A job fails with an error related to NFC (Network File Copy) connectivity. For example:
Error: NFC storage connection is unavailable.
Failed to create NFC download stream.
Failed to create NFC upload stream.
The cause of the majority of NFC errors fall in to 3 primary categories:
*If the account that Veeam Backup & Replication is using to communicate with the VMware Environment has granular permissions set please confirm all permissions are set according to the Granular Permissions Guide.
Due to the natue of NFC as a client server type connection, there is also potential that all things may be correct on the Veeam client side and there exists an issue within the VMware Infrastructure itself.
Note: When investigating this issue it is advisable to reconfigure the job to use a specific proxy. This is done to isolate an issue specific to a single proxy, as well as make it easier to identify which server the logs will found on.
To investigate the potential of a Ports, Permissions, or DNS issue you will need to review the Agent logs.
%programdata%\Veeam\Backup
Agent.<JobName>.Source.<VMName>.log
Agent.<JobName>.Source.<VMName>.log
Agent.<JobName>.Target.<VMName>.log
Creating NFC download stream
nfc| Establishing connection with the host [esx1]. Port: [902]. Failed.
nfc| Sending authd message: [SESSION ID NUMBER]. nfc| Sending authd message: [Name of Host]. nfc| Waiting for the authd reply message...
nfc| Resolving host name (esx1) to IP address... nfc| Resolving host name (esx1) to IP address... Failed.
Further testing can be done using the following PowerShell command, the destination should be the hostname/FQDN/IP shown in the logs for the host.
Test-NetConnection -ComputerName "<destination_host>" -Port 902
If the Proxy is unable to reach port 902, check all applicable Firewalls between the server and the ESXi host.
When a vCenter server or standalone ESXi host is added to the [Backup Infrastructure] section of Veeam Backup & Replication, the user assigns an account to be used. That account should have sufficient privileges to all objects related to the VM being backed up.
The proxy must be able to resolve the hostname or FQDN of the hosts in the Virtual Infrastructure.
Restarting the Management Agents for the ESXi host may be required to correct NFC connection issues.
Other Isolation Ideas:
These are not solutions, they are only meant to help pinpoint a cause.
The proxy being used to process a VM can be identified by opening the “Task” log specific to the VM from inside the folder named after the job in %programdata%\Veeam\Backup. Searching the Task log for the words “starting agent” will allow for the identification of which server performed the task.
Further information can be found in this forum post: http://forums.veeam.com/veeam-backup-replication-f2/failed-to-create-nfc-download-stream-t2991-15.html#p69806
The NFC connection requires the following:
An issue with Port 902 may represent an issue with a firewall on the ESXi host, Veeam Proxy, or the connection between the two.