public void removeManagedConnection(TVC con) {
    boolean wasInList = managedConnections.remove(con);
    
    if(!wasInList) {
      throw new RuntimeException("Tried to remove connection which wasn't in list for firewall: con=" + con +" fw=" +this);
    }
    
    managedIntencity -= con.getIntencity();
    con.setManagerFirewallId(NO_FIREWALL);
  }