8.5 Reconnecting a device that was automatically blocked from the network
If a device is automatically blocked from the network because of the network policy or the expiration of the network control list, the device can be reconnected to the network.
Devices can be automatically blocked from the network on the following occasions:
-
An attempt is made to connect devices to networks where connection is not allowed.
-
A security policy violation occurs.
-
It is outside the period permitted by the network control list.
-
The network control list has been deleted.
The following methods can be used to reconnect devices blocked from the network:
- Allow network connections by setting devices to be managed or excluded.
-
If the network monitor does not allow newly discovered devices to connect to the network, the discovered devices are not allowed to connect to the network but are registered in the network control list and blocked from the network automatically. If you check the discovered devices and set the devices to be managed or excluded, the devices are recognized as devices within the organization, and the network control list setting automatically changes to allow network connections. This allows the devices to connect to the network.
- Implement security measures to make sure that network connections are automatically allowed.
-
If you specify security policy settings by selecting Action Items and then Network Connection Control, network connections are automatically blocked depending on the judgment. In this case you should implement security measures. The next time a judgment is made, devices can be connected to the network if they comply with the security policy.
- Change the period in the network control list during which to allow network connections.
-
If a network connection period is defined in the network control list, network connections are automatically blocked outside that period. If devices need to connect to the network, change the period to allow network connections. Outside the network connection period, the icon
is displayed to indicate that devices are unavailable.
- Reregister the network control list to allow network connections.
-
If you delete a device or hardware resource, the corresponding network control list is automatically deleted. If you then attempt to reconnect a device to the network, the network connections will be blocked automatically if the network monitor is configured to disallow network connections of new devices. In this case, change the network control list setting of the discovered devices to allow network connections, so that the devices can connect to the network.
If an agent is installed on a computer and you have specified security policy settings by selecting Action Items and then Network Connection Control, the network connections of that computer are controlled after reconnection according to a security judgment. To allow devices to reconnect automatically, make sure that they comply with the security policy.
- Tip
-
In addition to the reconnection methods above, devices can also be manually reconnected.
You can forcibly allow blocked devices to connect to the network. For details on how to allow network connections manually, see 8.3 Allowing network connections.