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It is possible to use the administrative Administrative distance to set up an IKEv2 connection in parallel to an existing IKEv1 connection. After the IKEv2 connection has been established, the lower value means it becomes active. If the IKEv2 connection cannot be established, the IKEv1 connection is still there to be used. This guarantees permanent access via VPN without the need for an on-site visit.
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