Jitsi meet Server Ubuntu 18.04 fails at SSL certification step

Hello

By following the steps for install jitsi-meet on server, the procedures runs OK up to the videobridge command

sudo apt install jitsi-meet -y

there were few errors at this step.

nginx.service is not active, cannot reload.
invoke-rc.d: initscript nginx, action “reload” failed.
dpkg: error processing package jitsi-meet-web-config (–configure):
installed jitsi-meet-web-config package post-installation script subprocess returned error exit status 1

at the end, after the security command

/usr/share/jitsi-meet/scripts/install-letsencrypt-cert.sh

the following step triggers a warning

Waiting for verification…
Challenge failed for domain mydomain.com

IMPORTANT NOTES:

  • The following errors were reported by the server:

    Domain: mydomain .
    Type: unauthorized
    Detail: Invalid response from
    http://antalari.cl/.well-known/acme-challenge/KuzBSi3Zglp72CE6AjxhqLQlJ4s_676i5RU6sgrbp-w
    [186.64.117.225]: “\n\n404 Not
    Found\n\n

    Not Found

    \n<p”

    To fix these errors, please make sure that your domain name was
    entered correctly and the DNS A/AAAA record(s) for that domain
    contain(s) the right IP address.

  • 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.

I have seen some threads regarding this kind of error but they pointed to other SSL steps. it is possible to install self-signed certificates? it is required to repeat the process until the certificates screen and browse for them over the machine ?

many thanks