/var/log/vmware/vcf/domainmanager/domainmanager.logof the SDDC Manager reports the following error:"errorCode": "BROWNFIELD_VCF_OPS_NODE_CERTIFICATE_VALIDATION.error" "message": "Unable to reach VCF Operations node [FQDN]. This could indicate a network connectivity issue or a certificate that does not include this address in its SAN field"The VCF 9.1 upgrade process performs strict validation of the VCF Operations node certificates. If the existing certificate does not explicitly include the FQDN, IP address, and shortname of all nodes in the VCF Operations cluster within the Subject Alternative Name (SAN) field, the validation task fails, preventing the upgrade from proceeding.
To resolve this issue, the VCF Operations certificate must be regenerated to include the missing SAN attributes for all cluster nodes.
Procedure
echo | openssl s_client -showcerts -connect [FQDN]:443 2>/dev/null | openssl x509 -noout -text | grep -A1 "Subject Alternative Name"If the upgrade task continues to fail after certificate rotation due to stale database records, ensure that you have cleared invalid metadata from the Fleet Lifecycle management database using the remediation script provided in KB 441858.