How do I view the details of a digital certificate .cer file?

OpenSSL will allow you to look at it if it is installed on your system, using the OpenSSL x509 tool. openssl x509 -in cerfile.cer -noout -text The format of the .CER file might require that you specify a different encoding format to be explicitly called out. openssl x509 -inform pem -in cerfile.cer -noout -text or … Read more

Any benefit or detriment from removing a pagefile on an 8 GB RAM machine?

TL;DR version: Let Windows handle your memory/pagefile settings. The people at MS have spent a lot more hours thinking about these issues than most of us sysadmins. Many people seem to assume that Windows pushes data into the pagefile on demand. EG: something wants a lot of memory, and there is not enough RAM to … Read more

Using DD for disk cloning

dd is most certainly the best cloning tool, it will create a 100% replica simply by using the following command. I’ve never once had any problems with it. dd if=/dev/sda of=/dev/sdb bs=32M Be aware that while cloning every byte, you should not use this on a drive or partition that is being used. Especially applications … Read more

How to use Let’s Encrypt DNS challenge validation?

Currently it is possible to perform DNS validation, also with the certbot LetsEncrypt client in manual mode. Automation is possible as well (see below). Manual plugin You can either perform a manual verification – with the manual plugin. certbot -d bristol3.pki.enigmabridge.com –manual –preferred-challenges dns certonly Certbot will then provide you instructions to manually update a … Read more

Do systemd unit files have to be reloaded when modified?

After you make changes to your unit file, you should run systemctl daemon-reload, as outlined here. daemon-reload Reload systemd manager configuration. This will rerun all generators (see systemd.generator(7)), reload all unit files, and recreate the entire dependency tree. While the daemon is being reloaded, all sockets systemd listens on behalf of user configuration will stay … Read more