs-version 3
 +
root      5294  0.0  0.0  3816  428 ?        Ss  09:31  0:00 rpc.gssd
root      5294  0.0  0.0  3816  428 ?        Ss  09:31  0:00 rpc.gssd
-
Installation details
+
== NFS Installation details ==
-
1. openSUSE
+
 
 +
=== openSUSE ===
Packages:
Packages:
zypper in nfs-kernel-server nfs-client nfsidmap limal-nfs-server
zypper in nfs-kernel-server nfs-client nfsidmap limal-nfs-server
Line 144: Line 127:
Configuration (Or use the excellent Yast NFS-Server Module)
Configuration (Or use the excellent Yast NFS-Server Module)
/etc/sysconfig/nfs
/etc/sysconfig/nfs
 +
USE_KERNEL_NFSD_NUMBER="4"
USE_KERNEL_NFSD_NUMBER="4"
 +
MOUNTD_PORT=""
MOUNTD_PORT=""
 +
NFS_SECURITY_GSS="yes"
NFS_SECURITY_GSS="yes"
 +
NFS3_SERVER_SUPPORT="no"
NFS3_SERVER_SUPPORT="no"
 +
NFS4_SUPPORT="yes"
NFS4_SUPPORT="yes"
 +
SM_NOTIFY_OPTIONS=""
SM_NOTIFY_OPTIONS=""
 +
NFS_START_SERVICES="yes"
NFS_START_SERVICES="yes"
 +
STATD_OPTIONS=""
STATD_OPTIONS=""
 +
NFSV4LEASETIME=""
NFSV4LEASETIME=""
 +
RPC_PIPEFS_DIR=""
RPC_PIPEFS_DIR=""
 +
SVCGSSD_OPTIONS=""
SVCGSSD_OPTIONS=""
 +
NFSD_OPTIONS=""
NFSD_OPTIONS=""
-
2. Ubuntu
+
=== Ubuntu ===
Packages:
Packages:
 +
apt-get install nfs-common nfs-kernel-server
apt-get install nfs-common nfs-kernel-server
 +
(you may also need to do a: modprobe nfs before starting the nfs server)
Configuration
Configuration
 +
/etc/default/nfs-common
/etc/default/nfs-common
 +
NEED_STATD=
NEED_STATD=
 +
STATDOPTS=
STATDOPTS=
 +
NEED_IDMAPD=yes
NEED_IDMAPD=yes
 +
NEED_GSSD=yes
NEED_GSSD=yes
 +
/etc/default/nfs-kernel-server
/etc/default/nfs-kernel-server
 +
RPCNFSDCOUNT=8
RPCNFSDCOUNT=8
 +
RPCNFSDPRIORITY=0
RPCNFSDPRIORITY=0
 +
RPCMOUNTDOPTS=--manage-gids
RPCMOUNTDOPTS=--manage-gids
 +
NEED_SVCGSSD=yes
NEED_SVCGSSD=yes
 +
RPCSVCGSSDOPTS=
RPCSVCGSSDOPTS=
 +
RPCNFSDOPTS=
RPCNFSDOPTS=
-
Needed on both client and server on both openSUSE and Ubuntu:
+
 
 +
 
 +
=== Needed on both client and server on both openSUSE and Ubuntu ===
 +
 
/etc/idmapd.conf
/etc/idmapd.conf
 +
[General]
[General]
 +
Verbosity = 0
Verbosity = 0
 +
Pipefs-Directory = /var/lib/nfs/rpc_pipefs
Pipefs-Directory = /var/lib/nfs/rpc_pipefs
-
Domain = hh3.site
+
 
