Duplicate spn issues. Entry 5 is processed.

Duplicate spn issues This is due to the fact that duplicate SPNs cannot exist in the same forest. Include my email address so I can be contacted. DOM HOST/ADFS01 . You cannot remove The SPN host/ADFS01. In this screenshot, the UI has the following tabs: System: Displays the user information and machine information. Commented Aug 30, 2022 at 11:00. Optional: If you want to use the tool to fix any SPN issues that are identified by the tool, the domain account should have the Validated write to service principle name permission. I ran the wizard again and I am getting this message. More information: Duplicate SPNs aren't very common but can happen in any Active Directory as there's no built-in way that tracks and prevent duplicate SPN's. How should I do that? I am now on commit a649c62 (09 Duplicate SPN found - Troubleshooting Duplicate SPNs Symptoms. We will now cover what things look like when the Service Principal Name is NOT added to the correct account. On the file server, check what SPNs are registered in the local keytab file. However, my command output for PS C:\\Windows\\system32> setspn -X Checking domain DC=ST,DC=RAY Processing entry 1 found 0 group of duplicate SPNs. Now the tricky partthis server has not existed for many years, so many that nobody even remembers what it was. Hot Network Questions Search code, repositories, users, issues, pull requests Search Clear. notspicehead (NotSpicehead) August 20, 2019, 5:17pm 3. General Syntax of SPNs is service class/fqdn@REALM , There are also User Principal Names which identify users, in form of user@Domain Kerberos requires that the SPN be unique and there should be a single SPN The DC giving the issue holds no roles except for fail-over DHCP & DNS But I’m not sure if making a new DC & demoting the problem one is going to give me the same grief, or if trying to demote the troubled DC with duplicate SPNs is going to cause another domino to fall somewhere else. msc to view the 'serviceprincipalname' attribute Duplicate SPN found, aborting operation! I further read a bunch of articles that recommended deleting the SPN and recreating it using the "setspn -D" command but, I was kind of hoping to get some feedback before continuing. Since there is nothing to When a domain controller detects duplicate service principal names (SPN), authentication may fall back from Kerberos to the vulnerable authentication protocol NTLM. com is registered on these accounts: CN=EXCHCAS2,OU=Production, OU=Servers,DC=domain,DC=com CN=EXCHCAS1,OU=Production, OU=Servers,DC=domain,DC=com On the domain control I Duplicate SPNs - Which one do I delete? Windows. local setspn -D MSSQLSvc/SQL01:1433 SQL01 Nevertheless, my DC spits out the event that there is still this duplicate SPN with nice regularity. Please ensure that the target SPN is registered on, and only registered on, the account used by the server. The SquaredUp DS Kerberos script Debug-SquaredUpKerberos. I did find this: But I am not comfortable installing a hotfix. Duplicate SPN Issue. SETSPN -f -x This is known as a duplicate SPN issue. if i check setspn -L “myscomserver”, there are the following two entries: – MSOMSdkSvc/”myscomserver. I dug through the event viewer and found the event id11. Below is a SS showing the The DC giving the issue holds no roles except for fail-over DHCP & DNS But I’m not sure if making a new DC & demoting the problem one is going to give me the same grief, or if trying to demote the troubled DC with duplicate SPNs is going to cause another domino to fall somewhere else. There may be duplicate SPNs or an SPN that's registered under an account other than the AD FS service account. You can use this tool to verify that SQL Server SPNs are configured as per Register a Service Principal Name for Kerberos TL;DR: how should I duplicate an SPN? I have a big IVs and I want the duplicated SPNs to take different subsets of indicators from this big IVs. Overview. This ranged from DHDiag (an internal CSS tool that uses LDIFDE) to queryspn. Since then 3. 1. 9: 336: November 30, 2017 Home ; Categories Duplicate SPN: What is it really? 1 Spice up. I have a duplicate SPN that even when I unreg it, it keeps coming back. Visit Stack Exchange Check you don't have duplicate and incorrect SPNs registered against the user account this will also cause issues. But that returns positively that there are no duplicate SPNs. Usually this is when the Administrator has used the SetSPN on different accounts in an effort to get Kerberos Authentication to work. To download and run the Kerberos script see Collecting diagnostic information. Troubleshooting Kerberos SquaredUp DS Kerberos script. If you want to configure your SQL Server to run with a service account, you must first remove the SPN's that are registered on the computer account and then register the SPN's to the service account. txt contains That could cause problems, if the app pool account doesn't have the right permissions to things. Try flushing the DNS cache on the virtual machine using the ipconfig /flushdns command. Duplicate SPNs can cause