How to connect an NFS share mount to Unitrends, current share user does not have sufficient permissions KB 1888


You attempt to add an NFS storage device to a Unitrends product, but keep getting errors during the process.


If you still can not get the Unitrends to attach the NFS mount, then the NFS authentication or path is the issue. Use the Linux Command Line Interface from the Unitrends system to prove this. Use any SSH capable Terminal software (we like PuTTY) and connect to your Unitrends system using port 22. The default user is admin and the password is unitrends1.

  1. Find out what path you need to use by executing this command: showmount -e IPADDRESS
A successful output will look like this:
    [root@UEB900BETA ~]# showmount -e
     Export list for
For this example, I created a shared mount on the NAS called Stor. Using the showmount command we see the actual path needs to be /mnt/Stor. The IP address after the mount point is the allowed IP.
  1. If instead, you get this message "rpc mount export: RPC: Procedure unavailable", then check logs in /var/log/messages on the Unitrends appliance to see if is a credentials issue. You can quickly check this by executing this command: grep 'authentication' /var/log/messages
    • If the issue turns out to be authentication, you will need to get this fixed first. Your NFS solution must be able to authenticate using credentials, not just the IP or hostname.
    • The share itself must have read and write permissions enabled. This is different from the user selected permission which also needs read and write permissions.
    • If the NAS will be mounted for the default backup storage or as a Backup Copy Target, the shares on the NAS must be configured  for no_root_squash (aka "No Mapping").
    • NFSv4 is currently not supported.
  2. Depending on your NAS, the value for the Share Name above:
  • might be case sensitive. Type it exactly as listed in the output of the showmount command.
  • might require you to add or drop the / symbol at the beginning (e.g.: mnt/Stor or //mnt/Stor)
User-added image



The following are required for the NAS connection to be successful:

  1. If you are trying to add the NAS as your primary storage device, you must do so as either part of the Setup Wizard or immediately after. Do not add any Protected Assets until you have successfully added the NAS storage to Unitrends, and the Internal shows the size of the storage you have added.
  2. Storage connected using the NFS, CIFS, or iSCSI protocols must not contain spaces in the name.
  3. Create a Top Level Directory for the share mount. Eliminate the need for sub-directory whenever possible. If your NAS has the ability to create provisioned space for the share mount (such as creating a Partition or LUN) use it.
  4. The RecoveryOS requires a username and password to authenticate into a NAS. By default, NAS authentication uses the IP address only. You will need to create a user and assign it to the share.
  5. Do not use use the default ROOT or ADMIN for the NFS share authentication. Security best practice requires you to create a dedicated user and most vendors by default deny share access to these users.


Things to consider if using NFS as the primary storage devices:

  1. Although it is possible to attach external storage directly to the UEB appliance for the purpose of storing and processing backup data (the Internal primary storage), this is not recommended. If you must connect external storage to the UEB directly through network protocols (CIFS, NFS, iSCSI), make sure the solution is listed in KB 3350Supported external storage vendors for use with Unitrends Enterprise Backup appliances.
  2. A NAS connected directly to the UEB for primary storage is the least efficient solution to protect your environment. If you cannot attach the NAS to the Hypervisor via iSCSI (preferred over NFS), and need to directly configure it into the UEB using NFS or CIFS, you need to disable deduplication. This eliminates the issues with hard links and minimizes the I/O hits on the storage device. This is the same requirement for PHD/UVB (they recommended Full/Incremental <dedup off> instead of Virtual Full <dedup on>).
  3. Your Hypervisor may not allow Thick Provisioning on NFS. We strongly recommend that you use iSCSI when possible.

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