DFS Namespace - The RPC server is unavailable.

Question

A few months ago, we deleted/decommissioned a server name, "DFS-SERVER02" without any issues in our infra. Still, we received notice last week that DFS Namespace "\md.domain.com\data" is not working properly. When the user tries to get that path receives the below error:

Error code: 0x80070043

The network name cannot be found

From the DFS console, I see the below error message:

\md.domain.com\data: The namespace cannot be queried. The RPC server is unavailable.

Well, I ran the following command as my troubleshooting steps:

DFSDiag /TestSites /DFSPath:\md.domain.com\data /Full

Starting TestSites...

Validating the site associations on every domain controller of the following: DFS-SERVER01

Success: The site associated with the following hostname is consistent on all accessible domain controllers: DFS-SERVER01

Validating the static site association by accessing the registry.

Success: The static site-association of the following host name is consistent with the site-association in Active Directory Domain Services (AD DS): DFS-SERVER01

Validating the site associations on every domain controller of the following: DFS-SERVER02

Error: The format of the specified computer name is invalid.

Validating the static site association by accessing the registry.

Error: The format of the specified computer name is invalid.

Error: The RPC server is unavailable.

Finished TestSites.

DFSUtil.exe /pktinfo

Entry: \md.domain.com\data

ShortEntry: \md.domain.com\data

Expires in 0 seconds

UseCount: 1 Type:0x81 ( REFERRAL_SVC DFS )

0:[\DFS-SERVER01\DATA] AccessStatus: 0 ( ACTIVE TARGETSET )

1:[\DFS-SERVER02\DATA] AccessStatus: 0xc00000cc ( TARGETSET )

At this point, it is clear that the server "DFS-SERVER02" is missing, and it was part of the config of the DFSN. As I commented at the start, that server was deleted a few months ago. I reviewed ADSI under "CN=Dfs-Configuration,CN=System,DC=md,DC=domain, DC=com", and I saw some information there, but I cannot see anything related to the membership or ComputerReference.

I appreciate your help on this matter because I do haven't more ideas :)

Answer 1

Hello,

Thank you for your question and for reaching out with your question today.

It seems like the issue is related to the deleted server "DFS-SERVER02" that was part of the DFS Namespace configuration. Even though the server was decommissioned a few months ago, its presence in the DFS Namespace configuration is causing the error you're encountering.

To resolve this issue, you'll need to remove the references to "DFS-SERVER02" from the DFS Namespace configuration. Here's how you can proceed:

1. **ADSIEDIT**: Use the ADSI Edit tool to remove any references to "DFS-SERVER02" from the DFS Namespace configuration. Be cautious while using ADSI Edit, as it directly interacts with Active Directory, and any incorrect changes can cause problems.

2. **DFS Management Console**: Open the DFS Management Console and navigate to the Namespaces. Check if "DFS-SERVER02" is still listed there as a Namespace server. If it is, remove it from the Namespace configuration.

3. **DFS Replication**: If "DFS-SERVER02" was also part of DFS Replication groups, you'll need to remove it from those groups as well.

4. **DFSUtil.exe**: After making any changes, run the "DFSDiag /TestSites" and "DFSUtil.exe /pktinfo" commands again to verify that the references to "DFS-SERVER02" are no longer present and that the DFS Namespace configuration is now consistent.

5. **DFS Namespace Referral Cache**: Clients accessing the DFS Namespace might have cached the referral information, including references to "DFS-SERVER02." You can clear the DFS Namespace referral cache on clients using the following command in the command prompt:

dfsutil /purgeMupCache

6. **Restart DFS Services**: After making changes to the DFS Namespace configuration, consider restarting the DFS Namespace and DFS Replication services to ensure the changes take effect.

Please exercise caution while making changes to the DFS Namespace configuration, and it's always a good idea to have proper backups and verify changes in a test environment before implementing them in a production environment. If you're unsure about any steps or encounter any difficulties, consider seeking assistance from a qualified IT professional or Microsoft Support.

I used AI provided by ChatGPT to formulate part of this response. I have verified that the information is accurate before sharing it with you.

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Best regards.