Forum Discussion
sensor service fails to start
Hello, i've installed MDI on all of our domain controllers and everything went fine. I am trying to install MDI our Entra connect server and our certificate authority server (which are not domain controllers) and the service is continually failing to start. Could someone please point me in the right direction on how to rectify this? I've tried:
- recreating the service account (3x),
- checking the service account with Test-ADServiceAccount (works fine from both member servers)
- verified the service account is given the right to log on as service.
The error log is very vague:
2025-11-13 19:05:30.0968 Error DirectoryServicesClient+<CreateLdapConnectionAsync>d__49 Microsoft.Tri.Infrastructure.ExtendedException: CreateLdapConnectionAsync failed [DomainControllerDnsName={FQDN of DC}]
at async Task<LdapConnection> Microsoft.Tri.Sensor.DirectoryServicesClient.CreateLdapConnectionAsync(DomainControllerConnectionData domainControllerConnectionData, bool isGlobalCatalog, bool isTraversing)
at async Task<bool> Microsoft.Tri.Sensor.DirectoryServicesClient.TryCreateLdapConnectionAsync(DomainControllerConnectionData domainControllerConnectionData, bool isGlobalCatalog, bool isTraversing)
2025-11-13 19:05:30.1124 Error DirectoryServicesClient Microsoft.Tri.Infrastructure.ExtendedException: Failed to communicate with configured domain controllers [ _domainControllerConnectionDatas={FQDN of DC}]
at new Microsoft.Tri.Sensor.DirectoryServicesClient(IConfigurationManager configurationManager, IDirectoryServicesDomainNetworkCredentialsManager domainNetworkCredentialsManager, IDomainTrustMappingManager domainTrustMappingManager, IRemoteImpersonationManager remoteImpersonationManager, IMetricManager metricManager, IWorkspaceApplicationSensorApiJsonProxy workspaceApplicationSensorApiJsonProxy)
at object lambda_method(Closure, object[])
at object Autofac.Core.Activators.Reflection.ConstructorParameterBinding.Instantiate()
at void Microsoft.Tri.Infrastructure.ModuleManager.AddModules(Type[] moduleTypes)
at new Microsoft.Tri.Sensor.SensorModuleManager()
at ModuleManager Microsoft.Tri.Sensor.SensorService.CreateModuleManager()
at async Task Microsoft.Tri.Infrastructure.Service.OnStartAsync()
at void Microsoft.Tri.Infrastructure.TaskExtension.Await(Task task)
at void Microsoft.Tri.Infrastructure.Service.OnStart(string[] args)4 Replies
The regular log just shows this:
(sorry, it won't allow me to paste the log in text form)
That is the top of the "error" log. It just repeats that over and over.
- EliOfek
Microsoft
There should be another log entry before that with an error code that says (hopefully) what went wrong when we tried to create the ldap connection, and which credential was u sed, against which DC.
The indicated error code is crucial for initial troubleshooting.I posted some more of the logs, there isn't anything before what i posted in the error log, that's the start. There also isn't anything indicating the failure point in the regular log. Can you advise next steps?
