Generate a Certificate Signing Request(CSR) with OpenSSL / Linux



Unable to start firewalld, Active: failed (Result: timeout)


Try to start firewalld service via the following command

but get the following error after few seconds no response:


Execute the following command to restart firewalld service


How to encrypt and decrypt .cpt file

What is .cpt extension?

.cpt is a encrypted file format, you can use ccrypt to create and decrypt .cpt file


How to encrypt and decrypt .cpt file

Encrypt a file

Decrypt a file.


How to install ccrypt

Install ccrypt on CentOS

Install ccrypt on Debian/Ubuntu


Convert .cer to .crt certificates for Apache/mod_ssl using OpenSSL

Assume you have a CER is an DER encoded X.509 certificate in binary form, and you want to have a PEM-encoded X.509 Certificate file for Apache.

The following command may help:


Apache/mod_ssl request PEM-encoded X.509 Certificate file