certbotLearn how to get free ssl certificate using certbot and auto-renew certificate.Certificates and KeysLearn how to convert public/private key and certificates to different formats.curlLearn some basics of curl cli tool and usefull combination of its options.Debian2 itemsDisk ManagementLearn how to using system disk management cli utilities to manage disk and perform mount, format, partation and other system disk operations.Enable Serial Terminal (Ubuntu/Linux)Step-by-step guide to enable serial console access for Ubuntu/Linux virtual machines on any hypervisorNetworkingLearn basic of network cli tools in linux/unixrsyncLearn basics of rsync cli to sync files and directories.System InformationTools to gather system informationReset Ubuntu Server PasswordGuide to reset a forgotten Ubuntu server password using the GRUB boot menu, covering both recovery mode and direct root shell methods.User-Permission ManagementLearn how to manage user permissions in Linux/Ubuntu and debian OS.