 +
Domain = hh3.site //or whatever your domain is
 +
 
[Mapping]
[Mapping]
 +
Nobody-User = nobody
Nobody-User = nobody
 +
Nobody-Group = nogroup
Nobody-Group = nogroup
-
Debugging
+
== Debugging ==
-
Run rpc.idmapd -fvvv and rpc.gssd -fvvv in separate terminals. They will tell you in no uncertain terms when you've got it wrong.
+
-
rfc
+
Run rpc.idmapd -fvvv and rpc.gssd -fvvv in separate terminals. They will tell you in no uncertain
-
It would be helpful if we could gather together our experiences on NFS4 installation and centralise them here. Particularly helpful would be distribution specific contributions with working examples. My suggestion would be one page per distribution.
+
terms when you've got it wrong. Please see this screenshot:
-
References:
+
http://3.bp.blogspot.com/-PLpbJDP1vCQ/TygMlNU6k8I/AAAAAAAAAGE/lVXsw6iGrS0/s1600/krb5-ubuntu3.png
-
1. This wiki:
+
-
http://wiki.linux-nfs.org/wiki/index.php/Nfsv4_configuration
+
-
2. man rpc.gssd(8)
+
-
http://linux.die.net/man/8/rpc.gssd
+
-
3. A hands on practical using modest hardware. Includes screenshots. openSUSE specific.
+
-
http://linuxcostablanca.blogspot.com/p/samba-4.html
+
-
4. The same as (3) but with Ubuntu specific diffences
+
-
http://linuxcostablanca.blogspot.com/2012/01/samba-4-ubuntu.html
+
-
5. The latest unofficial version of this wiki page. Any new findings, I'll post there.
+
-
http://linuxcostablanca.blogspot.com/2012/02/nfsv4-myths-and-legends.html
+
-
== Exporting directories ==
+
== A Real Life Example ==
-
Export your server directory (in this case, to anyone, using any authentication flavor), by adding the following lines to /etc/exports
+
hh3.hh3.site is the nfs server and  HH6$@HH3.SITE is the machine principal for the client.
 +
On the client, we issue a:
-
/export  gss/krb5(rw,fsid=0,insecure,no_subtree_check)
+
mount -t nfs4 hh3:/foo /bar -o sec=krb5
-
/export  gss/krb5i(rw,fsid=0,insecure,no_subtree_check)
+
-
/export  gss/krb5p(rw,fsid=0,insecure,no_subtree_check)
+
-
and then running
+
Here is the log on the KDC:
-
exportfs -r
+
Kerberos: ENC-TS Pre-authentication succeeded -- HH6$@HH3.SITE using arcfour-hmac-md5
-
(Note that if your server is connected to the internet the first line will give everyone in the world read and write access to /export and (with a little work) to anything on the same disk partition as /export! See the exports man page for more information.)
+
Kerberos: AS-REQ authtime: 2012-02-06T19:44:47 starttime: unset endtime: 2012-02-07T05:44:47 renew till: 2012-02-07T19:44:47
-
To access this export from a client:
+
Kerberos: Client supported enctypes: aes256-cts-hmac-sha1-96, aes128-cts-hmac-sha1-96, des3-cbc-
 +
sha1, arcfour-hmac-md5, des-cbc-crc, des-cbc-md5, des-cbc-md4, using arcfour-hmac-md5/arcfour-hmac-md5
-
Create a mountpoint on your client:
+
Kerberos: Requested flags: renewable-ok
-
mkdir /mnt/nfs4/
+
Kerberos: TGS-REQ HH6$@HH3.SITE from ipv4:192.168.1.10:45421 for nfs/hh3.hh3.site@HH3.SITE [canonicalize, renewable]
-
and mount the server:
+
Kerberos: TGS-REQ authtime: 2012-02-06T19:44:47 starttime: 2012-02-06T19:44:47 endtime: 2012-02-07T05:44:47 renew till: 20
-
mount -t nfs4 yourserver:/export /mnt/nfs4/
+
The nfs server has identified itself, here are the keys in its keytab:
-
or, to mount with kerberos,
+
klist -ke /etc/krb5.keytab
 +
Keytab name: WRFILE:/etc/krb5.keytab
-
  mount -t nfs4 -o sec=krb5 yourserver:/export /mnt/nfs4/
+
KVNO Principal
 +
  1 nfs/hh3.hh3.site@HH3.SITE (arcfour-hmac)  
 +
  1 HH3$@hh3.site (arcfour-hmac)
-
Play around with the mounted filesystem:
+
== Troubleshooting ==
-
cd /mnt/nfs4/
+
http://wiki.linux-nfs.org/wiki/index.php?title=Troubleshooting
-
echo "Hello World!" >FOO
+
-
cat FOO
+
-
getfacl FOO
+
-
etc.
+
== References ==
-
To mount a filesystem using krb5, provide the "-osec=krb5" option to mount. To export a filesystem using krb5, export it to the special client named "gss/krb5". Replace "krb5" by "krb5i" or "krb5p" for integrity or for privacy, respectively. The -osec= options should also work for NFSv3 exports and mounts.
+
1. man rpc.gssd(8)
-
Exporting and mounting can be automated using /etc/fstab and /etc/exports; see the man pages fstab(5) and exports(5).
+
http://linux.die.net/man/8/rpc.gssd
-
Tecnical note: NFSv4 no longer has a separate "mount" protocol. Instead of exporting a number of distinct exports, an NFSv4 client sees the NFSv4 server's exports as existing inside a single filesystem, called the nfsv4 "pseudofilesystem".
+
2. A hands on practical using modest hardware. Includes screenshots. openSUSE specific.
-
The linux implementation allows you to designate a real filesystem as the pseudofilesystem, identifying that export with the fsid=0 option; we no longer recommend this. Instead, on any recent linux distribution, just list exports in /etc/exports exactly as you would for NFSv2 or NFSv3.
+
http://linuxcostablanca.blogspot.com/p/samba-4.html
 +
 
