Something has happened with our FAS2040 and the CIFS share. We have SMB v1 enabled, DNS is working, AD has been verified. I have gone through and deleted the AD object and ran through the CIFS setup to recreate the connection, and I have restarted the CIFS service several times.
CIFS domaininfo shows the favored addresses with the IP addresses and FQDNs of our DCs. They all show PDC in the connection.
When a user tried to connect they are present with no folders, but it looks like you are connected. If you try to connect via IP address, authentication does not work regardless of the user you try to use.
My failback was going to be try to access the CIFS share's volume through SFTP and pull the data out, but I do not know how to get connected to it. I can connect to the /vol0/ontap_root/ folder, but not the shared volumes.
I think we found the issue. There was an update released, in our case KB5019964 that broke Kerberos authentication with the NetApp. We are going to limit the connection to one of the DCs that we rolled the update back on and push the department to move the applications off this hardware since it is so past end of life. Very much appreciate the assistance.