authentication issues. I believe you have done all the right things by adding SPN's for service account but there is one more step in IIS that you need to take to ensure that the application pool credentials are actually being used. . Here is the steps. local' and it shows that I have possible missing SPNs. Event ID 11 — Service Principal Name Configuration | Microsoft Learn How to check for duplicate SPN's on computer objects in the domain. However, if the account on the SPN is not the RunAs user, then the existing SPN must be deleted so the SPN can be re-created on the correct account. Status - Duplicate SPN. Since the SPN is always registered via the shortname, the intent is to run the script prior to naming a new machine to confirm that the name will be valid in Describe the bug Duplicate SPN section only works if report is runned on a Domain Controller server To Reproduce Steps to reproduce the behavior: Run the report on a device other than a DC The repo Check what account the duplicate SPN is registered under. This issue can occur when the UPN of a Issue 2: Intra-forest migration If you perform an intra-forest user migration that has service principal name (SPN) or user principal name (UPN) defined or intra-forest computer migration, the migration fails because the account still exists in the global catalog as the object is introduced in the target domain that has these attributes populated. Identifying and removing duplicate SPNs is essential to ensure the smooth operation of the SQL Server and First you want to list the SPNs to identify the duplicate SPN: setspn -L <server> Then to remove the duplicate SPN: setspn -d service/name hostname Service/name is the SPN that is to be removed and hostname is the actual host name of the computer. Group Policy Update Issues: Note: All of your Kerberos configuration questions can be answered by using the DelegConfig tool that I wrote. However, that doesn't really help you find conflicts. If you are experiencing explicit misplaced SPNs, you might have to In support we see duplicate Service Principal Name issues quite frequently. This is an informational message. Output. I have an issue with duplicate SPN's for http/mail. Another common issue that can arise is the presence of duplicate SPNs within the network. here is what I have done so far C:\\Users\\tkaplan>setspn -x Processing entry 2 MSSQLSvc/ii-sql-01. Good morning / afternoon people of Spiceworks! I’m having some serious issues on my new infrastructure here - to give you a bit of background we have two domain controllers now, DC01 (virtual) and DC02 (physical). Here are the steps to remove duplicate Service Principal Names (SPNs) in Active Directory: SetSPN -T <DomainName> -Q */* SetSPN -T windowstechno. 4: 968: September 19, 2017 Non-existent AD This looks like a duplicate SPN issue. Everything OK But after a few minutes, the duplicate SPNs are coming back. Based on Microsoft documentation, starting in Windows Server 2012 R2 Domain Controllers will block the creation of duplicate SPN’s though it is still possible to have duplicate SPN’s on domain controllers running 2012R2 and later as described in this article. The Kerberos script may fail with the message Found duplicate SPNs (see If Kerberos does not recognise the Service Principal Name, it will not grant a ticket and so the login will not take place. txt -t 3268 -d dc=domainname,dc=local -l serviceprincipalname Service Principal Name (SPN) Issues: Duplicate or missing SPNs can cause authentication failures. Ldifde -f C:\spn. Resolution: To see why Kerberos is failing, you can enable additional Kerberos logging on the client side, to see what the issue is. One of the few ways to get a duplicate SPN without messing with dsHeuristics (don't plz) after Windows Server Hi, I am having an issue removing a duplicate SPN via setspn -d. Open PrzemyslawKlys opened this issue Aug 29, 2019 · 1 comment Open Nevertheless, my DC spits out the event that there is still this duplicate SPN with nice regularity. Permission Errors: If you encounter permission issues, ensure that you have administrative rights or the necessary delegated permissions. How can I permanently delete them? Where do they come from? In case it’s relevant, I re-named one of my DC’s–was named “Blue”, now named “Green”, to make way for Hi, I am looking to setup an ADFS for my company where we have 2 remote servers one for DC and one for File Share service. *Setspn. * Duplicate UPN values break synchronization between on-premises AD and Office 365. from the expert community at Experts Exchange. Windows. Have a duplicate SPN situation that I'm wondering about. Gary-D-Williams Duplicate SPN’s. <rootNS> (of type DS_SERVICE_PRINCIPAL_NAME). The setspn command can also discover inconsistencies with AD SPN records. I If you have duplicate SPN issues, use AdFind to find all computers with the name in the SPN. com' alias to either (physical) host's SPN list allows for Kerberos auth to one of the servers, but a duplicate SPN for A and B won't work (duh!). If you’re investigating the issue due to witnessing Event 11’s on your domain controller, the