ESXi host frequently disconnects from vCenter Server after upgrading ESXi to vSphere 7.0 Update 3

Products

• VMware vSphere ESXi

Issue/Introduction

The following might be observed after upgrading/patching ESXi to vSphere 7.0 Update 3:

• ESXi frequently disconnects from vCenter Server or shows as NotResponding
• Accessing the Host UI Client fails with below error message

503 Service Unavailable (Failed to connect to endpoint: [N7Vmacore4Http16LocalServiceSpecE:0x000000b136f2eae0] _serverNamespace = / action = Allow _port = 8309)

• Listing /var/core directory on ESXi host will show multiple hostd core dump files

• Log file /var/run/log/vobd.log will show entries similar to below snippets :

[YYYY-MM-DDTHH:MM:SS] [UserWorldCorrelator] 309002531us: [vob.uw.core.dumped] /bin/hostd(2103800) /var/core/hostd-zdump.001
[YYYY-MM-DDTHH:MM:SS] [UserWorldCorrelator] 313055552us: [vob.uw.core.dumped] /bin/hostd(2103967) /var/core/hostd-zdump.002
[YYYY-MM-DDTHH:MM:SS] [UserWorldCorrelator] 317109536us: [vob.uw.core.dumped] /bin/hostd(2104096) /var/core/hostd-zdump.003

• Log file /var/run/log/vmkernel.log will show entries similar to below snippets :

[YYYY-MM-DDTHH:MM:SS] cpu86:2104359)UserDump: 2635: hostd-worker: Dumping cartel 2104354 (from world 2104359) to file /var/core/hostd-zdump.001 ...
[YYYY-MM-DDTHH:MM:SS] cpu86:2104359)UserDump: 2823: hostd-worker: Userworld(hostd-worker) coredump complete.

Environment

VMware vSphere ESXi 7.0.3

Resolution

The issue is resolved in ESXi 7.0 Update 3d (19482537)

Workaround:

To workaround this issue :

• Restart management agents by following KB Restarting the Management agents in ESXi.