SFTP, root access and sudo

Suppose you log into a server with your own SSH user, have password-less sudo access and want to access files as root over SFTP.

Your attempt would probably look like this:

# sftp user@remote
Connected to remote.
sftp> cd /root
sftp> ls
remote readdir("/root"): Permission denied
sftp> sudo ls
Invalid command.

Not possible, right?

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Transcoding a HDR video with tonemapping

Before HDR came into wider use, working with video was easier. You didn't have to care about colorspaces [1], it would display fine everywhere and working with it was painless. Ok, this is oversimplified. But you get the point.

With HDR it's not so simple anymore: To display it a process called tonemapping needs to be applied and you even need a HDR-capable output device in order for a meaningful difference to be visible (compared to SDR, Standard Dynamic Range).

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Putting a systemd service behind a VPN

It recently occurred that I had the need to route all traffic by a certain application through a VPN. While premade solutions for this exist using Docker (especially in combination with BitTorrent clients), I preferred looking for something that really just isolates what is needed and leaves the rest alone.

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