L2TP connections fail to reconnect after a initial connection failure via a Parent Interface.

[Ttfgggf]

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Describe the bug

L2TP fails to reconnect when dependent on another interface (in this case a WAN) when it originally goes down.
Even if they are IPv4 and IPv6 gateways set up for L2TP (marked as Upstream and 1 and 2 respectively).

This has happened across many reboots now.

Also the lack of the ability to use a domain name in the gateway field when setting up a L2TP connection (The IP address associated with my L2TP connection may change that is why I ask this)

To Reproduce

Set up a L2TP connection with a username and password.
Define the gateway.
Save the connection.
Leave the L2TP connection going for a few hours and then reboot.
Find that the connection may or may not come back up.

Expected behavior

L2TP Connection reattempts connection via parent interface after a failure and doesn't just stop.
Also full support of the use of a domain name for a gateway, not just an IP address.

Describe alternatives you considered

Originally, I was running opnSENSE virtually and thought maybe the hypervisor had an issue that was causing the L2TP disconnects.
I moved to physical hardware and the same thing happened.

Screenshots

Not available at the moment.
Due to another issue, I have faced with opnsense (self-caused) not related to this issue.

Relevant log files

Not available at the moment.
Due to another issue, I have faced with opnsense (self-caused) not related to this issue.

Additional context

Not available at the moment.
Due to another issue, I have faced with opnsense (self-caused) not related to this issue.

Environment

Software version used and hardware type if relevant, e.g.:

OPNsense 23.7.8 (amd64).
Intel i5-9500 Processer
16GB Ram
Dell Optiplex 3070

[csutcliff]

Same here, recently migrated a customer from pfSense and they have a backup WAN which is an L2TP tunnel via a 5G modem. 5G being what it is the connection can get interrupted from time to time. On pfSense the L2TP tunnel would dial again once the parent interface was back online but this is not the case on opnsense, I have to manually reload the L2TP from interfaces overview each time.