A data center experiences a power outage that results in the reboot of all ESXi servers, including the software firewall's virtual machine (VM). Subsequently, there is a notable decrease in performance. Most end users complain of being unable to access the internet. The system engineer is still able to log in to the firewall management console smoothly.
What is most likely causing this issue?
After a power outage and reboot, it's likely that the dataplane disk partitions are unable to mount, which would lead to issues with packet processing and could explain the degraded performance and internet access problems. The system engineer's ability to log in to the firewall management console suggests that the control plane is operational, but problems with the dataplane could be causing the observed issues.
A "Performance" and "Most end users complain of being unable to access the internet". can be explained by the fact that the maximum number of sessions is limited if the firewall is not licensed. other answers do not make sense.