The most typical status is Communicating. Any other statusindicates that the SIC communication is problematic.
For example, if the SIC status is Unknown then there is no connection between the Gateway and the Security Management server.
If the SIC status is Not Communicating, the Security Management server is able to contact the gateway, but SIC communication cannot be established.

Explanation
This command uninstall actual security policy (already installed)

Explanation/Reference:
Explanation :
ClusterXL uses the Multicast mechanism to associate the virtual cluster IP addresses with all cluster members. By binding these IP addresses to a Multicast MAC address, it ensures that all packets sent to the cluster, acting as a gateway, will reach all members in the cluster.
Reference:
https://sc1.checkpoint.com/documents/R76/CP_R76_ClusterXL_AdminGuide/7292.htm

Explanation
VPN key (to not be confused with pre-shared key that is used for authentication).
VPN trust entities, such as a Check Point Internal Certificate Authority (ICA). The ICA is part of the Check Point suite used for creating SIC trusted connection between Security Gateways, authenticating administrators and third party servers. The ICA provides certificates for internal Security Gateways and remote access clients which negotiate the VPN link.
VPN Domain - A group of computers and networks connected to a VPN tunnel by one VPN gateway that handles encryption and protects the VPN Domain members.
VPN Community - A named collection of VPN domains, each protected by a VPN gateway.
References: http://sc1.checkpoint.com/documents/R77/CP_R77_VPN_AdminGuide/13868.htm

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