Unable to add a new esxi host to vCenter - Failed to connect to the remote host, reason = rpc_s_no_memory

Products

• VMware vSphere ESXi

Issue/Introduction

Adding new ESXi host to vCenter fails with following:

A general system error occurred: Unable to get signed certificate for host name 'your_esxi_fqdn' ip '**.**.*.**': Error: Failed to connect to the remote host, reason = rpc_s_no_memory

In the vpxd.log you see the following error:

2025-03-27T14:15:58.074+01:00 info vpxd[35613] [Originator@6876 sub=Default opID=*******-*******-auto-******-h5:********-**] [VpxLRO] -- ERROR
task-36694108 -- certificateManager -- vim.CertificateManager.refreshCertificates: vmodl.fault.SystemError:
--> Result:
--> (vmodl.fault.SystemError) {
-->    faultCause = (vmodl.MethodFault) null,
-->    faultMessage = <unset>,
-->    reason = "Unable to get signed certificate forhost name 'your_esxi_fqdn' ip '**.**.*.**': Error: Failed to connect
 to the remote host, reason = rpc_s_no_memory (0x16c9a012). (382312466)
--> "
-->    msg = ""
--> }
--> Args:
-->
--> Arg host:
--> (ManagedObjectReference) [
-->    'vim.HostSystem:********-****-****-*****-***********:host-*****'
--> ]

 

 

 

Environment

vCenter 7x
vCenter 8x

Cause

Exhaustion of vmcad memory on vCenter leads to the vCenter being unable to generate a certificate for the ESXi host when connecting it.

Resolution

A. Restart vmcad service:

service-control --restart vmcad

B. Reboot the vCenter

C. Workaround to get the host connected immediately and reboot later:

Switch the advanced vCenter setting vpxd.certmgmt.mode to thumbprint so that vCenter can connect the host regardless of presented certificate