Certbot error: "Redirect loop detected"

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1

Hello - I am getting a "Redirect loop detected" error when I run the "certbot renew --dry-run" command.

Any ideas on what is causing this error?

Please fill out the fields below so we can help you better. Note: you must provide your domain name to get help. Domain names for issued certificates are all made public in Certificate Transparency logs (e.g. crt.sh | example.com), so withholding your domain name here does not increase secrecy, but only makes it harder for us to provide help.

My domain is: rpiweather.net

I ran this command: sudo certbot renew --dry-run

It produced this output:
Saving debug log to /var/log/letsencrypt/letsencrypt.log

Processing /etc/letsencrypt/renewal/rpiweather.net.conf

Cert not due for renewal, but simulating renewal for dry run
Plugins selected: Authenticator webroot, Installer None
Simulating renewal of an existing certificate for rpiweather.net and www.rpiweather.net
Performing the following challenges:
http-01 challenge for rpiweather.net
http-01 challenge for www.rpiweather.net
Using the webroot path /var/www/rpiweather.net for all unmatched domains.
Waiting for verification...
Challenge failed for domain rpiweather.net
Challenge failed for domain www.rpiweather.net
http-01 challenge for rpiweather.net
http-01 challenge for www.rpiweather.net
Cleaning up challenges
Failed to renew certificate rpiweather.net with error: Some challenges have failed.

All simulated renewals failed. The following certificates could not be renewed:
/etc/letsencrypt/live/rpiweather.net/fullchain.pem (failure)

1 renew failure(s), 0 parse failure(s)

IMPORTANT NOTES:

My web server is (include version): nginx version: nginx/1.18.0

The operating system my web server runs on is (include version):PRETTY_NAME="Raspbian GNU/Linux 11 (bullseye)"
NAME="Raspbian GNU/Linux"
VERSION_ID="11"
VERSION="11 (bullseye)"
VERSION_CODENAME=bullseye
ID=raspbian
ID_LIKE=debian

My hosting provider, if applicable, is: dynu.com

I can login to a root shell on my machine (yes or no, or I don't know): yes

I'm using a control panel to manage my site (no, or provide the name and version of the control panel):

The version of my client is (e.g. output of certbot --version or certbot-auto --version if you're using Certbot): certbot 1.12.0

2

What shows?:

nginx -T

2 Likes
3

I get this using sudo nginx -T:

 sudo nginx -T
nginx: the configuration file /etc/nginx/nginx.conf syntax is ok
nginx: configuration file /etc/nginx/nginx.conf test is successful
# configuration file /etc/nginx/nginx.conf:
user www-data;
worker_processes auto;
pid /run/nginx.pid;
include /etc/nginx/modules-enabled/*.conf;

events {
        worker_connections 768;
        # multi_accept on;
}

http {

        ##
        # Basic Settings
        ##

        sendfile on;
        tcp_nopush on;
        types_hash_max_size 2048;
        # server_tokens off;

        # server_names_hash_bucket_size 64;
        # server_name_in_redirect off;

        include /etc/nginx/mime.types;
        default_type application/octet-stream;

        ##
        # SSL Settings
        ##

        ssl_protocols TLSv1 TLSv1.1 TLSv1.2 TLSv1.3; # Dropping SSLv3, ref: POODLE
        ssl_prefer_server_ciphers on;

        ##
        # Logging Settings
        ##

        access_log /var/log/nginx/access.log;
        error_log /var/log/nginx/error.log;

        ##
        # Gzip Settings
        ##

        gzip on;

        # gzip_vary on;
        # gzip_proxied any;
        # gzip_comp_level 6;
        # gzip_buffers 16 8k;
        # gzip_http_version 1.1;
        # gzip_types text/plain text/css application/json application/javascript text/xml application/xml application/xml+rss text/javascript;

        ##
        # Virtual Host Configs
        ##

        include /etc/nginx/conf.d/*.conf;
        include /etc/nginx/sites-enabled/*;
}


#mail {
#       # See sample authentication script at:
#       # http://wiki.nginx.org/ImapAuthenticateWithApachePhpScript
#
#       # auth_http localhost/auth.php;
#       # pop3_capabilities "TOP" "USER";
#       # imap_capabilities "IMAP4rev1" "UIDPLUS";
#
#       server {
#               listen     localhost:110;
#               protocol   pop3;
#               proxy      on;
#       }
#
#       server {
#               listen     localhost:143;
#               protocol   imap;
#               proxy      on;
#       }
#}

