As an engineer, administrator, operator, or developer, sometimes you need to learn certificate information from an application, host system, or whatever else. Almost all modern browsers allow you to get certificate information by simply clicking a red/green or crossed lock icon or following page information agents. But sometimes you can't use browsers, and you can't leave your CLI session due to a lack of connection problem or other factors. You can use the OpenSSL CLI tool to get basic certificate information on Linux. Openssl is a handy tool that allows you to save a bunch of certificate-based requirements, including getting certificates, renewing, generating a new one and of course getting information from them. In this article, you simply get the certificate information from a saved certificate. [ozgurkkisa@workstation]$ openssl x509 -in \ wildcard-api.pem -noout -subject -issuer -ext 'subjectAltName' -dates subject=C = US, ST = NC, L = Raleigh, O = "Red Ha...
Notes of a technology enthusiast