 +
3. The same as (3) but with Ubuntu specific differences
 +
 
 +
http://linuxcostablanca.blogspot.com/2012/01/samba-4-ubuntu.html
 +
 
 +
4. The latest unofficial version of this wiki page. Any new findings, I'll post there.
 +
 
 +
http://linuxcostablanca.blogspot.com/2012/02/nfsv4-myths-and-legends.html

Latest revision as of 16:28, 8 June 2017

from CITI documentation.

Contents

NFSv4 configuration

Base configuration

This section may be skipped on most recent distribution. If so, go here

You should have already built and installed the kernel and user utilities and setup krb5.

The following steps need only be done once. It maybe skipped most recent distribution.

Add the following lines to /etc/fstab to mount the rpc_pipefs and nfsd filesystems automatically: 

rpc_pipefs	/var/lib/nfs/rpc_pipefs	rpc_pipefs	defaults	0	0
nfsd	/proc/fs/nfsd	nfsd	defaults	0	0

and create the mountpoint for rpc_pipefs, and mount both filesystems:

  • mkdir /var/lib/nfs/rpc_pipefs
  • mount rpc_pipefs
  • mount nfsd

Modify the fstab line for filesystem you plan to export on the server to add the "acl" option to the mount options.

Create a directory to export on the server:

  • mkdir /export
  • chmod a+rwxt /export

The following steps need to be performed on every boot; this should really be done by init scripts. The necessary init scripts already exist in recent Fedora distributions. See also debian/nfs-common.init and debian/nfs-kernel-server.init in the patched nfs-utils tarball for example init scripts.

On your server, run rpc.mountd, rpc.svcgssd, rpc.idmapd, and rpc.nfsd: 

rpc.mountd
rpc.idmapd
rpc.svcgssd   -> this is obsolete as of nfs-utils version 1.0.8-1
rpc.nfsd 8
      1. Feb 2012: I've added some updates on this in the below

On the client, run rpc.gssd and rpc.idmapd: 

rpc.gssd -m
rpc.idmapd

Exporting directories

Export your server directory (in this case, to anyone, using any authentication flavor), by adding the following lines to /etc/exports 

/export  gss/krb5(rw,fsid=0,insecure,no_subtree_check)
/export  gss/krb5i(rw,fsid=0,insecure,no_subtree_check)
/export  gss/krb5p(rw,fsid=0,insecure,no_subtree_check)

and then running 

exportfs -r

(Note that if your server is connected to the internet the first line will give everyone in the world read and write access to /export and (with a little work) to anything on the same disk partition as /export! See the exports man page for more information.)

