=== d4 가 가리키는 기계(test-server)에 certbot 이 있나 ===
/usr/bin/certbot
NEXT LEFT LAST PASSED UNIT ACTIVATES

0 timers listed.
Pass --all to see loaded but inactive timers, too.
=== 실제로 certbot 이 있는 기계(kc-lab-edge) ===
certbot -> /usr/bin/certbot
--- 5. 갱신 자동화가 도는가 ---
NEXT                        LEFT     LAST PASSED UNIT          ACTIVATES
Thu 2026-09-17 17:06:05 UTC 10h left -    -      certbot.timer certbot.service

1 timers listed.
--- 이름이 배포판마다 다르다 ---
Thu 2026-09-17 17:06:05 UTC 10h left    -                           -            certbot.timer                certbot.service
--- 6. 배포판 기본 유닛에 훅이 있나 ---
# /lib/systemd/system/certbot.service
[Unit]
Description=Certbot
Documentation=file:///usr/share/doc/python-certbot-doc/html/index.html
Documentation=https://certbot.eff.org/docs
[Service]
Type=oneshot
ExecStart=/usr/bin/certbot -q renew --no-random-sleep-on-renew
PrivateTmp=true
--- renewal-hooks 디렉터리 ---
total 0
--- 지금 인증서가 있나 ---
Saving debug log to /var/log/letsencrypt/letsencrypt.log

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No certificates found.
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