Hello. I have got a VPS with my own IP from a webhosting company. We are sellings domains and hosting to our clients. On of our clients bought a certificate for his domain, and admin of our VPS install it. In SSH it is in etc/ssl certs, openssl.cnf and private ( Apache2 on Debian 7.9 ).
If I would like to use letsencrypt for other clients ( domains ), do I need to install certbot or do I not need to do this since openssl i already installed ? If I install certbot, will there be a conflict with our existing certificate or can they work simultaneously?
If you need more details, I can provide, I have got access to SSH.
certbot and openssl are two rather different things. And neither one explicitly requires the other.
The answer depends on how the first cert was installed and if certbot can coexist with that method.
The certificates should not be a problem as they are stored in different places and generated via different methods.
But again, without knowing how the first cert was installed there is not way to be 100% certain of anything.
Yes, please be clear about how the first cert was installed and how it is being maintained.
I do not know if I am qualified. I can do simple staff in linux ( make folders, installing things, make symlinks so on, not very difficult ). So will there be a conflict installing certbot when the previous SSL was installed using SNI ?
SNI stands for Server Name Identification - It is not a software.
So it can't conflict with any software.
SNI is a way of providing separate access to individual server names while using the same IP.
All the modern web servers employ SNI.
So, to answer your question... NO, certbot does not conflict with SNI, it actually has several plugins that use SNI.
But that "NO" doesn't remove the possibility that the installation of cerbot will not create a conflict with any other software in your system.
As the recommended method (certbot-auto) will also install several dependencies (like python).
The certbot itself can't conflict with anything else but I can't be 100% certain about the addition/modification of the dependencies and their resulting effect on your system.