To access this export from a client:

Create a mountpoint on your client: 

mkdir /mnt/nfs4/

and mount the server: 

mount -t nfs4 yourserver:/export /mnt/nfs4/

or, to mount with kerberos, 

mount -t nfs4 -o sec=krb5 yourserver:/export /mnt/nfs4/

Play around with the mounted filesystem: 

cd /mnt/nfs4/
echo "Hello World!" >FOO
cat FOO
getfacl FOO

etc.

To mount a filesystem using krb5, provide the "-osec=krb5" option to mount. To export a filesystem using krb5, export it to the special client named "gss/krb5". Replace "krb5" by "krb5i" or "krb5p" for integrity or for privacy, respectively. The -osec= options should also work for NFSv3 exports and mounts.

Exporting and mounting can be automated using /etc/fstab and /etc/exports; see the man pages fstab(5) and exports(5).

Technical note: NFSv4 no longer has a separate "mount" protocol. Instead of exporting a number of distinct exports, an NFSv4 client sees the NFSv4 server's exports as existing inside a single filesystem, called the nfsv4 "pseudofilesystem".

The linux implementation allows you to designate a real filesystem as the pseudofilesystem, identifying that export with the fsid=0 option; we no longer recommend this. Instead, on any recent linux distribution, just list exports in /etc/exports exactly as you would for NFSv2 or NFSv3.

RPC Processes

1. openSUSE after starting the nfs server

ps aux | grep rpc

root 1231 0.0 0.1 2356 764 ? Ss 08:20 0:00 /sbin/rpcbind

root 3737 0.0 0.0 0 0 ? S< 08:28 0:00 [rpciod]

root 5215 0.0 0.2 3684 1208 ? Ss 09:26 0:00 /usr/sbin/rpc.svcgssd

root 5223 0.0 0.0 2416 344 ? Ss 09:26 0:00 /usr/sbin/rpc.idmapd

root 5227 0.0 0.1 2976 748 ? Ss 09:26 0:00 /usr/sbin/rpc.mountd --no-nfs-version 2 --no-nfs-version 3 (note the lack of gssd)

2. On both openSUSE (after calling rpc.gssd) and Ubuntu with all the necessary processes for successfully exporting the directory with -o sec=krb5<flavour>

ps aux | grep rpc

root 1231 0.0 0.1 2356 764 ? Ss 08:20 0:00 /sbin/rpcbind

root 3737 0.0 0.0 0 0 ? S< 08:28 0:00 [rpciod]

root 5215 0.0 0.2 3684 1208 ? Ss 09:26 0:00 /usr/sbin/rpc.svcgssd

root 5223 0.0 0.0 2416 344 ? Ss 09:26 0:00 /usr/sbin/rpc.idmapd

root 5227 0.0 0.1 2976 748 ? Ss 09:26 0:00 /usr/sbin/rpc.mountd --no-nfs-version 2 --no-nfs-version 3

root 5294 0.0 0.0 3816 428 ? Ss 09:31 0:00 rpc.gssd

NFS Installation details

openSUSE

Packages: zypper in nfs-kernel-server nfs-client nfsidmap limal-nfs-server

Configuration (Or use the excellent Yast NFS-Server Module) /etc/sysconfig/nfs

USE_KERNEL_NFSD_NUMBER="4"

MOUNTD_PORT=""

NFS_SECURITY_GSS="yes"

NFS3_SERVER_SUPPORT="no"

