Get SSL Certificate (Let's Encrypt)2021/04/30 |
Get SSL Certificates from Let's Encrypt who provides Free SSL Certificates.
Refer to the details for Let's Encrypt official site below.
⇒ https://letsencrypt.org/
The expiration date of a cert is 90 days.
However, Systemd Timer which checks and updates certificates is included in Certbot pckage and you don't need to update manually. |
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[1] | Install Certbot Client which is the tool to get certificates from Let's Encrypt. |
[root@dlp ~]# dnf -y install certbot
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[2] | Get certificates. It needs Web server like Apache httpd or Nginx must be runing on the server you work. If no Web server is running, skip this section and Refer to [3] section. Furthermore, it needs that it's possible to access from the Internet to your working server on port 80 because of verification from Let's Encrypt. |
# for the option [--webroot], use a directory under the webroot on your server as a working temp # -w [document root] -d [FQDN you'd like to get certs] # FQDN (Fully Qualified Domain Name) : Hostname.Domainname
# if you'd like to get certs for more than 2 FQDNs, specify all like below # ex : if get [srv.world] and [www.srv.world] # ⇒ [-d srv.world -d www.srv.world]
certbot certonly --webroot -w /var/www/html -d www.srv.world Saving debug log to /var/log/letsencrypt/letsencrypt.log Plugins selected: Authenticator webroot, Installer None Enter email address (used for urgent renewal and security notices) # for only initial using, register your email address and agree to terms of use # specify valid email address (Enter 'c' to cancel): root@mail.srv.world Starting new HTTPS connection (1): acme-v01.api.letsencrypt.org ------------------------------------------------------------------------------- Please read the Terms of Service at https://letsencrypt.org/documents/LE-SA-v1.2-November-15-2017.pdf. You must agree in order to register with the ACME server at https://acme-v01.api.letsencrypt.org/directory ------------------------------------------------------------------------------- # agree to the terms of use (A)gree/(C)ancel: A ------------------------------------------------------------------------------- Would you be willing to share your email address with the Electronic Frontier Foundation, a founding partner of the Let's Encrypt project and the non-profit organization that develops Certbot? We'd like to send you email about EFF and our work to encrypt the web, protect its users and defend digital rights. ------------------------------------------------------------------------------- (Y)es/(N)o: Y Starting new HTTPS connection (1): supporters.eff.org Obtaining a new certificate Performing the following challenges: http-01 challenge for www.srv.world Using the webroot path /var/www/html for all unmatched domains. Waiting for verification... Cleaning up challenges IMPORTANT NOTES: - Congratulations! Your certificate and chain have been saved at: /etc/letsencrypt/live/www.srv.world/fullchain.pem Your key file has been saved at: /etc/letsencrypt/live/www.srv.world/privkey.pem Your cert will expire on 2021-07-31. To obtain a new or tweaked version of this certificate in the future, simply run certbot again. To non-interactively renew *all* of your certificates, run "certbot renew" - Your account credentials have been saved in your Certbot configuration directory at /etc/letsencrypt. You should make a secure backup of this folder now. This configuration directory will also contain certificates and private keys obtained by Certbot so making regular backups of this folder is ideal. - If you like Certbot, please consider supporting our work by: Donating to ISRG / Let's Encrypt: https://letsencrypt.org/donate Donating to EFF: https://eff.org/donate-le # success if [Congratulations] is shown # certs are created under the [/etc/letsencrypt/live/(FQDN)/] directory # cert.pem ⇒ SSL Server cert(includes public-key) # chain.pem ⇒ intermediate certificate # fullchain.pem ⇒ combined file cert.pem and chain.pem # privkey.pem ⇒ private-key file |
[3] | If no Web Server is running on your working server, it's possbile to get certs with using Certbot's Web Server feature. Anyway, it needs that it's possible to access from the Internet to your working server on port 80 because of verification from Let's Encrypt. |
# for the option [--standalone], use Certbot's Web Server feature # -d [FQDN you'd like to get certs] # FQDN (Fully Qualified Domain Name) : Hostname.Domainname
# if you'd like to get certs for more than 2 FQDNs, specify all like below # ex : if get [srv.world] and [www.srv.world] ⇒ specify [-d srv.world -d www.srv.world]
certbot certonly --standalone -d www.srv.world Saving debug log to /var/log/letsencrypt/letsencrypt.log Plugins selected: Authenticator standalone, Installer None Obtaining a new certificate Performing the following challenges: http-01 challenge for www.srv.world Waiting for verification... Cleaning up challenges IMPORTANT NOTES: - Congratulations! Your certificate and chain have been saved at: /etc/letsencrypt/live/www.srv.world/fullchain.pem Your key file has been saved at: /etc/letsencrypt/live/www.srv.world/privkey.pem Your cert will expire on 2021-07-31. To obtain a new or tweaked version of this certificate in the future, simply run certbot again. To non-interactively renew *all* of your certificates, run "certbot renew" - If you like Certbot, please consider supporting our work by: Donating to ISRG / Let's Encrypt: https://letsencrypt.org/donate Donating to EFF: https://eff.org/donate-le |
[4] | To Update existing certificates manually, Do like follows. |
# update all certs which has less than 30 days expiration # if you'd like to update certs which has more than 30 days expiration, add [--force-renew] option [root@dlp ~]# certbot renew |
[5] | To Update existing certificates automatically, Start services for renewals which are included in Certbot package. |
# Systemd Timer is included [root@dlp ~]# systemctl cat certbot-renew.timer # /usr/lib/systemd/system/certbot-renew.timer [Unit] Description=This is the timer to set the schedule for automated renewals [Timer] OnCalendar=*-*-* 00/12:00:00 RandomizedDelaySec=12hours Persistent=true [Install] WantedBy=timers.target
[root@dlp ~]#
[root@dlp ~]# systemctl enable --now certbot-renew.timer
systemctl list-timers certbot-renew.timer NEXT LEFT LAST PASSED UNIT ACTIVATES Fri 2021-04-29 13:31:20 JST 2h 49min left n/a n/a certbot-renew.timer certbot-renew.service 1 timers listed. Pass --all to see loaded but inactive timers, too. # line 17 : possible to specify pre-commands # An example to stop the MTA before updating certs would be # PRE_HOOK="--pre-hook 'systemctl stop postfix'" PRE_HOOK="" # line 29 : possible to specify post-commands # An example to restart httpd would be: # POST_HOOK="--post-hook 'systemctl restart httpd'" POST_HOOK="" |
[6] | If you'd like to convert certificates to PKCS12 (PFX) format for Windows, do like follows. |
[root@dlp ~]# openssl pkcs12 -export -in fullchain.pem -inkey privkey.pem -out dlp_for_iis.pfx
Enter Export Password: # set any export password
Verifying - Enter Export Password:
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