NFS export keytab

INFO: Current debug levels:
  all: 5
  tdb: 5
  printdrivers: 5
  lanman: 5
  smb: 5
  rpc_parse: 5
  rpc_srv: 5
  rpc_cli: 5
  passdb: 5
  sam: 5
  auth: 5
  winbind: 5
  vfs: 5
  idmap: 5
  quota: 5
  acls: 5
  locking: 5
  msdfs: 5
  dmapi: 5
  registry: 5http://pastebin.com/PSuB1b3P
  scavenger: 5
  dns: 5
  ldb: 5
lpcfg_load: refreshing parameters from /etc/samba/smb.conf
params.c:pm_process() - Processing configuration file "/etc/samba/smb.conf"
Processing section "[global]"
Processing section "[netlogon]"
Processing section "[sysvol]"
pm_process() returned Yes
GENSEC backend 'gssapi_spnego' registered
GENSEC backend 'gssapi_krb5' registered
GENSEC backend 'gssapi_krb5_sasl' registered
GENSEC backend 'schannel' registered
GENSEC backend 'spnego' registered
GENSEC backend 'ntlmssp' registered
GENSEC backend 'krb5' registered
GENSEC backend 'fake_gssapi_krb5' registered
added interface lo ip=::1 bcast= netmask=ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff
added interface lo ip=127.0.0.1 bcast=127.255.255.255 netmask=255.0.0.0
added interface pbr0 ip=2001:470:dd5b:74::1 bcast= netmask=ffff:ffff:ffff:ffff::
added interface pbr0 ip=192.168.116.1 bcast=192.168.117.255 netmask=255.255.254.0
added interface lo ip=::1 bcast= netmask=ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff
added interface lo ip=127.0.0.1 bcast=127.255.255.255 netmask=255.0.0.0
added interface pbr0 ip=2001:470:dd5b:74::1 bcast= netmask=ffff:ffff:ffff:ffff::
added interface pbr0 ip=192.168.116.1 bcast=192.168.117.255 netmask=255.255.254.0
schema_fsmo_init: we are master[yes] updates allowed[no]
LDB_lookup_spn_alias: no alias for service nfs applicable
LDB_lookup_spn_alias: no alias for service nfs applicable
LDB_lookup_spn_alias: no alias for service nfs applicable
LDB_lookup_spn_alias: no alias for service nfs applicable
LDB_lookup_spn_alias: no alias for service nfs applicable
ERROR(runtime): uncaught exception - Key table entry not found
  File "/usr/lib/python2.7/dist-packages/samba/netcmd/__init__.py", line 175, in _run
    return self.run(*args, **kwargs)
  File "/usr/lib/python2.7/dist-packages/samba/netcmd/domain.py", line 103, in run
    net.export_keytab(keytab=keytab, principal=principal)