i am trying to upgrade a cluster of two ESXi hosts from version 6.0U2 to 6.5U1 using vsphere update manager 6.5, but the remediation process is stuck on 21%.
i have tried the remediation on the cluster and on the first server in the cluster, same issue happens.
note: the host is not entering maintenance mode. is there any port that should be open in order to make the communication between the update manager and the ESXi host ?
thank you in advance