Also, if you want to check the certificate that is being presented by your host, this command could be helpful. SSH into the host or from the console as root
openssl s_client -connect esx01.test.lab:443 -showcerts -servername esx01.test.lab 2>/dev/null | openssl x509 -noout -text | grep -A 1 Subject\ Alternative
This should return something like the following where hopefully the hostname matches in the certificate:
X509v3 Subject Alternative Name:
DNS:esx01.test.lab
You'll have to Control-C to terminate the command, but it is a good test.
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Advanced Services Architect | VCF Division
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Original Message:
Sent: Oct 03, 2025 09:32 AM
From: Shahrouz Esmailpour Lahiji
Subject: error adding hosts on vcf9 installer
Doug, gave you a detailed step-by-step configuration for ESX 9 preparation.
I also encountered this issue, and I verified that the FQDN is configured correctly via DCUI and the ESX Host client.
If the correct FQDN is configured, then connect to the host by SSH and run the following commands to regenerate the certificate and restart the hosted and vpxa services. And you usually don't need to reboot the host!
# /sbin/generate-certificates
# /etc/init.d/hostd restart && /etc/init.d/vpxa restart
Hopefully, it helps you to solve the issue.