https://wiki.kptree.net/ 2026-09-18T18:12:17+00:00 https://wiki.kptree.net/ https://wiki.kptree.net/_media/wiki:dokuwiki.svg text/html 2025-08-09T03:11:23+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.kptree.net/tech_notes:dns?rev=1754709083&do=diff Domain names, domain nameservers, DNS and DHCP Domain names, Domain nameservers, DNS and DHCP are a key part of the internet back bone. * DNS (Domain Name System) resolves the text domain names to the relevant IP (Internet Protocol) addresses. * text/html 2025-08-10T12:30:03+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.kptree.net/tech_notes:pikvm?rev=1754829003&do=diff linux kvm ipmi pikvm bmc PiKVM I purchased a PiKVM kit in 2021, and got it operational at that time. I did not need to use it until recently, 2024-09. Basically a special 'hat' is mounted on a standard Raspberry Pi 4, the smallest memory unit type being sufficient (2 GB). The kit was complete with all the required parts, such as the hat, Raspberry PI, a case, small OLED display and various cables. The PiKVM is V3 HAT with RPi V4 2GB. text/html 2023-12-29T07:24:43+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.kptree.net/tech_notes:nginx?rev=1703834683&do=diff nginx http Nginx On a simple system nginx can be started with /usr/sbin/nginx basically calling nginx executable with defaults. nginx -h nginx version: nginx/1.24.0 Usage: nginx [-?hvVtTq] [-s signal] [-p prefix] [-e filename] [-c filename] [-g directives] Options: -?,-h : this help -v : show version and exit -V : show version and configure options then exit -t : test configuration and exit -T : test configuration, d… text/html 2026-01-23T03:32:30+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.kptree.net/tech_notes:flatpak?rev=1769139150&do=diff linux flatpak snap universal package Flatpak Flatpak is a universal Linux package management system, that is more agnostic than the Linux distributions package management systems. Flatpak currently only works with a desk top environment, it is not for servers. There are other universal package management systems available. One popular example is snap, however this is from Ubuntu and seems propriety in nature. text/html 2025-01-18T13:48:17+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.kptree.net/tech_notes:iperf?rev=1737208097&do=diff linux network testing speed speed speed test testing tech notes technical Network Speed testing Use the iperf3 command to test network speeds. * iperf3 -s to start in server mode * iperf3 -c 192.168.1.10 -t 20 to test server on ip address 192.168.1.10 for 20 tries. * iperf3 -c 192.168.1.1 -t7 -b 2.5G -u 6001 * iperf3 -c 192.168.1.1 -t7 -R -b 2.5G -u 6001 text/html 2024-03-13T13:19:01+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.kptree.net/tech_notes:ansible?rev=1710335941&do=diff linux ansible ansible * sudo apt install sshpass The sshpass package must be installed. * Create a file ansible.cfg in your current folder with the following contents: [defaults] host_key_checking = false * create password less login to remote machines * ssh-keygen text/html 2022-10-18T05:44:24+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.kptree.net/tech_notes:ipv6?rev=1666071864&do=diff linux ipv6 IPv6 summary notes Largely taken from * onemarcfifty * What You Need to Know about IPv6 Link-Local Addresses Address length and format The IPv6 address is 128 bits (i.e. 16 bytes) long and is written in 8 groups of 2 bytes in hexadecimal numbers separated by colons: FDDD:F00D:CAFE:0000:0000:0000:0000:0001 Leading zeros of each block can be omitted, the above address can hence be written like this: FDDD:F00D:CAFE:0:0:0:0:1 We can abbreviate whole blocks of zeros with :: and w… text/html 2024-03-09T02:45:50+00:00 Anonymous (anonymous@undisclosed.example.com) https://wiki.kptree.net/tech_notes:ssh?rev=1709952350&do=diff linux ssh ssh-keygen ssh with key files The advantages of using SSH key-based include: * Improved security * Easier access to ssh (if password keys are not used) Clearly use of unique password encrypted keys gives best security. However if a user has access to you terminal and user password they effectively have full system access anyway.