Overview System administrators frequently need TLS certificates for systems that are not publicly accessible (and can leverage OpenSSL CA.pl as a solution), including: A public certificate authority may not be appropriate for these systems, especially when their hostnames are only resolvable … [Read more...] about How to Create a Private CA with OpenSSL CA.pl
openssl s_client commands and examples
The s_client command from OpenSSL is a helpful test client for troubleshooting remote SSL or TLS connections as well as check whether a certificate is valid, trusted, and has a complete certificate chain. The post strives to walk you through various examples of testing SSL connections with different … [Read more...] about openssl s_client commands and examples
Apache Access Log IP Address
This article will document how to sort the apache access log IP address list. You may be analyzing the ip addresses in a given apache access log for any number of reasons, including DDOS attacks. We will document a single command to extract the unique IP addresses, count them, and sort them by most … [Read more...] about Apache Access Log IP Address
How to Install OpenSSL on Ubuntu
This article will demonstrate how to install OpenSSL on the Ubuntu Linux platform. Most if not all installations of Ubuntu include OpenSSL by default. If you find yourself with an instance of Ubuntu that does not already have OpenSSL installed, then this article is for you. The examples in this … [Read more...] about How to Install OpenSSL on Ubuntu
Linux socket data on servers
This article will demonstrate how to show Linux socket data on servers, both Redhat and Ubuntu. One primary use case for obtaining this kind of data is when a Linux subscription or support console wants to properly license your organization based on number of sockets. The script below is scalable to … [Read more...] about Linux socket data on servers
Extend Ubuntu Disk Space
The purpose of this article is to extend the Ubuntu disk space. This article will focus on Ubuntu 24.04 LTS, but can likely be used on other Ubuntu versions. You have likely discovered this article because you created a new VM (Virtual Machine) based off of a template and in the creation of the VM … [Read more...] about Extend Ubuntu Disk Space
sshpass ssh password authentication automation
If you are wondering how to automatically authenticate to a linux server with ssh and password authentication, this article is for you. sshpass is for ssh password authentication automation. SSH password authentication is primarily used for keyboard-interactive use cases. sshpass gives you the … [Read more...] about sshpass ssh password authentication automation
How to mount NFS share on Linux
This article will demonstrate how to mount an NFS share on Linux. The instructions will work for both Redhat and Ubuntu Operating Systems. First, let's define NFS. NFS stands for Network File System, which is a distributed file system protocol that allows you to share a directory over the … [Read more...] about How to mount NFS share on Linux