This article is part of the following series. To check the disk size in Linux, you can use lsblk, fdisk, or parted commands. All these commands are available in most Linux distributions. They provide information about disk size, partition…
An SPF (Sender Policy Framework) record is a type of TXT record in our DNS zone file. SPF records help identify which mail servers are permitted to send email on behalf of our domain. Adding an SPF record can help…
Introduction A PTR (Pointer) record is the backbone of reverse DNS lookups. While a normal DNS lookup (an A or AAAA record) maps a domain name to an IP address, a PTR record does the opposite — it maps an…
DNS MX record is short for mail exchange. It is used to direct email to a mail server. The MX record indicates how email messages should be routed when we send out an email. The best way is to check…
A port is a virtual numbered address that’s used as a communication endpoint by transport layer protocols like UDP (user diagram protocol) or TCP (transmission control protocol). Network ports direct traffic to the right places — i.e., they help the…
An SSL certificate helps to secure the communication between a client (such as a web browser) and a server (such as a website). If the certificate has expired, it can no longer be trusted to secure this communication, and an…
An SSL cipher, or an SSL cipher suite, is a set of algorithms or a set of instructions/steps that helps to establish a secure connection between two entities. SSL cipher suites determine the method through which a secure connection will…
SSL (Secure Sockets Layer) connection is a connection that provides secure communications on the Internet for such things as web browsing, e-mail, instant messaging, and other data transfers. Although SSL was replaced by an updated protocol called TLS (Transport Layer…
An SSL/TLS certificate is a file installed on a website’s origin server. It’s simply a data file containing the public key and the identity of the website owner, along with other information. Without a server certificate, a website’s traffic can’t…
We have two methods to use update-ca-trust or trust anchor to add a CA certificate on Linux. Understanding Root CA certificate SSL certificates operate on a structure called the certificate chain — a network of certificates starting back at the…