# configuration file /etc/nginx/modules-enabled/50-mod-http-geoip.conf:
load_module modules/ngx_http_geoip_module.so;

# configuration file /etc/nginx/modules-enabled/50-mod-http-image-filter.conf:
load_module modules/ngx_http_image_filter_module.so;

# configuration file /etc/nginx/modules-enabled/50-mod-http-xslt-filter.conf:
load_module modules/ngx_http_xslt_filter_module.so;

# configuration file /etc/nginx/modules-enabled/50-mod-mail.conf:
load_module modules/ngx_mail_module.so;

# configuration file /etc/nginx/modules-enabled/50-mod-stream.conf:
load_module modules/ngx_stream_module.so;

# configuration file /etc/nginx/modules-enabled/70-mod-stream-geoip.conf:
load_module modules/ngx_stream_geoip_module.so;

# configuration file /etc/nginx/mime.types:

types {
    text/html                             html htm shtml;
    text/css                              css;
    text/xml                              xml;
    image/gif                             gif;
    image/jpeg                            jpeg jpg;
    application/javascript                js;
    application/atom+xml                  atom;
    application/rss+xml                   rss;

    text/mathml                           mml;
    text/plain                            txt;
    text/vnd.sun.j2me.app-descriptor      jad;
    text/vnd.wap.wml                      wml;
    text/x-component                      htc;

    image/png                             png;
    image/tiff                            tif tiff;
    image/vnd.wap.wbmp                    wbmp;
    image/x-icon                          ico;
    image/x-jng                           jng;
    image/x-ms-bmp                        bmp;
    image/svg+xml                         svg svgz;
    image/webp                            webp;

    application/font-woff                 woff;
    application/java-archive              jar war ear;
    application/json                      json;
    application/mac-binhex40              hqx;
    application/msword                    doc;
    application/pdf                       pdf;
    application/postscript                ps eps ai;
    application/rtf                       rtf;
    application/vnd.apple.mpegurl         m3u8;
    application/vnd.ms-excel              xls;
    application/vnd.ms-fontobject         eot;
    application/vnd.ms-powerpoint         ppt;
    application/vnd.wap.wmlc              wmlc;
    application/vnd.google-earth.kml+xml  kml;
    application/vnd.google-earth.kmz      kmz;
    application/x-7z-compressed           7z;
    application/x-cocoa                   cco;
    application/x-java-archive-diff       jardiff;
    application/x-java-jnlp-file          jnlp;
    application/x-makeself                run;
    application/x-perl                    pl pm;
    application/x-pilot                   prc pdb;
    application/x-rar-compressed          rar;
    application/x-redhat-package-manager  rpm;
    application/x-sea                     sea;
    application/x-shockwave-flash         swf;
    application/x-stuffit                 sit;
    application/x-tcl                     tcl tk;
    application/x-x509-ca-cert            der pem crt;
    application/x-xpinstall               xpi;
    application/xhtml+xml                 xhtml;
    application/xspf+xml                  xspf;
    application/zip                       zip;

    application/octet-stream              bin exe dll;
    application/octet-stream              deb;
    application/octet-stream              dmg;
    application/octet-stream              iso img;
    application/octet-stream              msi msp msm;

    application/vnd.openxmlformats-officedocument.wordprocessingml.document    docx;
    application/vnd.openxmlformats-officedocument.spreadsheetml.sheet          xlsx;
    application/vnd.openxmlformats-officedocument.presentationml.presentation  pptx;

    audio/midi                            mid midi kar;
    audio/mpeg                            mp3;
    audio/ogg                             ogg;
    audio/x-m4a                           m4a;
    audio/x-realaudio                     ra;

    video/3gpp                            3gpp 3gp;
    video/mp2t                            ts;
    video/mp4                             mp4;
    video/mpeg                            mpeg mpg;
    video/quicktime                       mov;
    video/webm                            webm;
    video/x-flv                           flv;
    video/x-m4v                           m4v;
    video/x-mng                           mng;
    video/x-ms-asf                        asx asf;
    video/x-ms-wmv                        wmv;
    video/x-msvideo                       avi;
}

# configuration file /etc/nginx/sites-enabled/default:
##
# You should look at the following URL's in order to grasp a solid understanding
# of Nginx configuration files in order to fully unleash the power of Nginx.
# https://www.nginx.com/resources/wiki/start/
# https://www.nginx.com/resources/wiki/start/topics/tutorials/config_pitfalls/
# https://wiki.debian.org/Nginx/DirectoryStructure
#
# In most cases, administrators will remove this file from sites-enabled/ and
# leave it as reference inside of sites-available where it will continue to be
# updated by the nginx packaging team.
#
# This file will automatically load configuration files provided by other
# applications, such as Drupal or Wordpress. These applications will be made
# available underneath a path with that package name, such as /drupal8.
#
# Please see /usr/share/doc/nginx-doc/examples/ for more detailed examples.
##

