Summary
I have an SMB share on a domain-joined Synology DS416 NAS. A single computer on our network as a strange issue where the user groupuser
can access the share via hostname \\group_nas\share
with no issue, but when accessing it via IP address \\192.168.11.8\share
, Windows prompts for credentials.
When researching this, I've seen plenty of questions and resources for the reverse case (access via hostname fails but IP is OK) but nothing for my case.
Details:
- I've confirmed that other computers/users do not have this issue.
- The user obviously has access to the share because the DNS name works. I also double-checked permissions to be sure.
- A reboot does not resolve the issue
- Windows updates have been run. I'm on Windows 10 Pro, 1909.
- Entering the credentials when accessing the share via IP requires entering them twice. The first auth never appears to work ("access denied"), while the 2nd always works.
- at first I thought I was just fat-fingering things, but I've been (a) pasting in the password and (b) verifying it by pressing the little "show password" button.
- Mapping a network drive using the DNS name will connect with no issue, but entering the IP addr will still ask for creds
- If connected via IP, the credentials will eventually expire. Not sure how long though, but it seems to be overnight.
- If do the following, then
groupuser
can access the SMB share without needing to enter credentials:- From a fresh boot, sign into Windows as
groupuser
- Switch users to
otheruser
(who also has permisssion to that NAS) - Access the share via IP - no credneital prompt because it's correctly using the Windows creds.
- Sign out of
otheruser
- Sign back in as
groupuser
- From a fresh boot, sign into Windows as
- Rebooting resets everything back to square one.
- From what I've been told, nothing has changed recently on the PC or on the Synology, but of course end users either (a) don't know when things change or (b) don't want to admit they did something.
Has anyone seen this before?
Some other info:
C:\Users\groupuser>net use
New connections will be remembered.
Status Local Remote Network
-------------------------------------------------------------------------------
OK X: \\redacted\UserShares\groupuser
Microsoft Windows Network
OK Y: \\redacted\Admin Microsoft Windows Network
OK Z: \\redacted\Engineering Microsoft Windows Network
The command completed successfully.
C:\Users\groupuser>nslookup 192.168.11.8
Server: localhost
Address: 127.0.0.1
Name: group_nas.contoso.local
Address: 192.168.11.8
C:\Users\groupuser>nslookup group_nas
Server: localhost
Address: 127.0.0.1
Name: group_nas.contoso.local
Address: 192.168.11.8
Why this is important
The operators that run the tools/software on the machine are complaining that they have to log in all the time when they never had to before.
The software on the machine is hard-coded to use the IP address when accessing the share (I'm working with the vendor to make that configurable, but you know how legacy software is...)