无法在 AIQUM 中添加集群，websocket 握手期间出现错误 DNS NXDOMAIN

Active IQ Unified Manager (AIQUM) 9.14+

• 无法在 Active IQ Unified Manager 中添加集群，GUI 错误：

Unable to add cluster datasource. This can occur if the clocks on the systems are not synchronized and the Active IQ Unified Manager HTTPS certificate start date is later than the date on the cluster, or if the cluster has reached the maximum number of EMS notification destinations.

• Server_acq.log：

2025-02-05 16:29:19,271 ERROR [default task-17168] c.n.u.CloudAgentConnectionUtil (CloudAgentConnectionUtil.java:223) - Failed to establish connection for cloud agent instance "UnifiedManager_XXXXXX-XXXX-XXXX-XXXXX-XXXXXX". Reason: AMQP transport failed for connection "UnifiedManager_XXXXXX-XXXX-XXXX-XXXXX-XXXXXX". Reason: Error during websocket handshake: DNS NXDOMAIN.

2026-08-05 12:24:26,806 ERROR [default task-299] c.n.s.a.s.r.s.i.AcquisitionFacadeSessionServiceImpl (AcquisitionFacadeSessionServiceImpl.java:905) - Fail to add data source for acquisitionUnitName: local, dataSourceName: ClusterIP, vendor:NetApp OCI Essentials, model: NetApp OCI Essentials, datasourceTypeId: 91, manual: 1, isActive: false, attrs: -- listing properties --
netappfoundation.numBuilderThreads=3
um.ems.rest.destination=UM_FQDN
com.netapp.oci.netapp.client.interfaces.data.EmsManagerException: Connection timed out: connect (errno=0) (errno=0)

2026-07-31 13:24:55,295 ERROR [default task-119961] c.n.s.a.s.r.s.i.AcquisitionFacadeSessionServiceImpl (AcquisitionFacadeSessionServiceImpl.java:916) - Failed to unregister ems event filter destination for UM_FQDN after failure to add datasource

• ocum-error.log

Common name in the host certificate is invalid 

• 通过 CLI 添加集群失败  ERROR: connect timed out