tailscale/tsnet
Anton Tolchanov db34cdcfe7 cmd/tailscale/cli: add a risk message about rp_filter
We already present a health warning about this, but it is easy to miss
on a server when blackholing traffic makes it unreachable.

In addition to a health warning, present a risk message when exit node
is enabled.

Example:

```
$ tailscale up --exit-node=lizard
The following issues on your machine will likely make usage of exit nodes impossible:
- interface "ens4" has strict reverse-path filtering enabled
- interface "tailscale0" has strict reverse-path filtering enabled
Please set rp_filter=2 instead of rp_filter=1; see https://github.com/tailscale/tailscale/issues/3310
To skip this warning, use --accept-risk=linux-strict-rp-filter
$
```

Updates #3310

Signed-off-by: Anton Tolchanov <anton@tailscale.com>
2025-06-10 07:38:06 +01:00
..
example tsnet: split user facing and backend logging 2024-05-10 15:29:13 -07:00
depaware.txt cmd/tailscale/cli: add a risk message about rp_filter 2025-06-10 07:38:06 +01:00
example_tshello_test.go tsnet: add examples (#8289) 2023-07-19 12:36:49 -04:00
example_tsnet_test.go tsnet: split user facing and backend logging 2024-05-10 15:29:13 -07:00
packet_filter_test.go tsnet: add test for packet filter generation from netmap 2025-05-08 17:18:30 +01:00
tsnet_test.go tsnet: use test logger for testcontrol and node logs 2025-03-21 12:33:36 +00:00
tsnet.go tsnet: remove an expired configuration-path migration step (#16120) 2025-05-28 14:12:24 -07:00