How to list all available SSL CA certificates on CentOS 6?

//, use opensslcommand to get output from it/etc/ssl/certs/ca-bundle.crt

Anyway, I tried the following, mostly copied from https://unix.stackexchange.com/a/97249/48498 , and it seems to work if I change the filename to CentOS 6:

If you don't want to bother with that flag or similar on --insecurecURL, , wgetGit, etc , you can add a CA root certificate, self-signed certificate or certificate chain to your truststore like this:

1. Follow the instructions to download .crt, .pemor .cerof your choice.

2. Obtain the certificate you want to trust by using any mechanism, usually downloading the certificate from a central repository openssl s_client -showcerts -connect some.host.that.uses.that.root:443, or extracting the certificate from the SSL handshake using or similar , and copying it to the following folder on the target CentOS 6 host :

    /etc/pki/ca-trust/source/anchors/

While logged in to the target host, run the following command:

    $ sudo update-ca-trust enable; sudo update-ca-trust extract

Verify the result on Red Hat based OS , for example:

    $ awk -v cmd='openssl x509 -noout -subject' '
        /BEGIN/{close(cmd)};{print | cmd}' < /etc/ssl/certs/ca-bundle.crt

This will produce a long list of responses of the form:

    subject= /C=US/O=MyCorp/CN=root-ca-2048

Step 4 above answers the question, the others provide context for the unwary.