You see the following messages in the sesa-agent log
ERROR [Logging] com.symantec.management.security.HostnameVerificationFailureException
SESA Agent Symc_ConfigProvider: Failed to bootstrap to primary management server https:
To resolve this issue adjust the hosts file in the SSIM and the collector. The host name listed in the collector hosts file must match the hostname as displayed in the Network settings tab in SSIM.
The hosts file entries should not be necessary if DNS is working properly.
To test if this is the issue, setup a hosts file entry. If the hosts file entry resolves the issue, the problem is name resolution.
After this change, bootstrap the agent to the SSIM appliance: How to bootstrap the Symantec Security Information Manager (SSIM) Agent on a collector computer
Another possible solution is that bootstrapping is disabled to that appliance.
When you bootstrap a collector you must be logged in to the collector machine with sufficient privileges to perform administrative functions. To test this, log in to the collector machine as root or administrator and test the bootstrapping procedure.