A DNS, or Domain Name Server, is what helps translate human-friendly URLs into computer-friendly IP addresses. This is what enables our devices to connect to the internet and access the content we want to see. When people change their DNS, it’s usually to enhance either performance, security or both! Below, we’ll take a look at …
DevOps
The OpenSSL s_client command is a helpful test client for troubleshooting remote SSL or TLS connections. This post covers various examples of testing SSL connections with different ciphers, TLS versions, and SSL server certificate analysis. OpenSSL s_client connect openssl s_client -connect example.com:443 Use the openssl s_client -connect flag to display diagnostic information about the SSL …
“Unable to get Local Issuer Certificate” is a common SSL certificate error. It is related to the incomplete certificate chain such as (most commonly) missing the intermediate certificate or missing the root certificate authority (CA) certificate in its trusted certificate store. The fix is to ensure the entire certificate chain is present. To fix the …
An epic is often a larger user story that is broken down into smaller stories in order to be worked on. The important thing to note about epics is that they aren’t just an agile tool. Teams of all work styles can benefit from the epic in Jira because an epic can be a feature, …
certificate chain is an ordered list of certificates, containing an SSL/TLS Certificate and Certificate Authority (CA) Certificates, that enable the receiver to verify that the sender and all CA’s are trustworthy. The chain or path begins with the SSL/TLS certificate, and each certificate in the chain is signed by the entity identified by the next …
Tcpdump with no filters will produce so much output that it will prove very difficult to find traffic of interest. There are numerous filtering expressions available that limit the traffic displayed or captured. Host filters Network filters Port filters Protocol filters Negating a filter match Combining filters Tcpdump provides several options that enhance or …
SSL certificates can have a variety of file extension types. There are a few simple OpenSSL commands that will correctly change the file format easily. We’ll walk you through the process in OpenSSL to convert a certificate to PEM. x.509 certificates file extension Certificate (.CRT) or (.CER) Distinguished encoding rules (.DER) Privacy-enhanced electronic mail (.PEM) …
The best way to find files by name in Linux is using the find command with the “-name” option. This command will search through the directories for files that have the specific word in their name. This can be very useful when you need to find a specific file and don’t know where it is …
Grep is a Linux / Unix command-line tool used to search for a string of characters in a specified file. When it finds a match, it prints the line with the result. The grep command is handy when searching through large log files. Grep lets us enter a pattern of text and then it searches …
ICMP type is the first 8 bits in the ICMP message header. It provides a brief explanation of what the message is for so the receiving network device knows why it is getting the message and how to treat it. For example, a Type 8 Echo is a query a host sends to see if …