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. https://crt.sh/?q=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:
www. kinetix.digital
I ran this command:
sudo certbot --nginx -d kinetix.digital -d www.kinetix.digital
It produced this output:
Certbot failed to authenticate some domains (authenticator: nginx). The Certificate Authority reported these problems:
Domain: kinetix.digital
Type: dns
Detail: no valid A records found for kinetix.digital; no valid AAAA records found for kinetix.digital
Domain: www.kinetix.digital
Type: dns
Detail: DNS problem: NXDOMAIN looking up A for www.kinetix.digital - check that a DNS record exists for this domain; DNS problem: NXDOMAIN looking up AAAA for www.kinetix.digital - check that a DNS record exists for this domain
Hint: The Certificate Authority failed to verify the temporary nginx configuration changes made by Certbot. Ensure the listed domains point to this nginx server and that it is accessible from the internet.
The operating system my web server runs on is (include version): ubuntu
My hosting provider, if applicable, is: Namecheap
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):
no
The version of my client is (e.g. output of certbot --version or certbot-auto --version if you're using Certbot):certbot 1.21.0
I have added an A record pointing to my ip i have alose run nslookup and it comes up ok, but stil getting the certbot error saying no vaid A records found.
Yes you added an A record but it is a private IP. For the HTTP challenge it must be a public IP. And if you want anyone on the public Internet to reach it it will also need to be a public IP
OK, sorry new to this. I need to add a cert with certbot as I am using Nginx with Jenkins on a VM with Ubuntu. At the moment Niginx and Jenkins is installed. I have completed all the nginx with config block and linked to the sites-enabled directory. So now in Jenkins all works but its not secure so I need to add the cert so I can use https. Hope that is clear
You need a working HTTP service before trying to secure it.
Also, HTTP must be accessible from the Internet [not just some parts of it]; As ACME validation requests may come from anywhere on the Internet.
That's probably because it currently has a NameCheap IP address set up. So I'm not sure what OP did previously with the LAN IP address, but apparently they are hosting their website with NameCheap now and not locally.
You need to understand how Certbot, and ACME in general works.
Please read How It Works - Let's Encrypt first, get a good grasp on how ACME works, then understand what you've done with your NameCheap domain (we don't) and then ask again for help with directed questions (and explain what you've done with NameCheap).
Oh and in general, what you're trying to achieve to begin with.