From Fedora Project Wiki

Description

This test case is to validates a secure NFSv4 root setup by running the connectathon test suite. This test requires at least 3 systems in the same domain. The first one is a Key Distribution Server (KDC) server, the second one is a NFS server, and the third one is a NFS client.


How to test

  1. First, configure the KDC server. You can use the pre-configured one for the event. If you want to setup your own KDC server, please consult Kerberos_KDC_Quickstart_Guide.
  2. Next, configure the NFS client. If you have not already done so, install krb5-libs and ntp first.
     yum install krb5-libs krb5-workstation ntp
  3. Configure the NFS client to sync time using NTP to sync the clock for later kerberos communications.
     service ntpd restart
  4. Backup the original krb5.conf, and use the the following krb5.conf for the pre-configured KDC server or adjust to use your own.
    [logging]
     default = FILE:/var/log/krb5libs.log
     kdc = FILE:/var/log/krb5kdc.log
     admin_server = FILE:/var/log/kadmind.log
    
    [libdefaults]
     default_realm = FEDORAPROJECT.ORG
     dns_lookup_realm = false
     dns_lookup_kdc = false
     ticket_lifetime = 24h
     renew_lifetime = 7d
     forwardable = yes
    
    [realms]
     FEDORAPROJECT.ORG = {
      kdc = kerberos1.fedoraproject.org:88
      admin_server = kerberos1.fedoraproject.org:749
     }
    
    [domain_realm]
     .fedoraproject.org = FEDORAPROJECT.ORG
     fedoraproject.org = FEDORAPROJECT.ORG
     
  5. Now, use kadmin to create the server principal - password is "testday" for the pre-configured KDC server.
     kadmin root/admin
  6. If it returned a similar error like this, it is likely you will need to fix your system time to be actual.
     kadmin: GSS-API (or Kerberos) error while initializing kadmin interface
  7. Continue...
     kadmin: addprinc -randkey nfs/<NFS client hostname>
     kadmin: ktadd -e des-cbc-crc:normal -k /tmp/keytab nfs/<NFS client hostname>
     kadmin: quit
     cp /etc/krb5.keytab /etc/krb5.keytab.orig
     cp /tmp/keytab /etc/krb5.keytab
  8. Change /etc/sysconfig/nfs to uncomment or add the following line.
     SECURE_NFS="yes"
  9. Now, restart rpcgssd service.
     service rpcgssd restart
  10. If the above failed, check the file /var/log/messages for the presence of a failure similar to the following.
     ERROR: GSS-API: error in gss_acquire_cred(): Unspecified GSS failure. Minor
       code may provide more information - Key table entry not found 
     unable to obtain root (machine) credentials
     do you have a keytab entry for nfs/your.host@YOUR.REALM in /etc/krb5.keytab?
  11. If you find a similar failure in /var/log/messages, it is likely due to incorrect reserve DNS lookup to a loopback address. Look at /etc/hosts, if it has something like this,
     127.0.0.1   localhost localhost.localdomain localhost4 localhost4.localdomain4 <NFS client FQDN>
     ::1         localhost localhost.localdomain localhost6 localhost6.localdomain6 <NFS client FQDN>
    

    Remove the above <NFS client FQDN> from the line, and restart the daemon again. Then, configure the NFS server to find the KDC server.

  12. If you have not already done so, install krb5-libs first.
     yum -y install krb5-libs 
  13. Configure the NFS server to sync time using NTP to sync the clock for later kerberos communications.
     service ntpd restart
  14. Backup the original krb5.conf, and use the same krb5.conf as the above.
  15. Now, use kadmin to create the server principal - password is "testday" for the pre-configured KDC server.
     kadmin root/admin
     kadmin: addprinc -randkey nfs/<NFS server hostname>
     kadmin: ktadd -e des-cbc-crc:normal -k /tmp/keytab nfs/<NFS server hostname>
     kadmin: quit
     cp /etc/krb5.keytab /etc/krb5.keytab.orig
     cp /tmp/keytab /etc/krb5.keytab
  16. Change /etc/sysconfig/nfs to uncomment or add the following line.
     SECURE_NFS="yes"
  17. Next, create an NFS export and restart NFS daemon.
     cp /etc/exports /etc/exports.orig
     echo '/nfs *(sec=sys:krb5:krb5i:krb5p,rw)' >/etc/exports
     mkdir /nfs
     service rpcsvcgssd restart
     service nfs restart
  18. Create test tree structure on the server.
     git clone git://fedorapeople.org/~steved/cthon04
     cd cthon04
     ./runcthon --mkdirs /nfs
     chmod 777 -R /nfs
  19. Make sure the server's firewall allow kerberos communication, or turn of the firewall temporarily.
    iptables -F

    Finally, start the test from the client.

  20. Setup the connectathon testsuite from client by root.
     git clone git://fedorapeople.org/~steved/cthon04
     cd cthon04
     make
     mkdir /mnt
     chmod 777 /mnt
  21. Run the testsuite by root.
     ./runcthon --server <NFS server IP> --serverdir /nfs --onlyv4 --onlykrb5
  22. Save the output from the tests to TESTOUT.log, copy /var/log/messages from both the server and client, and then tar and compress them together with /tmp/nfs*.error if any to upload it to the wiki. Please include a link to the uploaded file in your test day results.
     mkdir log
     scp root@<server hostname>:/var/log/messages messages.server
     cp TESTOUT.log messages.server /var/log/messages /tmp/nfs*.error log/
     tar czvf /tmp/nfs_connectathon-results-<fedora user name>.tgz log/

Expected Results

  1. Step #1 completes without error.
  2. The testsuite finishes without error; no nfs*.error files in /tmp.
  3. Step #3 completes without error.