command should dump the duplicate entry listed in the event. This is one of the many causes of negotiated authentication to fall back from Kerberos to NTLM. According to my research the problem is a duplicate SPN in the Enterprise. It successfully prevents duplicate SPN and UPN when they are driven through administrative tools without requiring the tool to perform a Service Principal Names (SPNs) are not required to be unique across forests, but duplicate SPNs can cause authentication issues during across-forest authentication. Is there any way of implementing the same CIFS service alias for both hosts w/o running into duplicate SPN issues? Working through some issues with duplicate SPNs - using dbatools and setspn. Kerberos authentication will not be possible until a SPN is registered for the SQL Server service. Duplicate SPNs: Duplicate SPNs can cause authentication errors. The duplicate name is RPCSS/mis45 (of type DS_SERVICE_PRINCIPAL_NAME). localdom. Literally 99% of all Kerberos problems revolve around an incorrect, missing, or duplicate ServicePrincipalName (SPN). Duplicate SPNs means kerberos is already not working right for those machines so cleaning it up isn’t going to break anything worse. issue 2 is you Reply reply Top 1% Rank by size . So dns is also working. When faced with Kerberos authentication issues, follow these diagnostic and troubleshooting steps: Verify time synchronization across all devices. 3: 490: April 5, 2017 Major domain controller issues - possible duplicate SPN records. Things get more complicated with larger Active Directory environments as people change, new apps are Major domain controller issues - possible duplicate SPN records. After running a SETSPN -S command you may see Duplicate SPN found, aborting operation!. The duplicate name is Ldap/xyzdc1. 0 Group of duplicate SPNs found. Suggestions like running setspn -x. Windows Server 2012 R2 introduced restrictive checking for UPN and SPN uniqueness. Init&hellip; You could start with running DCDIAG on the DCs and see what errors you find. Spiceworks Community Major domain controller issues - possible duplicate SPN records. 4: 522: November 15, 2019 Service Principal Name Duplicate SPN Issue - SSPI Context Errors, cannot find bad SPN. One great example of this is MS SQL. The DC stops processing logins as a result. com:1433 is registered on these accounts: CN=Kaplan\, Tony,OU=System Accounts,OU=Domain The action you need to take depends on whether it lists Missing SPNs, Misplaced SPNs or Duplicate SPNs, and the causes are different. To find a particular service offered by a particular host within the domain. In the Windows Server 2008 version of SETSPN, we provide Nevertheless, my DC spits out the event that there is still this duplicate SPN with nice regularity. It is a complete ghost at this point. 3: 525: April 5, 2017 Major domain controller issues - possible duplicate SPN records. This is again a case of duplicate SPN. The Kerberos script may fail with the message Found duplicate SPNs (see Troubleshooting Kerberos). For an AD FS Farm setup, make sure that SPN HOST/AD FSservicename is added under the service account that's running the AD FS service. The Web server is configured to use NTLM authentication and not Negotiate. Service Principal Name (SPN) is registered incorrectly. Once that’s done, you should be able to handle the duplicate SPN. Common Issues. mydomain. company. Most likely, the script has been run previously. com (of type DS_SERVICE_PRINCIPAL_NAME). if there are any, you need to remove the duplicate SPNs. I've ran the powershell get-adcomputer to find any duplicate SPN's and searched for the object on both names. In my current environment I am running Windows 2016 at a 2016 I’m having some serious issues on my new infrastructure here - to give you a bit of background we have two domain controllers now, DC01 (virtual) and DC02 (physical). The duplicate name is cifs/dc1. However, there are some situations/tools that require the ability to bypass the duplicate SPN check in order to function properly. I've joined my OneFS cluster to my AD domain but in the events I get warnings saying there is missing SPNs. Another possible cause is a duplicate SPN in two different domains in the forest. Databases. exe is commonly used to create new SPNs, and functionally was built into the version released with Windows Server 2008 that adds a check for duplicates. ps1 queries the Kerberos configuration. But look at the far right, and there is a button to generate a script to fix the issue, or a button to just fix it outright. com:1433 is registered on these accounts: CN=Kaplan, Tony,OU=System Accounts,OU=Domain Issue 2: Intra-forest migration If you perform an intra-forest user migration that has service principal name (SPN) or user principal name (UPN) defined or intra-forest computer migration, the migration fails because the account still exists in the global catalog as the object is introduced in the target domain that has these attributes populated. 