NFS4_SUPPORT="yes"

SM_NOTIFY_OPTIONS=""

NFS_START_SERVICES="yes"

STATD_OPTIONS=""

NFSV4LEASETIME=""

RPC_PIPEFS_DIR=""

SVCGSSD_OPTIONS=""

NFSD_OPTIONS=""

Ubuntu

Packages:

apt-get install nfs-common nfs-kernel-server (you may also need to do a: modprobe nfs before starting the nfs server)

Configuration

/etc/default/nfs-common

NEED_STATD=

STATDOPTS=

NEED_IDMAPD=yes

NEED_GSSD=yes


/etc/default/nfs-kernel-server

RPCNFSDCOUNT=8

RPCNFSDPRIORITY=0

RPCMOUNTDOPTS=--manage-gids

NEED_SVCGSSD=yes

RPCSVCGSSDOPTS=

RPCNFSDOPTS=


Needed on both client and server on both openSUSE and Ubuntu

/etc/idmapd.conf

[General]

Verbosity = 0

Pipefs-Directory = /var/lib/nfs/rpc_pipefs

Domain = hh3.site //or whatever your domain is

[Mapping]

Nobody-User = nobody

Nobody-Group = nogroup

Debugging

Run rpc.idmapd -fvvv and rpc.gssd -fvvv in separate terminals. They will tell you in no uncertain terms when you've got it wrong. Please see this screenshot:

http://3.bp.blogspot.com/-PLpbJDP1vCQ/TygMlNU6k8I/AAAAAAAAAGE/lVXsw6iGrS0/s1600/krb5-ubuntu3.png

A Real Life Example

hh3.hh3.site is the nfs server and HH6$@HH3.SITE is the machine principal for the client. On the client, we issue a:

mount -t nfs4 hh3:/foo /bar -o sec=krb5

Here is the log on the KDC:

Kerberos: ENC-TS Pre-authentication succeeded -- HH6$@HH3.SITE using arcfour-hmac-md5

Kerberos: AS-REQ authtime: 2012-02-06T19:44:47 starttime: unset endtime: 2012-02-07T05:44:47 renew till: 2012-02-07T19:44:47

Kerberos: Client supported enctypes: aes256-cts-hmac-sha1-96, aes128-cts-hmac-sha1-96, des3-cbc- sha1, arcfour-hmac-md5, des-cbc-crc, des-cbc-md5, des-cbc-md4, using arcfour-hmac-md5/arcfour-hmac-md5

Kerberos: Requested flags: renewable-ok

Kerberos: TGS-REQ HH6$@HH3.SITE from ipv4:192.168.1.10:45421 for nfs/hh3.hh3.site@HH3.SITE [canonicalize, renewable]

Kerberos: TGS-REQ authtime: 2012-02-06T19:44:47 starttime: 2012-02-06T19:44:47 endtime: 2012-02-07T05:44:47 renew till: 20

The nfs server has identified itself, here are the keys in its keytab:

klist -ke /etc/krb5.keytab Keytab name: WRFILE:/etc/krb5.keytab

KVNO Principal 

  1 nfs/hh3.hh3.site@HH3.SITE (arcfour-hmac)  
  1 HH3$@hh3.site (arcfour-hmac)

Troubleshooting

http://wiki.linux-nfs.org/wiki/index.php?title=Troubleshooting

References

1. man rpc.gssd(8) 

http://linux.die.net/man/8/rpc.gssd

2. A hands on practical using modest hardware. Includes screenshots. openSUSE specific. 

http://linuxcostablanca.blogspot.com/p/samba-4.html

3. The same as (3) but with Ubuntu specific differences 

http://linuxcostablanca.blogspot.com/2012/01/samba-4-ubuntu.html

4. The latest unofficial version of this wiki page. Any new findings, I'll post there. 

http://linuxcostablanca.blogspot.com/2012/02/nfsv4-myths-and-legends.html
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