I got the following error message when attempting to upgrade RPM packages: Oracle Linux 8 introduced a bug with a package called rpm-plugin-selinux (details: rpm-plugin-selinux-4.14.3-28.0.1.el8_9) which prevents RPM packages from being installed correctly, either by dnf/yum or manually. The solution, as shown in this Oracle community forum is to downgrade the package rpm-plugin-selinux like that:…
This is a very technical and a limited solution to Cisco AnyConnect issue with unknown certificate on Linux (Ubuntu 22.04). AnyConnect version is 4.10. I hope this post will help others with a similar problem. The issue is around SAML authentication (an embedded web browser attempting to complete the authentication process), and its failure to…
Using custom mail aliases to run scripts is an existing practice. However, on modern Linux distributions it is blocked as a security risk. Following Postfix common guidelines do not allow for it to run the scripts. It reports the script as called, however – it does actually nothing. This has been verified on Oracle Linux…
GRUB2 password protection, secure Ubuntu boot loader, prevent unauthorised boot menu changes, enhance system security. In previous posts in this blog I have explained how to protect the system by disk encryption with a password retrial from the TPM. In another post, I have given some wider overview of system security and protection, but there…
I’ve been using a WordPress Docker for some time now. My Docker is invoked through the docker-compose toolset, and it generally functions well. However, at times, specific configurations are needed. For instance, when adjusting the PHP file size limitation or adding mod_headers to address CORS issues on WordPress. The key is to override the Docker…
With the migration of Enterprise Linux to ‘chronyd’ ntp clock toolset, some of the more common commands were deprecated, and do not exist anymore. In this article I will go over the most common uses I have in the context of NTP, and how to address them using ‘chronyc’ command line. Perform ‘ntpdate’ command A…