1345: boca, 1345: ojos/orejas, Relevant Log O I have several duplicate SPN’s associated with one of my DC’s. From a kerberos point of view, duplicate SPN would cause authentication issues, as the issued token against the SPN, is signed with the computer object and server's shared secret (password) to ensure that only In the past I have used numerous tools to look for duplicate SPNs. found 1 groups of duplicate SPNs. A prime example would be a third-party Active Directory migration tool or even the built in commands NETDOM and The real problem is not the deleting duplicate SPN entry, but to actually decide false entry With logged on PDC as domain admins, you can run setspn –x command from elevated command prompt to identify SPN duplication After that AD will show you all duplicate SPN entries, but you must know which entry to keep and which to be deleted, for that you @OZ • I means Farm not cluster sorry for the mistake. joe. How to troubleshoot Active Directory Replication issues Network. Major domain controller issues - possible duplicate SPN records. 5: 568: June 4, 2014 So. The DCs and SQL servers are 2012 R2. Each service that uses Kerberos authentication needs to have an SPN set for it so that clients If you use a domain user account, before you run Microsoft Dynamics 365 Server Setup, you may need to verify that the service principal name (SPN) is set correctly for that account, and if necessary, set the correct SPN. I could rename the server and add it to the . The Service Principal Name is on the wrong Active Directory account (Computer or User). Event ID 2974 is generated a couple of times a month, and the SPN for SQL server account has to be reset or it tries using NTLM instead of Kerberos. Here is the output of setspn -X: http/mail. Type setspn -D<SPN> <computer_name>, where SPN is the name of the duplicate SPN and computer_name is the name of the computer that is assigned the duplicate SPN. HOST/nfs I’m having some serious issues on my new infrastructure here - to give you a bit of background we have two domain controllers now, DC01 (virtual) and DC02 (physical). If you install MS SQL as an Administrator of the domain, it will add the MSSQLSVC SPN to the SQL the search for duplicate SPN is setspn -X If there are a lot of them, redirect to a notepad so you can search it if you add -F it will search the entire forest but there are additional permissions The service principal name (SPN) is an often-misunderstood aspect of Active Directory Domain Services that can lead to authentication issues when improperly managed. Windows The duplicate name is MSSQLSvc/DBServer. (truncated/sanitized) Note that you see the SPN (MSSQLSvc/server1. I've been googling and there were suggestions that the SPN might be mismatched. corp. I moved the SPN's from the old account to the new account, but there is one that I cannot add since it is a duplicate. 5: 597: June 4, 2014 Duplicate SPN not deleting. One has to either know all SPN's in the environment, track them or check each time whether it already exists or not. 5: 551: June It seems like I have an issue with duplicate SPN's on a Server 2016 environment (2 domain controllers). Once you start setting up and troubleshooting a 3-tier setup it is easy to end up trying new SPNs on new accounts, and forgetting to remove the original SPNs. [Cross post from my blog with a few corrections] . Site Home - TechNet Blogs. How to check if you have duplicate Upon researching I have found that it could be a possible duplicate SPN Issue, however here is the output from the setspn commands when run in the domain, so I don’t believe there is an issue with duplicates: setspn /Q http/sccm$ Checking domain DC=ourdomain,DC=local. Init The name of this computer ends with ADFS22. SPNs are usually associated with computers. When I am configuring the ADFS I have an No problem except I it is still saying duplicate spns exist. After the connection succeeds, all the related SPNs are shown in the following screenshot. For example: Say there is a service in Domain A that uses the SPN http/service. So the impact will be huge if your removed manually. Instead you can you this command to list the SPNs for all computer accounts and then look for duplicates associated with another computer. Shared service accounts can lead to SPN duplication issues and introduce complexities in troubleshooting SPN-related errors, emphasizing the importance of maintaining distinct accounts for each service instance. Both can cause Kerb auth to break and Windows uses Kerb for auth everywhere it can. Issue 3 We appear to have two AD's running. I wasn't able to remove the SPN using SETSPN, so I deleted the workstation's AD object. I am upgrading the primary domain controller and when I ran the ADFS wizard, I had to run the Microsoft Internal Database to run as System. Stack Exchange network consists of 183 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers. Does anyone have any suggestions to find and remove this AD Having issues with duplicate SPNs. I'm assuming if I work out this duplicate SPN issue, I can then move onto the mapped drive issue. Use the setspn command to list, add, or remove SPNs as needed. Duplicate SPN found, aborting