June 2025
Beginner to intermediate
1180 pages
37h 48m
English
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23.5 Two-Factor Authentication
When you use SSH, two authentication methods are common: a simple password (flexible, but not perfect in terms of security) or the use of keys as described previously (more secure, but requires that you always have a notebook with your private key at hand). A third option is to set up two-factor authentication.
In addition to the first factor (either a conventional password or a key), a second piece of information must then be passed during login. This can be, for example, a one-time key generated by an app on a smartphone or a key generated by an external token (such as the YubiKey).
With two-factor authentication (2FA), you increase the level of security. Unfortunately, this also makes logging in much more ...
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