[os-tailscale] Tailscale Interface Consistent Flapping

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Describe the bug

Tailscale's interface seems to go down/up around every 6 hours aligning with the release of 26.1.3 / os-tailscale 1.4

I have not been able to find any triggers for the issue and no deeper tailscale logs are to be found. I've seen the behavior on two separate opnsense hosts.

Version first noticed: 26.1.3 / os-tailscale 1.4
Current version: OPNsense 26.1.7-amd64 / os-tailscale 1.4

To Reproduce

Sequence of when Tailscale's interface goes down/up

2026-05-04T15:00:08-05:00 kernel - - - <6>[363793] tun0: changing name to 'tailscale0'
2026-05-04T15:00:08-05:00 kernel - - - <6>[363793] tun0: link state changed to UP
2026-05-04T15:00:08-05:00 kernel - - - <6>[363793] tailscale0: link state changed to DOWN
2026-05-04T15:00:08-05:00 suricata 30744 - - [101636] -- error code -1 The interface disappeared

History of Tailscale's interface going down around every 6 hours

2026-05-04T15:00:08-05:00 suricata 30744 - - [101636] -- error code -1 The interface disappeared
2026-05-04T09:06:45-05:00 suricata 30744 - - [101636] -- error code -1 The interface disappeared
2026-05-04T03:11:04-05:00 suricata 30744 - - [101636] -- error code -1 The interface disappeared
2026-05-03T21:18:25-05:00 suricata 30744 - - [101636] -- error code -1 The interface disappeared
2026-05-03T15:41:31-05:00 suricata 30744 - - [101636] -- error code -1 The interface disappeared
2026-05-03T09:57:15-05:00 suricata 30744 - - [101636] -- error code -1 The interface disappeared
2026-05-03T04:06:16-05:00 suricata 30744 - - [101636] -- error code -1 The interface disappeared
2026-05-02T22:09:34-05:00 suricata 30744 - - [101636] -- error code -1 The interface disappeared
2026-05-02T16:35:01-05:00 suricata 30744 - - [101636] -- error code -1 The interface disappeared
2026-05-02T10:50:22-05:00 suricata 30744 - - [101636] -- error code -1 The interface disappeared
2026-05-02T04:59:40-05:00 suricata 30744 - - [101636] -- error code -1 The interface disappeared
2026-05-01T23:08:39-05:00 suricata 30744 - - [101636] -- error code -1 The interface disappeared
2026-05-01T17:20:42-05:00 suricata 30744 - - [101636] -- error code -1 The interface disappeared
2026-05-01T11:47:29-05:00 suricata 30744 - - [101636] -- error code -1 The interface disappeared
2026-05-01T06:03:31-05:00 suricata 30744 - - [101636] -- error code -1 The interface disappeared
2026-05-01T00:05:33-05:00 suricata 30744 - - [101636] -- error code -1 The interface disappeared

Expected behavior

I expect the Tailscale interface to not flap

The report provides no file, test, or entry point; start by locating the os-tailscale plugin and reviewing the supplied kernel and Suricata timestamps. Done means identifying the cause of the recurring Tailscale interface flap and demonstrating stable interface operation with relevant logs or a regression test.