operation! Find Duplicate SPN: A Service Principal Name (SPN) is a concept from Kerberos. Stack Exchange Network. Kerberos and SPN (Service Principal Name): Since DCDIAG reports RPC binding failures and mentions incorrect target subject names and wrong passwords, this is most likely a Kerberos SPN configuration issue. My example below shows that the SPN for the SQL Server is fine, but the AG Listener SPNs are not correct. Any help would be greatly appreciated. (See also: Windows Authentication, GroupShare and the requirement of setting a Service Principal Name) This is required in order for the client PC to identify/establish a communication and authenticate via Kerberos authentication to the server Cleaning up a variety of small blips from a Microsoft AD Health Check, and I’ve come across a duplicate SPN issue. the SPN is MSSQLSvc and is showing up on 2 accounts. Is the issue I’m having because of the duplicate spn’s? If so which set do I delete? The server listed in the setspn screenshot is the one that I’m having issues with. Use ADSIedit. Related topics Topic Replies Views Activity; Duplicate SPN not deleting. This may result The service principal name (SPN) is an often-misunderstood aspect of Active Directory Domain Services that can lead to authentication issues when improperly managed. In order to prevent this from occuring remove the duplicate entries for You’ll need to square away the duplicate name issue (rename one of the objects to something a little less atrocious). I was working in my lab environment this weekend, playing with some SQL Servers that I had built with PowerShell DSC a while ago. This can occur when the target server principal name (SPN) is registered on an account other than the account the target service is using. at least for a short while due to DNS and name conflicts. 4: i am trying to find a soloution for our duplicate SPN Problems. I am trying to run setspn -u -s host/adfs01. Check Active Directory for missing or duplicate SPNs. Issue 2: Intra-forest migration If you perform an intra-forest user migration that has service principal name (SPN) or user principal name (UPN) defined or intra-forest computer migration, the migration fails because the account still exists in the global catalog as the object is introduced in the target domain that has these attributes populated. Hi, I am having an issue removing a duplicate SPN via setspn -d. Entry 5 is processed. question, active Any duplicate SPN’s will be listed. (only after checking for duplicates first) -d Delete an entry from an account -x Search the domain for duplicate SPNs -q Query the domain for a specific SPN. And nslookup forward and reverse returns the expected server names. What is a Service Principal Name?Service principal names (SPN) is used by Kerberos to link a service to a service account. The issue is there is a disconnect between DC’s. Is No. active-directory-gpo, question. Duplicate SPNs can cause issues, including Kerberos authentication problems or application failures. contoso. If you have any other website/ Application running under the same host, you should add port numbers as well to avoid duplicate SPN issue. ; Maintenance: Regular checks for duplicate or misconfigured SPNs can be "The KDC encountered duplicate names while processing a Kerberos authentication request. No user action is required. domain ] for the SQL Server service. Remove SPN from the computer account SQL01. You can use the setspn -Q command to query if the service account (usually the DC's computer account) is registered with the correct SPN. therefor we have some duplicate SPNs which are coursing Problems after delete and restoring the Objects. SPNs are unique identifiers for the services running on the servers. Gary D Williams: What do you get if you do a “SETSPN -X” - This will display all the duplicate UPN’s in your AD environment. SPNs must be unique, so if an SPN already exists for a service on a server then you must delete the SPN Windows Server 2012 R2 Duplicate SPN issue. I have also discovered that there is a duplicate account registered for http/portal and its fqdn I am having an issue on one of my DCs. Our SCCM server has an SPN directly applied to its AD object and I can't figure out But the SPN tab is where the real fun is. I believe that the setspn command is having a Reason This is happening because there is a duplicate SPN on the service account and since serviceprincipalname attribute is a multi-valued property, when you add/remove all values are validated Skip to content One of the servers will not join the domain as the specified name (s-prd-dc3). Find answers to Duplicate SPN issue: not sure how to resolve. In this case you can either substitute the user samaccountname, or use AD Users and Computers, enable Advanced View, and delete the offending duplicate SPN from the Attribute Editor tab of the {"payload":{"allShortcutsEnabled":false,"fileTree":{"support/sql/database-engine/connect":{"items":[{"name":"media","path":"support/sql/database-engine/connect/media Duplicate SPNs can cause issues, including Kerberos authentication problems or application failures. 