Hello
First lets start with this.
You can find more here and it should give you a better insight.
https://docs.graylog.org/v1/docs/sec-adcs-certificates
That is where the subjectAltName comes in. Have you tried to configure your /etc/hosts file?
127.0.0.1 localhost localhost.localdomain localhost4 localhost4.localdomain4
::1 localhost localhost.localdomain localhost6 localhost6.localdomain6
192.168.1.12 graylog.domain.com
Basic steps with Graylog are that it has to be in the right format and a the certificates that are used should be in your keystore while graylog has access to them. If the error shows
The hostname is not verified clues me in that something is either wrong with the certificates OR Graylog Cant access them. If its the format of the certificate then the link above should guide you to fix that.
If Graylog is unable to verified the hostname, I gave a couple of checks shown above hoping it would help you troubleshoot your issue but I don’t know if you did it. Even thou your able to use those certificate in other devices they may not work on Graylog UNLESS you satisfy the requirements stated in the documents.
Here is a few examples of a community members having the same problem.
Next
If you’re using a CA that’s known (e.g., Letsencrypt, etc.), then you can add the following attributes to your server config. Remember format and permissions but even if you use those for your input Graylog has to be able to find them meaning they should be in the right format in your keystore.
These would be the setting shown below
http_enable_tls=true
http_tls_cert_file=/etc/graylog/ssl/fullchain.pem
http_tls_key_file=/etc/graylog/ssl/privkey.pem
http_publish_uri=https://logs00.example.com:9000/
And as long as your CA is part of the systems certificate store, it should work.
Can I ask what have you tried to resolve this issue besides googling? Because this issue could be a couple things that may need to be reconfigured, so in other words trying and reposting what you have done would help us narrow it down.
hope that helps