What is <UNKNOWN> process with PID 0 making network connections?

General system Newbie
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What is this UNKNOWN process with PID 0 making network connections?

I can see this process making connections, sending and receiving data:

Screenshot From 2025-09-13 21-52-01
Screenshot From 2025-09-13 21-52-01958×478 15.8 KB

Should I nuke my system and burn my laptop? :grimacing:

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There are two tasks with specially distinguished process IDs: PID 0 is used for swapper or sched, which is part of the kernel and is a process that runs on a CPU core whenever that CPU core has nothing else to do.[1] Linux also calls the threads of this process idle tasks.

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The UNKNOWN process with PID 0 making network connections is usually seen when monitoring tools show a network connection, but cannot associate it with a specific user-space process, resulting in the PID being reported as 0 or as “UNKNOWN”. In most operating systems, including Arch Linux and other Linux distributions, PID 0 does not correspond to a typical user-space process, but is reserved for kernel-related tasks or system-level operations.

https://www.baeldung.com/linux/network-processes-with-no-pid

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Thanks for the reply! But as I understand, it wouldn’t need to make network connections. Or am I wrong?

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Thanks @swh! That makes sense, at least somewhat, to me. Time to dig deeper and educate myself.

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Looks like it may be related to firewall rules and/or VPN (openvpn).

I use both. Looking further…