ACC related tables specific to Agents of the clone source instance should be excluded in clonesDescriptionAgent installs are tied to instance-specific MID Servers/URLs. MID Servers, and their record, including extensions, are preserver. But clones don't exclude or preserve the Agent records, CIs and relationships, due to potential problems with excluding/preserving only some CMDB classes. This means any records for the agents for the clone target instance will no longer exist, and those Agents would need to check in with the instance after the clone, as if it was for the first time, for their records to be recreated. However lots of background table records specific to the Agents of the clone source instance are copied over in clones as well, and should not be. Policy and check definitions could have changed due to a clone, as the target instance will now have the policies and checks from the source instance, and also now be upgraded/downgraded to whatever instance and app version the source instance was. ACC Policies would need recalculating from scratch after a clone, so these should be excluded in clones. When Agents reconnect, and Policies are recalculated, the data in these tables will be renewed.sn_agent_policy_statesn_agent_policy_clientssn_agent_policy_proxy_agent_mappingsn_agent_policy_monitored_cis These additional table records, and possibly more, are currently copied over in clones, and are not relevant to the target instance's Agents/MIDs.sn_agent_agent_registrationsn_agent_capability_m2msn_agent_agents_connected_to_cmdb_ci_computerand probably moreSteps to Reproduce Install 2 instances, with a MID Server, and Agents. These might not be the same instance version, or have the same versions of ACC related apps.Clone one over the other. Expected behaviour:Ideally all records specific to an agent install should be excluded and preserved in the clone, like MID Server records are. In practice this is not possible due to clone restrictions. However most records for Agents in the clone source instance could be excluded, to make the tables tidier, with only good records, and easier to use when investigating issues. Actual behaviour:Many records, especially to do with Policy calculation, are copied in clones. These are effectively orphaned, have broken references, nonexistant agent ids, invalid domains, etc.WorkaroundThis problem is currently under review and targeted to be fixed in a future release. Subscribe to this Known Error article to receive notifications when more information will be available.Related Problem: PRB1866874