====== Download a Server Certificate ======

First, load the certificate chain from the server:

<code bash>
openssl s_client -showcerts -connect www.example.org:443 </dev/null
</code>

This will output the whole server certificate chain.
Every chertificate ist wrapped between ''-----BEGIN CERTIFICATE-----'' and ''-----END CERTIFICATE-----''.
The first certificate is the server certificate.
So you only need to copy the output from the first ''-----BEGIN CERTIFICATE-----'' to the first ''-----END CERTIFICATE-----'' to a file.
This certificate is in the PEM (text) format.
To convert it to the binary DER format see [[convert_certificate]].

{{tag>openssl security cryptography certificate howto}}