When accessing SDDC Manager GUI login page, it does not show up.
SSH login to SDDC Manager is possible.
SDDC Manager 5.x
This might be caused by operationsmanager service being unresponsive due to running out of its heap memory.
To recover accessibility of the UI login page, restart operationsmanager service or reboot the SDDC Manager appliance.
The way to restart operationsmanager service:
1. SSH to SDDC Manager with vcf user
2. Switch to root user
su
3. Restart the service with following command
systemctl restart operationsmanager
If you did a precheck for adding multiple hosts before the issue, it might be caused by known issue. See SDDC Manager UI crashes and does not load after upgrade to VCF 5.2