6 minute read. com and the same SPN exists in Domain B. Which I then ran setspn to check for duplicate spn’s. I'd like to know if anyone else has seen this and if I am on the right track with deleting and recreating the SPN. The SQL Server Network Interface library could not register the Service Principal Name (SPN) [ MSSQLSvc/server. Kerberos Issue - Anonymous Login. The account the SPN is registered for is not trusted for delegation in Active Directory. question, active-directory-gpo. If the other Services are running under domain accounts, like crmasyncservice, crmsandservice, do those also need the same SPN's created? Would this not create duplicates? Can't have duplicate SPNs if you want Kerberos auth to work. The explicit misplaced SPNs can cause issues in Kerberos authentication and prevent clients from connecting to the service. Now we have seen what it looks like when there is no Service Principal Name defined , and when the Service Principal Name is not unique in the forest. When multiple SPNs are assigned to the same service or host, it can confuse the authentication process and lead to unexpected behavior. com. DNS issues: Ensure that DNS is correctly resolving the names of domain controllers and virtual machines. There's no in-box method to block the addition of a duplicate SPN or UPN. Anyone has an idea to fix? Thanks! i’m trying to register the SPN to the AD-service-account. I have deleted each of them multiple times, using both setspn -D and ADSIedit, but after a few minutes these SPN’s all re-appear. bz:11 39 (of type DS_SERVICE_PRINCIPAL_NAME). 5: 596: June Hey everybody, I've been puzzled over this for almost a month; when running the ADFS configuration wizard I was presented with a duplicate SPN issue and informed I'd have to manually set it later. Click on the website and in the center panel, click on configuration editor. What about any duplicate SPN’s you have in AD that just aren’t causing problems yet but may one day. To identify duplicated accounts: you can use the command: setspn -q <service/server:port> ; to find SPN duplicate on the forest Duplicate SPN found - Troubleshooting Duplicate SPNs Symptoms. Once the SPNs are removed, rerun the KCM to verify that the SPN issues are resolved. Run setspn -X to identify the duplicate SPN. I fixed a few minor issues (DNS cleanup, a stale DC, wrong network profile, pretty typical stuff), but no joy. This allows a user to access a service without knowing the service So, duplicate SPNs are very bad, much in the same way that duplicate UPNs are bad. CN=SCCM,OU=Servers,OU=Company Duplicate SPN: You can encounter the situation when the same SPN is registered under different accounts in Active Directory. domain. you could configure both services to run under the same domain user account to prevent duplicate SPN issues. txt' on the DC. A service principal name (SPN) is a unique identifier of a service instance. When I run this command, I get no results: Get-ADComputer -Filter {serviceprincipalname -like ‘adfs22’} -Properties name,serviceprincipalname |select As we all know, the KDC’s cannot issue tickets for a particular service if there are duplicate SPN’s, and authentication does not work if the SPN is on the wrong account. For this reason, each SPN must point to exactly one Windows account. domain” (in my opinion, these is How To Find Your Duplicate SPN’s: Up until now, we’ve focused on troubleshooting duplicate SPN’s based on some given scenarios you might be having because you’ve seen KDC Event ID 4 or 11. Rather try to work out this, get the domain back to stable, and then work on Windows Server 2012 R2 Duplicate SPN issue. com because it's hosted on computer object and this account seems to be domain controller. The issue: The same name for a computer object exists on 2 or more domains, therefore there are multiple SPN duplicates across the forest. xyz. With SDL Trados GroupShare 2017 it is required to set a SPN for the service account running the GroupShare Services. iks. Use setspn -X to find and then setspn -D to delete duplicates. When I look at the SPN’s listed under server-03 I can see all the SPN’s of the existing server-02 name (aswell as server-03) I wasn’t aware renaming a DC would cause issues I believe the duplicate SPNs are because while in the renaming process clients and services may still try to access the old DC services under the old name. Make sure there are no duplicate service principal names (SPN) within the AD forest. I currently get errors in the system log on my Windows 2008 R2 domain controller daily, such as: Event ID: 11 Source Name: KDC The KDC encountered duplicate names while processing a Kerberos authentication request. Later versions of SETSPN actually check and report duplicates. The service principal name (SPN) is an often-misunderstood aspect of Active Directory Domain Services that can lead to authentication issues when improperly managed. mnivea. Note. To check for duplicate SPNs, you can use the setspn tool with the -X option. We are still using the same setup as part Looking at Event logs revealed that this