Category Archives: Linux

Running a PKI using Smallstep certificates with Docker

Recently, I had to set up a new PKI. I was going to go with the good old OpenSSL but it’s 2021, there must be a more userfriendly and, more importantly, automated approach. There are many open-source possibilities: EJBCA, cfssl, … Continue reading

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Deprecation of apt-key in Debian-based distributions

I recently installed an Ubuntu 21.04 and when I wanted to install Atom editor, I was given the following warning about apt-key being deprecated: After a bit of Googling around, I stumbled on this post on askubuntu.com explaining why apt-key … Continue reading

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Gitlab-runner and docker behind a proxy

After reading many articles and trying many things, this is how I solved it. For docker daemon itself to use a proxy, configure environment variables using systemd file /etc/systemd/system/docker.service.d/http-proxy.conf : For gitlab-runner daemon itself to use a proxy, configure environment … Continue reading

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IPsec tunnel between Ubuntu 20.04 and Mikrotik router using strongSwan

Here is how to establish an IPsec tunnel between an Ubuntu 20.04 host and a Mikrotik router using IKEv2. The 2 endpoints of the tunnel are: ubuntu.xentoo.info : the Ubuntu server. This server has a local private subnet 10.0.0.0/24 and … Continue reading

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Install Firely III on Ubuntu 19.04

“Firefly III” is a (self-hosted) manager for your personal finances. You can find more about it on the following sites: github.com/firefly-iii/firefly-iii docs.firefly-iii.org/ Install prerequisites Let’s first install the requirements to run Firefly. Firefly documentation says it runs on PHP 7.2 … Continue reading

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Compile pjsip with pjsua on Ubuntu 16.04

As a personal note to myself :-) apt-get install make gcc pkg-config libasound2-dev wget www.pjsip.org/release/2.6/pjproject-2.6.tar.bz2 tar -xjf pjproject-2.6.tar.bz2 cd pjproject ./configure && make dep && make sudo make install sudo cp pjsip-apps/bin/pjsua-x86_64-unknown-linux-gnu /usr/local/bin/pjsua That’s it!

Posted in Computer, Linux, VoIP | 1 Comment

Extend snmpd to add detailed CPU statistics, per CPU (again)

For easier use with Cacti, it is easier to group statistics per type instead of per CPU. So you would have a parent OID for CPU time spent by user with many values (one per CPU). Put the following in … Continue reading

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Extend snmpd to add detailed CPU statistics, per cpu

I needed to export detailed CPU statistics from Linux servers using SNMP. While UCD-SNMP-MIB export some detailed stats, it only does it for the whole system. I may have missed something easier though :-) So here is a BASH script, … Continue reading

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Unetlab: create a QEMU image

So you have your Unified Networking Lab (UNL) server running and you want to use arbitrary QEMU images with it. Here is how to create one. All UNL data is stored under /opt/unetlab , images are stored under /opt/unetlab/addons and … Continue reading

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Ubuntu 14.04 and USB to Serial ch341 (chinese device from Ebay)

You can find pretty cheap USB to Serial devices on Ebay. I bought one and received a device using a chip ch341. Unfortunately, the drive is bugged in Ubuntu 12.04 and 14.04. Fortunately, there is patch to fix it. Here … Continue reading

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