tmpfs.tech · all tracks · Networking

Enable IP forwarding persistently

Networking · medium · live throwaway Linux box · 3 tiered hints

Turn on IPv4 forwarding now AND make it survive a reboot (a sysctl drop-in under /etc/sysctl.d setting net.ipv4.ip_forward=1).

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Fastest verified solves

• Tien78s · ✦ no hints
• David319s · ✦ no hints

How it works

Press start and you get your own real, disposable Linux VM — in the browser terminal or over SSH. Work the task on a live system; tmpfs.tech grades your solution automatically against the actual machine state, then throws the box away. No install, free to try as a guest.

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FAQ

Is it free? Yes — play as a guest, no signup required to start.

Do I need to install anything? No. Everything runs in your browser, or connect over SSH if you prefer your own terminal.

How is it graded? Automatically and deterministically — your work is checked against the real state of the machine you worked on.