I have installed sendmail and trying to use a basic mail function in a php page that works on another server. Have tried a few command line test emails that both worked fine. Successful tests: ```Created a txt file, t...

Pretty new to managing a server via the command line. Have seen lots of tutorials about the 'apt-get update' command line and frequently see updates when logging in via terminal. Is it necessary to run 'apt-get UPGRAD...