Linux · SSH: Keys, Config & Hardening

What does YubiKey SSH authentication need on the server side to actually verify a token's one-time password?

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More in SSH: Keys, Config & Hardening

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How do you run a single command on a remote host without opening an interactive shell, versus feeding a whole batch of commands to it non-interactively?

For automating ssh across many fresh hosts, the first-connect trust prompt gets in the way. Which option skips it, and which config file do such client options belong in?

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