# Default server configuration
#
server {
        listen 80 default_server;
        listen [::]:80 default_server;

        # SSL configuration
        #
        # listen 443 ssl default_server;
        # listen [::]:443 ssl default_server;
        #
        # Note: You should disable gzip for SSL traffic.
        # See: https://bugs.debian.org/773332
        #
        # Read up on ssl_ciphers to ensure a secure configuration.
        # See: https://bugs.debian.org/765782
        #
        # Self signed certs generated by the ssl-cert package
        # Don't use them in a production server!
        #
        # include snippets/snakeoil.conf;

        root /var/www/html;

        # Add index.php to the list if you are using PHP
        index index.html index.htm index.nginx-debian.html;

        server_name _;

        location / {
                # First attempt to serve request as file, then
                # as directory, then fall back to displaying a 404.
                try_files $uri $uri/ =404;
        }

        # pass PHP scripts to FastCGI server
        #
        #location ~ \.php$ {
        #       include snippets/fastcgi-php.conf;
        #
        #       # With php-fpm (or other unix sockets):
        #       fastcgi_pass unix:/run/php/php7.4-fpm.sock;
        #       # With php-cgi (or other tcp sockets):
        #       fastcgi_pass 127.0.0.1:9000;
        #}

        # deny access to .htaccess files, if Apache's document root
        # concurs with nginx's one
        #
        #location ~ /\.ht {
        #       deny all;
        #}
}


# Virtual Host configuration for example.com
#
# You can move that to a different file under sites-available/ and symlink that
# to sites-enabled/ to enable it.
#
#server {
#       listen 80;
#       listen [::]:80;
#
#       server_name example.com;
#
#       root /var/www/example.com;
#       index index.html;
#
#       location / {
#               try_files $uri $uri/ =404;
#       }
#}

# configuration file /etc/nginx/sites-enabled/rpiweather.net:
server {
       listen 80;
       listen [::]:80;

       server_name rpiweather.net www.rpiweather.net;

       root /var/www/rpiweather.net;
       index index.html;

       listen 443 ssl; # managed by Certbot

       # RSA certificate
       ssl_certificate /etc/letsencrypt/live/rpiweather.net/fullchain.pem; # managed by Certbot
       ssl_certificate_key /etc/letsencrypt/live/rpiweather.net/privkey.pem; # managed by Certbot

       #include /etc/letsencrypt/options-ssl-nginx.conf; # managed by Certbot

       # Redirect non-https traffic to https
       if ($scheme != "https") {
           return 301 https://$host$request_uri;
       } # managed by Certbot

       location / {
               try_files $uri $uri/ =404;
       }
}
5

Ignore my previous deleted post.

I didn't notice the "Certbot error" in your title.

It is probably just seeing a redirect to https inside a server block that is listening on port 443. That normally is a problem.

But, in your case you limit the redirect with an IF statement and checking $scheme

A better solution is to make a dedicated server block that listens only on port 80 for that domain name. And, just do a redirect to https in that.

In your current server block that listens on both 80 and 443 then remove the two listens for port 80. That leaves you with a dedicated server block for HTTP and a dedicated one for HTTPS

Also, you should be consistent in your listens for IPv4 and IPv6. You listen for both on port 80 but only IPv4 for port 443.

3 Likes
6

In short: Split this single vhost in two [one for only :80 and another for only :443]

server {
       listen 80;
       listen [::]:80;
       server_name rpiweather.net www.rpiweather.net;
       listen 443 ssl; # managed by Certbot
}

[and don't forget to also listen on "[::]:443"]

2 Likes
7

So my rpiweather.net should look like this?

server {
       listen 80;
       listen [::]:80;
       server_name rpiweather.net www.rpiweather.net;
       listen 443 ssl; # managed by Certbot
}

server {
       listen 443;
       listen [::]:443;

       server_name rpiweather.net www.rpiweather.net;

       root /var/www/rpiweather.net;
       index index.html;

       listen 443 ssl; # managed by Certbot

       # RSA certificate
       ssl_certificate /etc/letsencrypt/live/rpiweather.net/fullchain.pem; # managed by Certbot
       ssl_certificate_key /etc/letsencrypt/live/rpiweather.net/privkey.pem; # managed by Certbot