was related to an Service Principal Name issue: WORKSTATION: Log Name: System Source: Microsoft-Windows-Security-Kerberos Date: 10/7/2013 3:59:14 PM I ran setspn command to show me the duplicate SPNs: setspn. Hey guys, having trouble finding duplicate SPN names on my 2008 domain controller and it is messing up some people's logins. Resolution. Duplicate SPN. 60 out of 5 [Comments (3)] 3 Responses to “The problem with duplicate SPNs – alternate working title A catch-all 'HOST/C. r/sysadmin. It's only the namespace that is Looking for duplicate SPN entries, I ran the command 'ldifde -d "dc=bkf,dc=internal" -r "servicePrincipalName=http*" -p subtree -l "dn,servicePrincipalName" -f output. This allows a client application to request that the service authenticate an account even if the client does not have the account name. I would like to The KDC encountered duplicate names while processing a Kerberos authentication request. If you can Server Configuration: When setting up or reconfiguring servers, administrators can use this module to ensure that SPNs are correctly set, preventing authentication issues. A reddit dedicated to the profession of Computer System Administration. This may result in auth Spiceworks Community Duplicate SPN for MSSQLSvc. I am trying to find a soloution to find and Report all SPNs and later to filter only the Duplicate SPN. If sql server database engine and agent are running with two different service account, do we need to follow any thing special while manually registering the SPN, means read service principle name and write service principle name permission should be given to only sql server database engine service account or to both(sql To comply with security standards, we changed the SQL account for SCCM and immediately had issues due to SPN's being on the old account. They are not. And delete the duplicated SPN and check if it helps. In a previous article, I had written about the problem of duplicate Kerberos SPN's (Service principal names) and how to identify them. nfs/admin. nslookup fileserver-alias Verifying Kerberos SPNs and Keytab Files. dom CN=ADFS01,OU=Servers,DC=localdom,DC=dom HOST/ADFS01. Diagnosing and Troubleshooting Steps. The process is performed within the overall structure, this process may take some time. To be safe, make note of the SPN that you're deleting in case you remove the wrong one. SPNs are used by Kerberos authentication to associate a service instance with a service logon account. Open Regedit. ; Troubleshooting: If services are failing to authenticate properly, the module can be used to diagnose and fix SPN-related problems. vbs to DelegConfig . If your domain account doesn't have necessary permissions to update Active Directory, use the Generate or Generate All button to generate the necessary script that you can hand over to your Active Directory administrator to remove the duplicate SPNs. dom localdom\adfssvc I am getting Checking domain localdom. 4261635 Did this article solve an issue for you? Select Rating. Rating 4. Experienced administrators learn to use the SETSPN utility to validate SPNs when authentication problems occur. First published on TechNet on Jun 11, 2008 Rob here. The web browser was not able to get a Kerberos ticket from Active Directory, and it defaults back to NTLM Credentials. In order to prevent this from occurring remove the duplicate entries for Duplicate SPN found, aborting operation! Cause. I was working in my lab environment this weekend, playing with some SQL Servers that I had built We have an issue with our domain where we are getting random duplicate SPNs for our SQL servers in AD. So, in this case you should add the name of ADFS farm as SPN on the service account as mentioned on the link in Report all Service Principal Name (SPN) and delegation configurations on the server. local:1433) and two objects (CN=SERVER1 & CN=SQL Admin). I can list all duplicates with setspn -x, and see three separate hits, all different resources on the same server. Issue can be reproduced with the following steps when the Middleware / WebCenter Portal is installed on a Windows Environment: Use the setspn -L <AccountName> command to check for duplicate SPNs. Have you tried JesseC's link yet. Feb 16, 2021. I eventually discovered a duplicate SPN registered (RPC/[SPN] and LDAP/[SPN]) on both a workstation and their DC. Duplicate SPN - Refers to a situation in which two or more SPNs are identical within a domain. An SPN is the protocol + service name + account, and this is the only account that is having this issue from what I can see, but there are no duplicate SPN’s on it. \Users\Administrator>setspn -X Checking domain DC=DOMAIN,DC=GLOBAL Processing entry 0 found 0 group of duplicate SPNs. discussion, windows-server. Ok, I`ll try doing it that way. setspn -X -F returnes nothing unecpected The overall structure "DC=domain,DC=int" is checked. Deletes the specified SPN from ServerAccount. 