+++ This bug was initially created as a clone of Bug #1129597 +++

Description of problem:
When trying to add a new storage domain with nfsvers=4.1, we get a faliure msg 

vdsm try to run a mount command with both nfsvers=3,nfsvers=4.1 , that is not supported by "mount".

Version-Release number of selected component (if applicable):
oVirt Engine Version: 3.5.0-0.0.master.20140804172041.git23b558e.el6
vdsm-4.16.1-6.gita4a4614.el6.x86_64

How reproducible:
happens all the time 

Steps to Reproduce:
setup: I've used up and running setup with 2 hosts and 2 iSCSI SD's , and 1 VM 

2.through GUI, Storage tab I've added "New Domain"  
3.Default Domain Function / Storage Type - Data/NFS
4.Fill in valid name and Export Path
5.Expand Advanced parameter
6.Check "Override Default Options"
7.Add "nfsvers=4.1" in "Additional mount options"
8.click OK

Actual results:
Operation Failes with a general Error msg "Error while executing action Add Storage Connection: Problem while trying to mount target"

in vdsm.log we see a bad mount call with double param value (nfsvers=3,nfsvers=4.1)

Expected results:
actually we need a definition on what to expect :
- block it on the GUI level, and give a specific msg.
- override of one version param over the other.

Additional info:
/bin/mount -t nfs -o soft,nosharecache,timeo
=600,retrans=6,nfsvers=3,nfsvers=4.1 netapp.qa.la
b.tlv.redhat.com:/vol/vol_gamado_nfs01 /rhev/data
-center/mnt/netapp.qa.lab.tlv.redhat.com:_vol_vol
__gamado__nfs01 (cwd None)
Thread-15::ERROR::2014-08-13 12:44:38,341::storag
eServer::211::Storage.StorageServer.MountConnecti
on::(connect) Mount failed: (32, ';mount.nfs: Pro
tocol not supported\n')
Traceback (most recent call last):
  File "/usr/share/vdsm/storage/storageServer.py"
, line 209, in connect
    self._mount.mount(self.options, self._vfsType)
  File "/usr/share/vdsm/storage/mount.py", line 198, in mount
    return self._runcmd(cmd, timeout)
  File "/usr/share/vdsm/storage/mount.py", line 214, in _runcmd
    raise MountError(rc, ";".join((out, err)))
MountError: (32, ';mount.nfs: Protocol not supported\n')
Thread-15::ERROR::2014-08-13 12:44:38,341::hsm::2427::Storage.HSM::(connectStorageServer) Could not connect to storageServer
Traceback (most recent call last):
  File "/usr/share/vdsm/storage/hsm.py", line 2424, in connectStorageServer
    conObj.connect()
  File "/usr/share/vdsm/storage/storageServer.py"
, line 328, in connect
    return self._mountCon.connect()
  File "/usr/share/vdsm/storage/storageServer.py", line 217, in connect
    raise e
MountError: (32, ';mount.nfs: Protocol not supported\n')

--- Additional comment from Allon Mureinik on 2014-08-13 07:34:31 EDT ---

Sean - what's the required behavior here?

--- Additional comment from Sean Cohen on 2014-08-27 11:38:22 EDT ---

Typically in the industry the default behavior is to attempt mounting first with NFS v4.1, then silently fall back to NFS v3.0 if necessary. 

In our case, when nfsvers=4.1 is selected and the backend does not support then we should notify the user with the relevant error - sometimes the user may specifically require the 4.1 and if we fail back to v3.0 we should also report that..

The question is how do we add the logic for it in vdsm?

Sean

--- Additional comment from Allon Mureinik on 2014-08-27 12:27:41 EDT ---

This is neither urgent nor a blocker for the feature - it's a bad handling for a REALLY bad configuration, which no user will ever perform.

--- Additional comment from Allon Mureinik on 2014-08-28 04:36:33 EDT ---

Talked to Sean - we need to block setting nfsvers (with a CDA) for 3.5, and should look into properly supporting NFS 4.1 for 3.6.

--- Additional comment from Allon Mureinik on 2014-09-04 10:22:35 EDT ---

Tal, when filling in the doctext, please make sure to specify which options have been blocked.

--- Additional comment from Aharon Canan on 2014-09-15 08:31:02 EDT ---

verified, 

nfsvers is blocked.

--- Additional comment from Sandro Bonazzola on 2014-10-17 08:40:49 EDT ---

oVirt 3.5 has been released and should include the fix for this issue.