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:
caoyx.cyxhj.buzz
I ran this command:
sudo certbot certonly --standalone
It produced this output:
root@vultr:~# sudo certbot certonly --standalone
Saving debug log to /var/log/letsencrypt/letsencrypt.log
Plugins selected: Authenticator standalone, Installer None
Please enter in your domain name(s) (comma and/or space separated) (Enter 'c'
to cancel): caoyx.cyxhj.buzz
Obtaining a new certificate
Performing the following challenges:
http-01 challenge for caoyx.cyxhj.buzz
Waiting for verification...
Cleaning up challenges
Failed authorization procedure. caoyx.cyxhj.buzz (http-01): urn:ietf:params:acme:error:connection :: The server could not connect to the client to verify the domain :: 158.247.199.7: Fetching http://caoyx.cyxhj.buzz/.well-known/acme-challenge/oqA-qUTVR3UE2EJktc0fgVl2vIV-_ZBx9V1m-Oyq0eU: Timeout during connect (likely firewall problem)
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. Additionally, please check that
your computer has a publicly routable IP address and that no
firewalls are preventing the server from communicating with the
client. If you're using the webroot plugin, you should also verify
that you are serving files from the webroot path you provided.
My web server is (include version):
standalone mode
The operating system my web server runs on is (include version):
Ubuntu 18.04 LTS x64
My hosting provider, if applicable, is: vultr
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):
For me the website access reports "No route to host":
pi@raspberrypi:~ $ curl -s -v 'http://caoyx.cyxhj.buzz/' > /dev/null
...
* Trying 158.247.199.7...
* TCP_NODELAY set
* Expire in 200 ms for 4 (transfer 0x5b5950)
* connect to 158.247.199.7 port 80 failed: No route to host
* Failed to connect to caoyx.cyxhj.buzz port 80: No route to host
* Closing connection 0
pi@raspberrypi:~ $
The program traceroute reports similar thing:
tumbleweed:~ # traceroute -T -p 80 caoyx.cyxhj.buzz
traceroute to caoyx.cyxhj.buzz (158.247.199.7), 30 hops max, 60 byte packets
...
7 ntt-5.gw.opentransit.net (193.251.247.156) 18.613 ms 17.235 ms 17.833 ms
8 ae-3.r20.frnkge13.de.bb.gin.ntt.net (129.250.6.33) 18.551 ms 17.745 ms 17.777 ms
9 * ae-14.r21.londen12.uk.bb.gin.ntt.net (129.250.3.12) 23.491 ms ae-12.r21.parsfr04.fr.bb.gin.ntt.net (129.250.5.27) 19.677 ms
10 ae-13.r24.asbnva02.us.bb.gin.ntt.net (129.250.6.6) 99.959 ms 110.501 ms 95.619 ms
11 ae-2.r25.lsanca07.us.bb.gin.ntt.net (129.250.3.189) 154.162 ms 153.491 ms ae-2.r24.snjsca04.us.bb.gin.ntt.net (129.250.6.237) 153.692 ms
12 ae-5.r26.osakjp02.jp.bb.gin.ntt.net (129.250.2.119) 536.078 ms 251.591 ms ae-1.r24.lsanca07.us.bb.gin.ntt.net (129.250.3.218) 154.853 ms
13 ae-0.r27.osakjp02.jp.bb.gin.ntt.net (129.250.3.45) 262.879 ms ae-5.r27.osakjp02.jp.bb.gin.ntt.net (129.250.2.177) 246.805 ms 259.705 ms
14 ae-3.r00.seolko02.kr.bb.gin.ntt.net (129.250.5.74) 296.946 ms 288.752 ms 297.068 ms
15 xe-0-2-0-1-3.r00.seolko02.kr.ce.gin.ntt.net (61.251.96.90) 285.106 ms 289.780 ms 299.456 ms
16 158.247.199.7.vultrusercontent.com (158.247.199.7) 303.103 ms !X 305.498 ms !X 307.991 ms !X
tumbleweed:~ #
Please note the ICMP reply type !X on the last line of the traceroute. It means "communication administratively prohibited".
@IanCao I can connect to your domain using HTTPS just fine (link here). It looks like you fixed your problem. Do you need any more help?
I see you don't have port 80 (http) open. That works ok if you plan to use --standalone for cert renewal. But, the recommended approach is to keep port 80 open so visitors to your site using HTTP can be redirected to HTTPS. See below topic
Note though that if you start using nginx to handle port 80 you will need to stop using --standalone and instead use --webroot or maybe --nginx authentication.
$ nmap -Pn caoyx.cyxhj.buzz
Starting Nmap 7.80 ( https://nmap.org ) at 2023-02-11 17:41 UTC
Nmap scan report for caoyx.cyxhj.buzz (158.247.199.7)
Host is up (0.19s latency).
rDNS record for 158.247.199.7: 158.247.199.7.vultrusercontent.com
Not shown: 993 closed ports
PORT STATE SERVICE
22/tcp open ssh
25/tcp filtered smtp
135/tcp filtered msrpc
139/tcp filtered netbios-ssn
443/tcp open https
445/tcp filtered microsoft-ds
9999/tcp open abyss
Nmap done: 1 IP address (1 host up) scanned in 19.14 seconds