Letsencrypt renewal fails: Could not bind to IPv4 or IPv6.. Skipping

As hinted in the other answers, you need to pass the option for your running webserver, for example:

Without webserver param:

sudo certbot renew

Cert is due for renewal, auto-renewing...
Renewing an existing certificate
Performing the following challenges:tls-sni-01 challenge for example.com
Cleaning up challenges Attempting to renew cert (example.com) from /etc/letsencrypt/renewal/example.com.conf produced an unexpected error:
Problem binding to port 443: Could not bind to IPv4 or IPv6.. Skipping.

Then, again with the webserver param (success):

sudo certbot renew --nginx 

Cert is due for renewal, auto-renewing...
Renewing an existing certificate
Performing the following challenges: tls-sni-01 challenge for example.com
Waiting for verification...
Cleaning up challenges

new certificate deployed with reload of nginx server; fullchain is /etc/letsencrypt/live/example.com/fullchain.pem

Congratulations, all renewals succeeded. The following certs have been renewed: /etc/letsencrypt/live/example.com/fullchain.pem (success)

[This is specifically for ubuntu]

1. Login as root user to your server

2. Stop your server using the following command (for nginx)

   service nginx stop

3. Then renew your certificate

   certbot renew

4. Start your server

   service nginx start

[TIP] To check the expiry date of your renewed certificate, enter the command below

ssl-cert-check -c [Path_to_your_certificate]/fullchain.pem

For example

ssl-cert-check -c /etc/letsencrypt/live/[your_domain_name]/fullchain.pem

Or

ssl-cert-check -c /etc/letsencrypt/live/[your_domain_name]/cert.pem

If you don't have ssl-cert-check already installed in your server, install it using

apt install ssl-cert-check

Note: The certificate can be renewed only if it is not expired. If it is expired, you have to create new one.

For NodeJS/PM2 users

I was using PM2 for my NodeJS service and when trying to renew the certificate I also got the "Problem binding to port 80: Could not bind to IPv4 or IPv6." error message.

As mentioned in above answers for Apache/Ngnix, Stopping my service and then trying to renew solved the problem.

pm2 stop all
sudo certbot renew
pm2 start all

First you need to install NGiNX lets encrypt plugin (if you work with NGiNX):

sudo apt install python-certbot-nginx

Then you can safely run:

sudo certbot renew --nginx

and it will work.

Note: certbot should already be installed.

Borrowing from @JKLIR Simply run

/etc/letsencrypt/letsencrypt-auto renew --apache >> /var/log/letsencrypt/renew.log

to renew the ssl certificate

For ngnix

sudo certbot renew --nginx

If you're trying to perform the certbot command as a regular user, you may not have access to bind to port 80 and other lower ports. If this is the case, you can grant python access to bind via:

1. First, see if you can find python 3+ (adjust as needed)

   echo "$(readlink -f "$(which python3)")"
   

2. Allow python to open port 80 as a regular user (adjust as needed)

   sudo setcap CAP_NET_BIND_SERVICE=+eip "$(readlink -f "$(which python3)")"
   

3. Re-run the failing certbot command.

Important: On Ubuntu 18.04, Python is called python3. It may be called a number of different things depending on the OS and how you obtained certbot. This command WILL VARY between OSs.

Warning: These lower ports are restricted for good reason. There are security considerations with the setcap command. You may read more about them here: https://superuser.com/a/892391

I use Nginx and needed to stop the server before I can proceed. Then I run the command:

$ sudo ./certbot-auto  certonly --standalone -d chaklader.ddns.net
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 chaklader.ddns.net
Waiting for verification...
Cleaning up challenges
Subscribe to the EFF mailing list (email: xxx.chakfffder@gmail.com).

IMPORTANT NOTES:
 - Congratulations! Your certificate and chain have been saved at:
   /etc/letsencrypt/live/cdddddder.ddns.net/fullchain.pem
   Your key file has been saved at:
   /etc/letsencrypt/live/chaklader.ddns.net/privkey.pem
   Your cert will expire on 2045-01-10. To obtain a new or tweaked
   version of this certificate in the future, simply run certbot-auto
   again. To non-interactively renew *all* of your certificates, run
   "certbot-auto 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

I had a similar issue when I was running two websites (hosts) on a single instance. I stopped Nginx and then ran sudo certbot certonly --standalone --preferred-challenges http -d domain.com -d www.domain.com. After restarting Nginx everything started to work fine.