A Fully Qualified Domain Name (FQDN) is the complete domain name of a specific computer, or host, online. A FQDN gives its precise location in the hierarchy of DNS records. It is the complete address for websites and other computers and entities accessing the Internet resolving to the root domain. An FQDN is comprised of …
David Cao
To fix “to use the the ‘ssh’ connection type with passwords, you must install the sshpass program”, we need to install sshpass package in our ansible control machine. What is sshpass? Sshpass is a utility that allows you to store and use your SSH password in a secure way. Sshpass is typically used in conjunction …
An SSL (Secure Sockets Layer) certificate is a digital certificate that authenticates the identity of a website and encrypts information sent to the server using SSL technology. Encryption is the process of scrambling data into an undecipherable format that can only be returned to a readable format with the proper decryption key. How to choose …
AAAA records, also known as “quad-A” records, are a type of DNS record used to map domain names to IPv6 addresses. They are similar to A records, which are used to map domain names to IPv4 addresses, but are designed specifically for IPv6 addresses. IPv6 addresses are four times larger than IPv4 and contain 8 …
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 detect and prevent spammers from sending email messages with forged From addresses on our domain. …
HTTPS is secure and is on port 443. Information that travels on port 443 is encrypted using Secure Sockets Layer (SSL) or its new version, Transport Layer Security (TLS). Using HTTPS also helps minimize an attack by a hacker by identifying open ports and then blocking access with a firewall. It is highly advisable to …
MX Lookup means to perform the MX Record Lookup in the DNS. It is used to check the MX Record to find the internal & external mail servers for a particular domain. MX Record The DNS MX record is a DNS record that routes the email to the correct email server. The MX record tells …
This post describes how to see TCP connection establishment and termination as packets using tcpdump on linux. Preparing Install the following commands on our linux. tcpdump nc telnet netstat Start a TCP connection establishment Start TCP connection using nc command with l,k option. Open another terminal and verify 12345 port is listening using netstat command. …
In networking, a port is a virtual place on a machine that is open to connections from other machines. Every networked computer has a standard number of ports, and each port is reserved for certain types of communication. Think of ports for ships in a harbor: each shipping port is numbered, and different kinds of …
DNS propagation is the time for DNS record updates to take effect on all servers. DNS Changes are not instant because nameservers cache domain record information for a specific duration before refreshing. Some users may still be served a cached version of our site until all servers have completed propagation. DNS Propagation Time So, how …