       #include /etc/letsencrypt/options-ssl-nginx.conf; # managed by Certbot

       # Redirect non-https traffic to https
       if ($scheme != "https") {
           return 301 https://$host$request_uri;
       } # managed by Certbot

       location / {
               try_files $uri $uri/ =404;
       }
}
8

No. The listen statements should look like below. I also added items in your HTTP server block to handle the --webroot method you are now using. It looks like you made significant changes to your nginx config after getting the original cert for your certbot renew to now fail like it does.

server {
       listen 80;
       listen [::]:80;
       server_name rpiweather.net www.rpiweather.net;

       # ACME Challenges use this root folder (from your old https server block)
       location /.well-known/acme-challenge/ {
         root /var/www/rpiweather.net;
       }

       # All other requests get redirected to https
       location / {
          return 301 https://$host$request_uri;
       }
}

server {
       listen 443 ssl;
       listen [::]:443 ssl;

       server_name rpiweather.net www.rpiweather.net;

       root /var/www/rpiweather.net;
       index index.html;

       # RSA certificate
       ssl_certificate /etc/letsencrypt/live/rpiweather.net/fullchain.pem; # managed by Certbot
       ssl_certificate_key /etc/letsencrypt/live/rpiweather.net/privkey.pem; # managed by Certbot

       #include /etc/letsencrypt/options-ssl-nginx.conf; # managed by Certbot

       location / {
               try_files $uri $uri/ =404;
       }
}

Also, why do you even have this line? Your certbot renew did not use the --nginx plugin installer so you would never have gotten this file. And, Certbot never would have placed this line in your nginx config.

Do you have ssl options configured somewhere else? Such as ssl_ciphers, ssl_protocols, and so on?

       #include /etc/letsencrypt/options-ssl-nginx.conf; # managed by Certbot
3 Likes
9

That change seems to have worked, thank you!

I got this:

pi@HomeAutomation:~ $ sudo certbot renew --dry-run
Saving debug log to /var/log/letsencrypt/letsencrypt.log

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Processing /etc/letsencrypt/renewal/rpiweather.net.conf
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Cert not due for renewal, but simulating renewal for dry run
Plugins selected: Authenticator webroot, Installer None
Simulating renewal of an existing certificate for rpiweather.net and www.rpiweat                                                                                                                    her.net
Performing the following challenges:
http-01 challenge for rpiweather.net
http-01 challenge for www.rpiweather.net
Using the webroot path /var/www/rpiweather.net for all unmatched domains.
Waiting for verification...
Cleaning up challenges

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
new certificate deployed without reload, fullchain is
/etc/letsencrypt/live/rpiweather.net/fullchain.pem
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Congratulations, all simulated renewals succeeded:
  /etc/letsencrypt/live/rpiweather.net/fullchain.pem (success)
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

Not sure how things got bunged up, but it must have been the result of the new system installation after the SD card in my Raspberry Pi failed. I built the new system using the latest OS version but I probably copied some of the config files off the backup of the old system.

Thank you for the help!

2 Likes
10

Sure, you are welcome.

The options you chose do not automatically reload nginx after you get a fresh cert.

You can either use your own cronjob to regularly reload nginx (maybe daily) to do that. Or, you can add a deploy-hook to your Certbot cert renewal profile to do it.

You should be able to setup your own cronjob. But, if you want help with the deploy-hook let us know

2 Likes
11

I think the renewal is being handled by systemctl:

pi@HomeAutomation:~ $ sudo systemctl status certbot.timer -l
● certbot.timer - Run certbot twice daily
     Loaded: loaded (/lib/systemd/system/certbot.timer; enabled; vendor preset: enabled)
     Active: active (waiting) since Sat 2024-04-13 07:44:37 EDT; 6h ago
    Trigger: Sat 2024-04-13 20:14:56 EDT; 5h 56min left
   Triggers: ● certbot.service

Apr 13 07:44:37 HomeAutomation systemd[1]: Started Run certbot twice daily.
pi@HomeAutomation:~ $

Does this automatically reload the nginx?

I also use crontab to reboot the Raspberry Pi each day at 2:01 AM. I find this daily reboot to keep things ticking nicely.

1 Like
12

Not sure. You should check the renewal logs or /etc/letsencrypt/renewal (please don't edit that stuff manually)

2 Likes
13

That depends on what is in the Certbot renewal profile. If you setup a --deploy-hook to reload nginx then yes. Otherwise no.

That certainly reloads nginx ! :slight_smile: So, you are fine.

2 Likes