NSX UI is not displaying tiles for NSX Manager nodes

Products

• VMware NSX

Issue/Introduction

• NSX UI will load, but System -> Appliances will not show the tiles for NSX Manager nodes. 
• NSX Managers are on a specific network (e.g. #.#.#.#/24).
• Disconnected vCenter and ESXi hosts will be on a different network (e.g. #.#.#.#/24).
• There is a high number of Host Transport Nodes. 
• DNS servers used by the infrastructure nodes is in the same subnet as the vCenter. 
• One or more Compute Managers may be in "Down" state in System -> Fabric -> Compute Managers. 
• Host Transport Nodes owned by the Compute Manager which is down may be in "Disconnected" state in System -> Fabric -> Hosts.
• There may be some other unexpected network connectivity issues. 
• NSX Manager will report problems connecting to the vCenter:
  var/log/cm-inventory/cm-inventory.log
2025-07-17T11:52:16.425Z  INFO inventoryTasksScheduler2 CmInventoryService 5297 FABRIC [nsx@6876 comp="nsx-manager" level="INFO" subcomp="cm-inventory"] Retrieved cm config info from cm plugin instance, cmPluginStatusData= CmPluginStatusData{id=########-####-####-####-########3b17, server=<vCenter-server-FQDN>, cmPluginStatus=CmPluginStatusInfo{status=STARTED, cmConnectionStatus=DOWN, errors=[{"moduleName":"cm-inventory","errorCode":40204,"errorMessage":"IP address of Compute Manager <vCenter-server-FQDN> could not be determined. If the FQDN or thumbprint of the Compute Manager has changed, please edit the Compute manager information. The Compute Manager ID: ########-####-####-####-########3b17"}]}}
  
  
• NSX Manager has lost connection to the hosts on TCP 1234/1235:
  var/log/yslog:
2025-07-17T12:31:18.735Z <NSX-Manager-FQDN> NSX 2078 - [nsx@6876 comp="nsx-manager" subcomp="appl-proxy" tid="2078" level="INFO"] TnConnMgr: OnServerConnectionUpDown: ConnInfo:{id: 3215, pr: normal, remote endpoint ids:[########-####-####-####-########1eba], remote services:[vmware.nsx.cli.MetricsCliService, vmware.nsx.cli.ProxyConfigCliService, vmware.nsx.messaging.MessagingClientService, vmware.nsx.rpc.RpcCliService, vmware.nsx.daemon.DaemonHealth], net: {id: 3215, pr: normal, side: server, endpoint: ssl://0.0.0.0:1234, local-ep: ssl://0.0.0.0:1234, peer-ep: ssl-tcp://#.#.#.#:18111, peer-auth: {certificate sha256 '############################################################c205'}}} Status:Down
2025-07-17T12:31:18.735Z <NSX-Manager-FQDN> NSX 2078 - [nsx@6876 comp="nsx-manager" subcomp="appl-proxy" tid="2078" level="INFO"] TnConnMgr: service ep unix:///var/run/vmware/appl-proxy/aph.sock, local ep ssl://0.0.0.0:1234
2025-07-17T12:31:28.735Z cfgAgent[2101438]: NSX 2101438 - [nsx@6876 comp="nsx-controller" subcomp="cfgAgent" tid="9B3C4DC0" level="info"] Decoder: Received CCP_SESSION msg (Operation SET): ccp_id {   left: ################4069   right: ################9000 } ip {   ipv4: #.#.#.# } server_port: 1235 fqdn:  state: DISCONNECTED master: 1 failure_reason: CONNECTION_TIMED_OUT
  
  
• NSX Manager will show a high number of disconnected hosts:
  var/log/syslog:
2025-07-17T12:04:20.940Z  INFO ForkJoinPool.commonPool-worker-27 HostPrepServiceFabricDeploymentServiceImpl 5397 FABRIC [nsx@6876 comp="nsx-manager" level="INFO" subcomp="manager"] Heartbeat status is down. Returning HOST_DISCONNECTED status for node : ########-####-####-####-########a2c8
  
  
• Logs below indicate timeout of UI, causing the tiles not to load:
  var/log/syslog:
2025-07-17T12:35:50.202Z <NSX-Manager-FQDN> NSX 5397 SYSTEM [nsx@6876 audit="true" comp="nsx-manager" level="INFO" subcomp="manager"] UserName:'admin' ModuleName:'common-services' Operation:'GET@/api/v1/ui-controller/cluster-nodes-aggregate-info' Operation status: 'failure' Error: General error has occurred.

Environment

VMware NSX

Cause

• This behaviour is by design. 
• NSX manager is prioritizing re-connect of the infrastructure nodes.
• If there is a high number of Host Transport Nodes in disconnected state, the re-connect attempts will cause internal timeout of the UI calls for cluster-nodes-aggregate-info.
• Due to this, NSX Manager tiles will not be displayed by the UI.

Resolution

Please ensure there are no connectivity issues between NSX Manager and the Compute Manager(s), Host Transport Nodes and DNS server(s).