@htdvisser, I understand what you say.
I asked a question because there could be a case even a few second down time may not be allowed.
Even if TTN components are set up in a distributed way, I wonder how each component can be set up in dual for fail over. For example, if a "Router-1" fails and shuts down, the other router ("Router-1-backup") is activated and works exactly like the "Router-1", and gateways and other TTN components do not even know if the "Router-1" is down and the entire network works as if the "Router-1" is still up and running.
If the Discover Server fails and shuts down, the entire private TTN network will be shut down until the Discovery Server is up and running again. For this reason, if there is a way to set up a dual Discovery Server (one active, the other as an inactive backup), it will be extremely helpful for reliability of the network.
I wonder if I could achieve HA just by setting up an L4 switch in front of two Discovery Servers (DS) that have the same configuration, and make one DS active and the other one inactive, and configure the L4 switch to route the traffic to the inactive DS once the active (primary) DS is down.
I wonder if I could do the same setup for each TTN component in this way to achieve HA for each TTN component.