It's good to understand what is happening behind the scenes, but you can shoot yourself in the foot in so many ways building your own CA. Please use a tool like<p><a href="https://sourceforge.net/projects/xca/" rel="nofollow">https://sourceforge.net/projects/xca/</a><p>(Don't disqualify just because it is still on SF, it's old, battle tested and IMHO super useful for small, homegrown CAs)