docs(tailscale): sysctl note (#32995)

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charts/stable/tailscale/docs/How-To-Guide.md

@@ -12,15 +12,26 @@ This guide doesn't cover using Tailscale with individual applications. While the
 
 ## Requirements
 
+### Tailscale 
 - Tailscale Account (Free accounts available at [Tailscale's Official website](https://www.tailscale.com))
-- Tailscale Truecharts Chart
 - Tailscale DNS setup for Talos Cluster Domain
 
-
 Generate a Tailscale Auth Key for your setup, easy to generate on the page below
 
 ![tailscale-auth-key](./img/How-To-Image-1.png)
 
+### Sysctl
+:::note[sysctl]
+
+This part is not needed for CLustertool setup with TalosOS.
+
+:::
+At some OS's it is required to set two `sysctl` values for proper acces to your local network (LAN). Check your OS documentation how this needs to be done.
+```
+net.ipv4.ip_forward = 1
+net.ipv4.conf.all.src_valid_mark = 1 
+```
+
 ## Tailscale Chart Setup
 
 ### Application name