5: 593: June 4, 2014 KDC encountered duplicate names. Here’s an example of the command finding a duplicate entry. The Active Directory account that is running the service has updated / changed its password and you are experiencing the problem because of an Active Directory Replication Latency or Active Directory Replication problem. setspn -X rAthena Hash lastest Client Date 20220406 Server Mode Pre-Renewal, Renewal Result I use map_msg_spn [ Debug ] : Message #1346 not found for langtype 0. Possible missing SPNs: HOST/admin. New SQL 2022 Servers won't register SPN. prev next. LOCALDOM. This can happen when an AD computer object is reused in a restore like this. 2. Request a KB Article Environmental or User-specific Issues? Be sure to check the following: Make sure the service principal name (SPN) is only on the ADFS service account or gMSA: Setspn –L <service Account Name or gMSA name> Example Service Account: Setspn –L SVC_ADFS . The duplicate name is MSSQLSvc/IKSDB01. Kerberos authentication uses SPNs to associate a service instance with a service sign in account. ORG domain. Cancel SPN consistency (Duplicate SPN) #21. local -Q */* Existing After running a SETSPN -S command you may see Duplicate SPN found, aborting operation! The Kerberos script may fail with the message Found duplicate SPNs (see Troubleshooting Working through some issues with duplicate SPNs - using dbatools and setspn. This is known as a duplicate SPN issue. If it appears the SPN is registered to the correct account, search the entire forest for a duplicate SPN. domainname. This may result in authentication Attempting to create a Service Principal Name (SPN) for Kerberos Authentication for WebCenter Portal on Windows fails with error: Duplicate SPN found, aborting operation! STEPS. SPN: What is a service principal name? A service principal name (SPN) is a unique identifier for a service instance. local:63229 (of type DS_SERVICE_PRINCIPAL_NAME). The KDC encountered duplicate names while processing a Kerberos authentication request. but if i do so, i’ll get the output “duplicate SPN found, aborting operation”. local. You can view the entries for a single computer account by using ADSI Edit. HOST/admin. They are on user objects. Search syntax tips Provide feedback We read every piece of feedback, and take your input very seriously. ) Determine which object the spn should actually be delegated to. Windows Server 2012 R2 Duplicate SPN issue. we have a large foorest with 5 SubDomains in the forrest. One is supposed to be the master, the other is supposed to be a backup (there was a third as well, but that server is physically gone). discussion, microsoft-sql-server. theilmgroup. Below is a SS showing the . Learn how to use the setspn command line tool to manage service principal names in Active Directory and properly configure your service accounts. Verify the CNAME maps the alias hostname to the file server canonical name. I keep getting an event log entry stating I have a duplicate SPN. Windows return code: 0xffffffff There's no in-box method to block the addition of a duplicate SPN or UPN. It was a duplicate userprincipalname(UPN), not a duplicate ServicePrincipalName(SPN). setspn -d "spn" hostname would work if your spns are on computer objects. Init Kerberos uses SPNs to locate which Windows account the NAV Server is running under. \\server1\dfs or \\server2\dfs still work. SPNs are used to uniquely identify services that are running on servers in a Windows domain. exe -X -P Looked at results, yet the computername I was concerned was not listed. Environment: Windows domain: single forest, 3 DC's Mix of svr 2008/2012 There are numerous event log entries on mutiple servers that say: Proper SPN registration practices rely on each service having a unique identity, which is bolstered by employing separate service accounts. I’m having some serious issues on my new infrastructure here - to give you a bit of background we have two domain controllers now, DC01 (virtual) and DC02 (physical). More posts you may like r/sysadmin. SQL2012-backup and printserver2011 are both ADs. You can find that tool here . – AlwaysLearning. I ran the command 'isi auth ads spn check domainname. here is what I have done so far C:\Users\tkaplan>setspn -x Processing entry 2 MSSQLSvc/ii-sql-01. If the account on the SPN is the Tableau Server RunAs user, this warning can be ignored. These duplicate SPNs can trigger various types of alerts like "WinRS: Unauthorized, check username and password" or "WindowsServiceLog: failed collection - HTTP Unauthorized received on Kerberos" February 11, 2014 at 10:33 AM. 3: 523: April 5, 2017 Major domain controller issues - possible duplicate SPN records. Overview In Active Directory, a Service Principal Name (SPN) is a unique identifier for a service instance. During a DR of a fileserver, the system was added in with a duplicate SPN. The results are shown on screen and when an issue is identified a message is displayed which you can use to resolve the issue, using the This is useful in large, distributed single-forest, multi-domain environments running Windows Server 2012 R2 DCs to prevent issues with duplicate HOSTNAME\shortname SPN values on machines. windows-server, question. This may result in authentication failures or downgrades to NTLM.