SysAdmin on Sandro Cirulli

How to exclude a package from being updated on Linux

Sat, 05 Aug 2017 00:00:00 +0000

Sometimes you prefer not to update a specific package in Linux. This may be because you don’t want to upgrade to a new version with new features but no security updates. Or maybe because upgrading requires a service restart that you want to avoid just yet. This was the case for me recently when a new version of Docker came up and upgrading would have restarted the docker daemon and stopped the running containers.

How to map IP addresses in bash prompt

Wed, 30 Dec 2015 00:00:00 +0000

Image: Indeterminate - Public Domain via Commons

I regularly log into different Linux machines on the cloud and find complicated to identify on which machine I am by looking at the bash prompt. In fact, in cloud environments the bash prompt tends to show an ugly internal IP address which I can never memorize. Plus, I always fear to log into the production environment by mistake and run experimental commands intended to be executed in the development environment.

How to transfer files to a remote server

Sun, 20 Dec 2015 00:00:00 +0000

Image: rsync - Fair use license

While using cloud services like AWS it sometimes occurs to transfer files from a local machine to a remote server which is only accessible via SSH keys. Linux utilities like rsync and scp come to rescue in this case. Here is an example of how to transfer files via rsync.

First, make sure that the destination folder on the remote server is writeable. If not, log into the remote server and change the permissions, e.g.: