I am using SSL certificate signed by Verisign for my VPN Server which is hosted on the public network and my company employees use to connect to company network through this server.
The system use to be online 24*7 and it will be a tough to take a downtime.
In my VPN server, i don't have permission to create or modify the web files (or in simple words, i only have GUI of that machine and from GUI, i can only uploads the certificate file like .pem or certificate chain over the server).
Now, i am thinking to go for the certificate from Let's Encrypt server (for the obvious reason of saving some dollars).
I have some doubts in my mind like -
- Should i go for Let's Encrypt or not ?
- Is it secure to have a certificate from Let's Encrypt ?
- Most important question, I had gone through the procedure for getting a certificate from Let's Encrypt; What i understand was that i have to install ACME tool or some scripts which will do the jobs automatically for me.
Now, i have a limitation that my VPN box doesn't allow me to install anything apart from some specific codes (generally patches) provided by OEM.
Also, in procedure, it was mentioned that ACME (or similar other scripts) will create a temporary file with some garbage text for checking the domain ownership by Let's Encrypt program. My Server doesn't have this capabilities.
What should i do to get the SSL certificate from Let's Encrypt.