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Revision as of 16:32, 3 February 2010 by Caiqian (talk | contribs)

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 Package-x-generic-16.pngkrb5-libs first.
    yum -y install krb5-libs
  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
    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
  6. Change /etc/sysconfig/nfs to uncomment or add the following line.
    SECURE_NFS="yes"
  7. Now, restart rpcgssd service.
    service rpcgssd restart
  8. 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?
  9. 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.

  1. If you have not already done so, install Package-x-generic-16.pngkrb5-libs first.
    yum -y install krb5-libs
  2. Configure the NFS server to sync time using NTP to sync the clock for later kerberos communications.
    service ntpd restart
  3. Backup the original krb5.conf, and use the same krb5.conf as the above.
  4. Now, use kadmin to create the server principal - password is "testday" for the pre-configured KDC server.
    kadmin
    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
  5. Change /etc/sysconfig/nfs to uncomment or add the following line.
    SECURE_NFS="yes"
  6. 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
  7. Create test tree structure on the server.
    git clone git://fedorapeople.org/~steved/cthon04
    cd cthon04
    ./runcthon --mkdirs /nfs

Finally, start the test from the client.

  1. Setup the connectathon testsuite from client by root.
    git clone git://fedorapeople.org/~steved/cthon04
    cd cthon04
    make
    mkdir /mnt
    chmod 777 /mnt
  2. Run the testsuite by a non-root user.
    ./runcthon --server <NFS server IP> --serverdir /nfs --onlyv4 --krb5only

Expected Results

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