Use the following iptables command to rate limit connections per IP. This is useful for preventing a DDoS attack on DNS servers. However, for DDoS protection for your DNS servers, you should be hosting DNS with the big cloud providers like Cloudflare, or running dnsdist in front of your authoritive servers.
Enable older SSH key exchange methods
Insert the following in /etc/ssh/ssh_config to apply it system wide or ~/.ssh/config for just your user. It will enable most algorithms that older devices may need. You might get the following error when accessing old SSH servers on Fedora or other RedHat based distributions with weaker keys. To allow these weaker keys, update the crypto…
Yarn Repository Expire Key Error
When using yarn through the apt repo, the key might expire, giving you the following error when updating apt. Issue the following command to update the key and then update the repository.
Django Query Sets
More information can be found at the official Django Making Queries documentation.
Python Code Snippets
List of files, just filenames, no directories. List files, no directories, full path. Indicate that your string variable is a raw string. Locate the path of Python you are currently using.
Set git username and email address in Windows / VSCode
After installing Git for Windows, a username and email address has to be set or VSCode will give you the following error: To add your username and email address, open up a terminal. I used Powershell in this case and type in the following commands: If the email address used is also in your GitHub…
Create a .pfx/.p12 Certificate File Using OpenSSL
Source: https://www.ssl.com/how-to/create-a-pfx-p12-certificate-file-using-openssl/ The PKCS#12 or PFX format is a binary format for storing the server certificate, any intermediatecertificates, and the private key into a single encryptable file. PFX files are usually found with theextensions .pfx and .p12. PFX files are typically used on Windows and macOS machines to import andexport certificates and private keys. Requirements…
DB_VERSION_MISMATCH error when updating AlmaLinux 8 / RHEL 8 / Rocky Linux
When trying to update the operating system, you might receive an error similar to the following … This can be fixed with the following command to remove the existing database …
Network Policy Server Notes
View the status of logging Enable logging Disable logging
Disable the floppy drive module in Linux(Ubuntu)
Sometimes Linux will mistakenly detect a floppy device and create a reference to it because your system does not actually have a floppy drive and you will see errors on the login screen that look similar to blk_update_request: I/O error, dev fd0, sector 0. I find this frequently happens on a VMWare VM. This doesn’t…