How to display scoped labels inside free version of GitLab
Display scoped labels inside free version of GitLab with the help of Greasemonkey a user script manager for Firefox web-browser. I am using Gitlab free for personal development and operations. Scoped...
View ArticleHow to extract Kafka topic parameters using command-line utilities
Use command-line utilities to extract Kafka topic parameters. Create sample topic. $ ./bin/kafka-topics.sh --bootstrap-server localhost:9092 --create --topic logs --partitions 10 --replication-factor 3...
View ArticleHow to delete Kafka messages
Delete every Kafka message or messages up to the specific offset. Preparations Create sample keep-up-with-topic topic. $ bin/kafka-topics.sh --bootstrap-server localhost:9092 --create --topic...
View ArticleHow to install GitLab runner on Raspberry Pi
Install GitLab runner on Raspberry Pi. I will use previous LXD setup on Raspberry Pi 4 with DietPi operating system. Get the registration token Determine the registration token. Create LXD instance I...
View ArticleHow to configure Grafana application within GitLab instance to accept...
Configure Grafana application within GitLab instance to accept self-signed certificate. Add a self-signed certificate, reconfigure GitLab instance and update Grafana Callback URL. You will see...
View ArticleHow to rotate Kafka logs
Alter Log4j configuration to rotate Kafka logs. By default Kafka uses DailyRollingFileAppender in config/log4j.properties for each configuration file. [...]...
View ArticleHow to install OpenSSH on DietPi operating system
Use internal DietPi utilities is to switch from a Dropbear to OpenSSH Server. List SSH servers. $ sudo dietpi-software list | grep SSH ID 0 | =0 | OpenSSH Client: Feature-rich SSH, SFTP and SCP client...
View ArticleHow to query Docker socket using curl
Query Docker socket using curl. Display Docker version. $ curl --silent -XGET --unix-socket /run/docker.sock http://localhost/version | jq . { "Platform": { "Name": "Docker Engine - Community" },...
View ArticleHow to take the advantage of dynamic DNS resolution in NGINX
Take the advantage of dynamic DNS resolution in an open-source version of NGINX. NGINX version. nginx -v nginx version: nginx/1.18.0 The easiest method to use dynamic DNS resolution is to define single...
View ArticleHow to solve netcat mystery X
Funny netcat issue with additional X characters send over UDP protocol and why this is not a problem. The funny issue Send something over network using UDP protocol. $ netcat -q0 -u remote_address 2000
View ArticleHow to disable GC Logging for Kafka and bundled ZooKeeper
Disable GC Logging for Kafka and bundled ZooKeeper. GC Logging for both of these services is enabled using EXTRA_ARGS variable. Kafka service. $ cat bin/kafka-server-start.sh #!/bin/bash # Licensed to...
View ArticleHow to define control domain memory inside XCP-ng
Define control domain memory inside XCP-ng. Get current control domain memory definition. $ sudo /opt/xensource/libexec/xen-cmdline --get-xen dom0_mem dom0_mem=1840M,max:1840M Define control domain...
View ArticleHow to define cluster groups in Ansible inventory
Define cluster groups in Ansible inventory. Define hosts that will contain multiple application clusters. $ cat hosts [application:children] application_cluster_development...
View ArticleHow to boot ISO file directly from USB drive
Use Ventoy an open source tool to create bootable USB drive for ISO/IMG/VHD/… files. Open Ventoy GitHub releases page and download release for your operating system. I will download...
View ArticleHow to alter memory allocation pool for Kafka and ZooKeeper
Alter memory allocation pool for Kafka and ZooKeeper. GC Logging for both of these services is enabled using KAFKA_HEAP_OPTS variable. Kafka service. $ cat bin/kafka-server-start.sh #!/bin/bash #...
View ArticleHow to rebalance data across HDFS cluster
Rebalance data across HDFS cluster. Inspect balancer paramters. $ sudo -u hadoop -i hdfs balancer --help Usage: hdfs balancer [-policy ] the balancing policy: datanode or blockpool [-threshold ]...
View ArticleHow to ignore certificate verification errors when using wget
Ignore certificate verification errors when using wget. Try to access the address secured by a self-signed certificate. $ wget --output-document - https://nextcloud.example.org --2021-07-16 13:59:59--...
View ArticleHow to identify YubiKey using dynamic device manager
Identify YubiKey device using dynamic device manager to send desktop notification. Inspect device manager information Inspect device manager events to get the YubiKey serial number. $ udevadm monitor...
View ArticleHow to reassign Kafka topic partitions
Reassign Kafka topic partitions. Step 1 Create a sample topic. $ bin/kafka-topics.sh --bootstrap-server localhost:9092 --create --topic cerberus --replication-factor 3 --partitions 15 Created topic...
View ArticleHow to use LVM thin provisioning
Configure and use LVM thin provisioning. Thin volumes are useful for overprovisioning especially for containers. Preparations Install LVM utilities. $ sudo apt install lvm2 Initialize physical volume....
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