[BUG] frr disconnects bgp neighbors when changing configuration

[netcedec]

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• [x] I have read the contributing guide lines at https://github.com/opnsense/core/blob/master/CONTRIBUTING.md
• [x] I am convinced that my issue is new after having checked both open and closed issues at https://github.com/opnsense/core/issues?q=is%3Aissue

Describe the bug

When changing any settings in Routing, for example adding a route, "Reload Service" is required, otherwise the changes are not applied. In the same pfsense the changes are applied on the fly. At this point all BGP neighbors are dropped, which is unacceptable in a running system.

To Reproduce

Steps to reproduce the behavior:

1. Go to 'Routing -> BGP '
2. Add neighbors, or prefix in prefix list.
3. The route is not announced or the neighbor does not come up
4. Click "Reload Service"
5. The neighborhood goes down for a few seconds and new routes are announced, graceful restart dont work.
6. See Error

   2024-03-27T17:19:17 Error   bgpd    [YAF85-253AP][EC 100663299] buffer_flush_available: write error on fd 2: Bad file descriptor    
   2024-03-27T17:19:17 Error   bgpd    [YAF85-253AP][EC 100663299] buffer_flush_available: write error on fd 2: Bad file descriptor

Expected behavior

The configuration change takes place immediately.

Describe alternatives you considered

You have to do a reload of the service to apply the settings, which causes the bgp neighborhood to drop with everyone.

Environment

OPNsense 24.1.6-amd64 OPNsense 23.7.12_5-amd64 Intel(R) Xeon(R) Gold 6242 CPU @ 2.80GHz Network VMXNET 3

[JSuenram]

Do you have "soft-reconfiguration" enabled on both sides?

[netcedec]

Do you have "soft-reconfiguration" enabled on both sides?

Yes