Linux · SSH: Keys, Config & Hardening

Passphrase-protected keys are secure but prompt on every login. How does ssh-agent restore convenience, and what limits its reach?

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More in SSH: Keys, Config & Hardening

Why are telnet and rlogin considered obsolete, and what does ssh do differently to replace them?

The very first time you ssh to a new host, it prints a fingerprint and asks you to confirm. What is that step actually protecting you against, and what does answering yes do?

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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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