ramblings.narrabilis.comHome | ramblings.narrabilis.com

Home About About sub-navigation CV (Résumé) Neil Grant Uphills Bash’isms Bash’isms sub-navigation Howto change the extension of multiple files Howto iterate through an input stream without a subshell or a read. Howto loop based on some iterator Howto use arrays in bash to store indexed information iptohex (convert an ipaddress into hexadecimal) pingmany sshdel delete ssh key by line number update_machine (update the config files on a machine) Books Books sub-navigation Mastering Puppet Second Edition Troubleshooting Puppet Puppet Cookbook Third Edition Mastering Puppet Puppet 5 Cookbook Narrabilis uphillian Talks awk loop through input I have a list of objects and I want to rewrite them with a prefix and suffix. I couldn’t find a good example so I had to work it out myself. awk ’{ for (i = 1; i = NF; i++) { printf "prefix-" $i "-suffix " } print}’ Audio after Fedora 35 upgrade Audio stopped working after I upgraded from 34 to 35. I had pipewire, but also had pulseaudio. This link gave the secret sauce: $ sudo dnf swap allowerasing pipewire-pulseaudio pulseaudio Had to logout and log back in, but after that, audio was back to normal. mousemapper update Recent update changed the event name for Axis events, so I had to update my mousemapper script https://github.com/uphillian/wayland-mouse-mapper The Axis changed from -15 +15 to -15/120.* +15/120.* so I had to update the expansion in bash to %%\.* to remove all the extra stuff. New version seems to work alright so far. I hardcoded my mouse device this time. Retropie with 2 GPIO Controllers - Only one working - 1/2 Not Configured Backstory I bought a Pandora Box and was playing with it for a while, but didn’t like that I couldn’t add games myself. So I replaced the Pandora board with a Raspberry Pi 4. I wired up the joysticks using the GPIO pinout from https://github.com/recalbox/mk_arcade_joystick_rpi The Pandora uses a 40 pin connector, so I purchased a 40 pin breakout cable to rewrite the 40 pin to the GPIO on the Pi. https://smile.amazon.com/gp/product/B01EV70C78/ puppet modulepath problem "Resource type not found" While setting up some cluster machines to run masterless I ran into this bug. I had a directory structure like this: code module1 manifests module2 modules module3 manifests When running puppet apply with the modulepath code:code/module1/modules I ran into this error, specifically using the logrotate module. Error: Evaluation Error: Resource type not found Logrotate::Size (file: code/modules/logrotate/manifests/conf.pp, line: 32, column:12) ssh public key / private key mismatch I updated my private key and added the public key to the authorized_keys on my target hosts and it didn’t work. I ran a few verbose connections to see that the key was being sent, but not accepted. Turns out the old version of ssh on this server doesn’t generate the public key from the private key, it reads the id_rsa.pub file to send the public key. Since this public key doesn’t match what’s in authorized_keys, I was denied. The solution was to delete the public key. Alternatively, you can generate the public key with ssh-keygen. Linux System Troubleshooting Slides from LISA 2019 Linux systems troubleshooting # LISA2019 https://www.slideshare.net/ThomasHowardUphill/linux-system-troubleshooting Process (ps) display shortcuts in bash I gave a talk on processes and made some simple shortcuts to show processes matching patterns. psg ps - grep, grep the process listing for something and show the parent pid, sort by pid. function psg() { thing=$1 sort=$2 if [ -z $2 ]; then sort=’pid’ fi ps -eo ’pid ppid stat cmd’ sort $sort| awk ’NR==1 {print}; /$thing/ && !/awk "NR==1/ {print}’ } psgi ps - grep case insensitive. Grub2 Dual Boot EFI Secure Boot Linux / Windows I just got a new laptop with Secure Boot and was having trouble getting Windows and Fedora installed in a dual boot configuration. I read a few posts on how to do it by changing the bios to Legacy mode but that didn’t seem like much fun. Fedora 30 installed to secure with no problem, so I knew it was possible. I started by paritioning the disk with a GPT partition table and the following partitions: Virtualbox Headless Command Line Hacks For reasons I’m running vagrant with VirtualBox inside a docker container. Most of the time this goes great and no problems, but when it fails it’s difficult to see what’s happening on the machine. I’ve tried and failed to get VNC going on the vm running inside the container. I should note that my problem is with Windows VMs, with Linux VMs it’s never a problem to get console. My workaround for Windows is to use screenshots and send keystrokes to the vm via vboxmanage. First step is to get the uuid or name of the vm Pagination Current page 1 Page 2 Page 3 Page 4 Page 5 Page 6 Page 7 Page 8 Page 9 … Next page Last page Links Follow @uphillian github.com/uphillian LinkedIn/in/thomasuphill amazon.com/author/uphillian Books: - Puppet 5 Cookbook - Fourth Edition - Mastering Puppet Second Edition - Mastering Puppet - Puppet Cookbook 3rd Edition - Troubleshooting Puppet Springdale Linux Author info Thomas Uphill Thomas is a meat popsicle. Thomas started working with UNIX while at SFU and UBC in Vancouver. Starting out on IRIX, HPUX and Solaris, he quickly transitioned to Linux in the early 90s. He has been a System Administrator and a Developer working mainly in Python and C. He’s written several technology books, many dealing with Puppet and Configuration Management. He is available for side projects under his LLC, https://uphillian.com He lives and works in Seattle, in Pacific Northwest tradition he is an avid Mountain Biker and...