Error

How are you hosting your site?

Thanks @sterndata . I am using Localhost. Thanks.

You may be blocking outbound connections via https or your are lacking the proper security certificates on your server.

What do you see for this command?

$ curl -v https://api.www.ads-software.com

I get

*   Trying 198.143.164.251:443...
* Connected to api.www.ads-software.com (198.143.164.251) port 443 (#0)
* ALPN, offering h2
* ALPN, offering http/1.1
* successfully set certificate verify locations:
*  CAfile: /etc/pki/tls/certs/ca-bundle.crt
*  CApath: none
* TLSv1.3 (OUT), TLS handshake, Client hello (1):
* TLSv1.3 (IN), TLS handshake, Server hello (2):
* TLSv1.3 (IN), TLS handshake, Encrypted Extensions (8):
* TLSv1.3 (IN), TLS handshake, Certificate (11):
* TLSv1.3 (IN), TLS handshake, CERT verify (15):
* TLSv1.3 (IN), TLS handshake, Finished (20):
* TLSv1.3 (OUT), TLS change cipher, Change cipher spec (1):
* TLSv1.3 (OUT), TLS handshake, Finished (20):
* SSL connection using TLSv1.3 / TLS_AES_256_GCM_SHA384
* ALPN, server accepted to use h2
* Server certificate:
*  subject: CN=*.www.ads-software.com
*  start date: Nov 22 00:00:00 2020 GMT
*  expire date: Dec 23 23:59:59 2021 GMT
*  subjectAltName: host "api.www.ads-software.com" matched cert's "*.www.ads-software.com"
*  issuer: C=GB; ST=Greater Manchester; L=Salford; O=Sectigo Limited; CN=Sectigo RSA Domain Validation Secure Server CA
*  SSL certificate verify ok.
* Using HTTP2, server supports multi-use
* Connection state changed (HTTP/2 confirmed)
* Copying HTTP/2 data in stream buffer to connection buffer after upgrade: len=0
* Using Stream ID: 1 (easy handle 0x55a76c6eeaf0)
> GET / HTTP/2
> Host: api.www.ads-software.com
> user-agent: curl/7.76.1
> accept: */*
> 
* TLSv1.3 (IN), TLS handshake, Newsession Ticket (4):
* TLSv1.3 (IN), TLS handshake, Newsession Ticket (4):
* old SSL session ID is stale, removing
* Connection state changed (MAX_CONCURRENT_STREAMS == 128)!
< HTTP/2 302 
< server: nginx
< date: Mon, 21 Jun 2021 14:00:34 GMT
< content-type: text/html; charset=utf-8
< location: https://developer.www.ads-software.com/rest-api/
< x-frame-options: SAMEORIGIN
< 
* Connection #0 to host api.www.ads-software.com left intact

Thanks @sterndata. Here is my result.

foysal@laptop:~$ curl -v https://api.www.ads-software.com
* Rebuilt URL to: https://api.www.ads-software.com/
*   Trying 198.143.164.251...
* TCP_NODELAY set
* Connected to api.www.ads-software.com (198.143.164.251) port 443 (#0)
* ALPN, offering h2
* ALPN, offering http/1.1
* successfully set certificate verify locations:
*   CAfile: /etc/ssl/certs/ca-certificates.crt
  CApath: /etc/ssl/certs
* TLSv1.3 (OUT), TLS handshake, Client hello (1):
* TLSv1.3 (IN), TLS handshake, Server hello (2):
* TLSv1.3 (IN), TLS Unknown, Certificate Status (22):
* TLSv1.3 (IN), TLS handshake, Unknown (8):
* TLSv1.3 (IN), TLS Unknown, Certificate Status (22):
* TLSv1.3 (IN), TLS handshake, Certificate (11):
* TLSv1.3 (IN), TLS Unknown, Certificate Status (22):
* TLSv1.3 (IN), TLS handshake, CERT verify (15):
* TLSv1.3 (IN), TLS Unknown, Certificate Status (22):
* TLSv1.3 (IN), TLS handshake, Finished (20):
* TLSv1.3 (OUT), TLS change cipher, Client hello (1):
* TLSv1.3 (OUT), TLS Unknown, Certificate Status (22):
* TLSv1.3 (OUT), TLS handshake, Finished (20):
* SSL connection using TLSv1.3 / TLS_AES_256_GCM_SHA384
* ALPN, server accepted to use h2
* Server certificate:
*  subject: CN=*.www.ads-software.com
*  start date: Nov 22 00:00:00 2020 GMT
*  expire date: Dec 23 23:59:59 2021 GMT
*  subjectAltName: host "api.www.ads-software.com" matched cert's "*.www.ads-software.com"
*  issuer: C=GB; ST=Greater Manchester; L=Salford; O=Sectigo Limited; CN=Sectigo RSA Domain Validation Secure Server CA
*  SSL certificate verify ok.
* Using HTTP2, server supports multi-use
* Connection state changed (HTTP/2 confirmed)
* Copying HTTP/2 data in stream buffer to connection buffer after upgrade: len=0
* TLSv1.3 (OUT), TLS Unknown, Unknown (23):
* TLSv1.3 (OUT), TLS Unknown, Unknown (23):
* TLSv1.3 (OUT), TLS Unknown, Unknown (23):
* Using Stream ID: 1 (easy handle 0x55a6579d57d0)
* TLSv1.3 (OUT), TLS Unknown, Unknown (23):
> GET / HTTP/2
> Host: api.www.ads-software.com
> User-Agent: curl/7.58.0
> Accept: */*
> 
* TLSv1.3 (IN), TLS Unknown, Certificate Status (22):
* TLSv1.3 (IN), TLS handshake, Newsession Ticket (4):
* TLSv1.3 (IN), TLS Unknown, Certificate Status (22):
* TLSv1.3 (IN), TLS handshake, Newsession Ticket (4):
* TLSv1.3 (IN), TLS Unknown, Unknown (23):
* Connection state changed (MAX_CONCURRENT_STREAMS updated)!
* TLSv1.3 (OUT), TLS Unknown, Unknown (23):
* TLSv1.3 (IN), TLS Unknown, Unknown (23):
* TLSv1.3 (IN), TLS Unknown, Unknown (23):
< HTTP/2 302 
< server: nginx
< date: Mon, 21 Jun 2021 15:38:03 GMT
< content-type: text/html; charset=utf-8
< location: https://developer.www.ads-software.com/rest-api/
< x-frame-options: SAMEORIGIN
< 
* Connection #0 to host api.www.ads-software.com left intact
foysal@laptop:~$ 

So you can connect from the command line. This means something in your web stack is blocking connecting from the web server. SELinux, perhaps?

Check your server logs as well as /var/log/messages.

• This reply was modified 3 years, 5 months ago by Steven Stern (sterndata).

Thanks @sterndata . I am using Linux Mint 19.1 as OS.

Does Mint include SELinrx?

Thanks @sterndata . No. Thanks.