linux (en)

  • The number of active calls\channels in Asterisk - output to file

    Sometimes it is necessary to determine whether there are enough channels of ground telephone lines, in case if the operator is connected to Asterisk. To collect such statistics in our company, we decided to record every minute (ideally, of course, more often) the number of active calls\channels in Asterisk to file, then plot if required.

    There are two steps in the task:

    1. Output needed data to file in manual mode.
    2. Put the script into cron.
  • How to enable root SSH login in Debian Jessie

    Just after clean Debian Jessie Linux installation, you will install SSH Daemon and then you will encounter an issue when you are not able to login via SSH with root account.

    $ ssh [email protected]
[email protected]'s password: 
Permission denied, please try again.
  • Installing Zabbix cluster in Azure Cloud on CentOS VMs Installing Zabbix cluster in Azure Cloud on CentOS VMs

    Z for Zabbix

    As we all know, monitoring is a huge part of operations and, in my case, DevOps activities. It's one of the elephants, on which any software maintenance rely on, I would say.

    Back to the ground, Azure Cloud is a nice platform, but still, it doesn't have "real" monitoring solution. Not for VMs, nor for any other it's resources. You can say - it has OMS and Azure Monitor, but I've encountered so many limitations and issues with it... Well, my point - is to develop your own bicycle monitoring system to match your environments and needs. 

    Today I'll try to introduce my solution which is: highly avaliable, free and cloud-based.
  • How to check Alpine Linux version inside container How to check Alpine Linux version inside container

    While working with many applications in containers, especially if you're not building them yourself, it's not always clear, what type of base operating system you're using.

    There are two commands below to quickly check Alpine Linux version (will work for most distributives, actually) from the console:
  • Error "ModuleNotFoundError: No module named 'pkg_resources'" after upgrading 'py3-setuptools' package in Alpine Linux container Error "ModuleNotFoundError: No module named 'pkg_resources'" after upgrading 'py3-setuptools' package in Alpine Linux container

    I'm using 'boky/postfix' docker image for emails sending from my Kubernetes-cluster. Recently security scanning system started alerting me about vulnerability in the 'py3-setuptools' package (Alpine Linux), which I can mitigate by upgrading that package to the latest version.

    As usually, I'm going to my custom Dockerfile and updating string for explicit package upgrade...