Signing several files one after another, you are asked for your GnuPG passphrase only the first time. Which component caches it, and takes default-cache-ttl in ~/.gnupg/gpg-agent.conf?
LPIC-1 Exam 102-500, objective 110. Security easy
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Treat it as a good draft rather than as settled fact, and read the source below before you rely on it. It is not used in mock exams here — only questions a person has signed for are.
How these questions are written — where each question comes from, what the verification ledger records, and what happens when one is found wrong.
The options
Correct gpg-agent
Correct. Since GnuPG 2 every private-key operation goes through gpg-agent, which holds the unlocked key material and expires it after default-cache-ttl seconds of disuse, up to max-cache-ttl.
Not correct dirmngr
Wrong. dirmngr is the GnuPG component that handles network access, such as keyserver lookups and certificate revocation lists. It never sees a passphrase.
Not correct ssh-agent
Wrong. ssh-agent caches SSH private keys for the SSH client. gpg-agent can be configured to take over that role with enable-ssh-support, but ssh-agent itself knows nothing about GnuPG keys.
Not correct gpgconf
Wrong. gpgconf inspects and modifies the configuration of the GnuPG components, and gpgconf --kill gpg-agent is a common way to restart the agent. It stores no secrets of its own.
Why
gpg-agent is to GnuPG what ssh-agent is to SSH: the private keys stay in the agent's memory, and gpg asks it to perform each decryption or signature. The caching interval is set with default-cache-ttl and default-cache-ttl-ssh in ~/.gnupg/gpg-agent.conf, and the agent must be told to reload the file, for example with gpgconf --reload gpg-agent. Everything else under ~/.gnupg, including the keyrings and the private-keys-v1.d directory, should be mode 700 and owned by the user.
Where this comes from
- Cited
- manual page gpg-agent(1)
Practise this
Reading one question is not practice. The trainer will draw a short set from objective 110 and space the ones you get wrong.
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