network can reachable and no error logs in DC, only having the time sync warning log, and dcdiag views below: Performing initial setup: * Identified AD Forest. Done gathering initial info. Doing initial required tests Testing server: Default-First-Site-Name\SH-ABCD Starting test: Connectivity ......................... SH-ABCD passed test Connectivity Doing primary tests Testing server: Default-First-Site-Name\SH-ABCD Starting test: Advertising Fatal Error:DsGetDcName (SH-ABCD) call failed, error 1722 The Locator could not find the server. ......................... SH-ABCD failed test Advertising Starting test: FrsEvent ......................... SH-ABCD passed test FrsEvent Starting test: DFSREvent There are warning or error events within the last 24 hours after the SYSVOL has been shared. Failing SYSVOL replication problems may cause Group Policy problems. ......................... SH-ABCD failed test DFSREvent Starting test: SysVolCheck [SH-ABCD] An net use or LsaPolicy operation failed with error 53, The network path was not found.. ......................... SH-ABCD failed test SysVolCheck Starting test: KccEvent ......................... SH-ABCD passed test KccEvent Starting test: KnowsOfRoleHolders ......................... SH-ABCD passed test KnowsOfRoleHolders Starting test: MachineAccount Could not open pipe with [SH-ABCD]:failed with 53: The network path was not found. Could not get NetBIOSDomainName Failed can not test for HOST SPN Failed can not test for HOST SPN ......................... SH-ABCD passed test MachineAccount Starting test: NCSecDesc ......................... SH-ABCD passed test NCSecDesc Starting test: NetLogons [SH-ABCD] An net use or LsaPolicy operation failed with error 53, The network path was not found.. ......................... SH-ABCD failed test NetLogons Starting test: ObjectsReplicated ......................... SH-ABCD passed test ObjectsReplicated Starting test: Replications ......................... SH-ABCD passed test Replications Starting test: RidManager ......................... SH-ABCD passed test RidManager Starting test: Services ......................... SH-ABCD passed test Services Starting test: SystemLog A warning event occurred. EventID: 0x00000024 Time Generated: 03/22/2021 16:12:50 Event String: The time service has not synchronized the system time for the last 86400 seconds because none of the time service providers provided a usable time stamp. The time service will not update the local system time until it is able to synchronize with a time source. If the local system is configured to act as a time server for clients, it will stop advertising as a time source to clients after 0 seconds. The time service will continue to retry and sync time with its time sources. Check system event log for other W32time events for more details. Run 'w32tm /resync' to force an instant time synchronization. You can control the frequency of the time source rediscovery using ClockHoldoverPeriod W32time config setting. Modify the EventLogFlags W32time config setting if you wish to disable this message. ......................... SH-ABCD passed test SystemLog Starting test: VerifyReferences ......................... SH-ABCD passed test VerifyReferences Running partition tests on : ForestDnsZones Starting test: CheckSDRefDom ......................... ForestDnsZones passed test CheckSDRefDom Starting test: CrossRefValidation ......................... ForestDnsZones passed test CrossRefValidation Running partition tests on : DomainDnsZones Starting test: CheckSDRefDom ......................... DomainDnsZones passed test CheckSDRefDom Starting test: CrossRefValidation ......................... DomainDnsZones passed test CrossRefValidation Running partition tests on : Schema Starting test: CheckSDRefDom ......................... Schema passed test CheckSDRefDom Starting test: CrossRefValidation ......................... Schema passed test CrossRefValidation Running partition tests on : Configuration Starting test: CheckSDRefDom ......................... Configuration passed test CheckSDRefDom Starting test: CrossRefValidation ......................... Configuration passed test CrossRefValidation Running partition tests on : ABCD Starting test: CheckSDRefDom ......................... ABCD passed test CheckSDRefDom Starting test: CrossRefValidation ......................... ABCD passed test CrossRefValidation Running enterprise tests on : ABCD.com Starting test: LocatorCheck Warning: DcGetDcName(GC_SERVER_REQUIRED) call failed, error 1722 A Global Catalog Server could not be located - All GC's are down. Warning: DcGetDcName(PDC_REQUIRED) call failed, error 1722 A Primary Domain Controller could not be located. The server holding the PDC role is down. Warning: DcGetDcName(TIME_SERVER) call failed, error 1722 A Time Server could not be located. The server holding the PDC role is down. Warning: DcGetDcName(GOOD_TIME_SERVER_PREFERRED) call failed, error 1722 A Good Time Server could not be located. Warning: DcGetDcName(KDC_REQUIRED) call failed, error 1722 A KDC could not be located - All the KDCs are down. ......................... ABCD.com failed test LocatorCheck Starting test: Intersite ......................... ABCD.com passed test Intersite