push buttons, turn knobs, pull levers
MH-Z19 CO2 sensor reader, logger and visualiser Reads data from UART(serial)-connected MH-Z19 (or MH-Z14) sensor using python 3. If you dare to install nodejs you can visualise the logged data (using html and plotly.js library). Repository: sammcj/CO2-Logger UsageNote this post is from 2016, in 2021 I replaced my custom Co2 loggers with an Aranet4 .
I wanted to try Android for a couple of weeks, I like staying on top of technology, gadgets and making sure I never become a blind ‘zealot’ for any platform or brand.
The OnePlus 3I did a lot of research and decided to try the “Oneplus 3” as it was good bang-for-buck, ran the latest software had plenty of grunt with the latest 8 core, high clock speed Qualcomm processor coupled with 6GB of DDR4 - the specs really are very impressive, especially for a $400USD phone.
note: This is a follow up post from 2015-07-21-rcd-stonith A Linux Cluster Base STONITH provider for use with modern Pacemaker clustersThis has since been accepted and merged into Fedora’s code base and as such will make it’s way to RHEL.
Source Code: Github Diptrace CAD Design: Github I have open sourced the CAD circuit design and made this available within this repo under CAD Design and Schematics Related RedHat Bug: https://bugzilla.
Ever forgotten to add a critical service to monitoring?
Want to know if a service or process fails without explicitly monitoring every service on a host?
…Then why not use SystemD’s existing knowledge of all the enabled services? Thanks to ‘Kbyte’ who made a simple Nagios plugin to do just this!
Scripts and source available here: sql_ascii_to_utf8 The GoalTo be able to take a Postgres Database which is in SQL_ASCII encoding, and import it into a UTF8 encoded database.
Requirements:
Python3 (For RHEL/CentOS 7 yum install python34) python-nagiosplugin My pre-built RPMs or pip3 install nagiosplugin PyNagSystemD The ProblemPostreSQL will generate errors like this if it encounters any non-UTF8 byte-sequences during a database restore:
The most common way to use rsync is probably as such:
rsync -avr user@<source>:<source_dir> <dest_dir> Resulting in 30-35MB/s depending on file sizes
This can be improved by using a more efficient, less secure encryption algorithm, disabling compression and telling the SSH client to disable some unneeded features that slow things down.
This is a quick tldr there are many other situations and options you could consider FIO man page IOP/s = Input or Output operations per second Throughput = How many MB/s can you read/write continuously Variables worth tuning based on your situation --iodepth The iodepth is very dependant on your hardware.
Let’s pretend you have a project on Gitlab called ask-izzy and you want to mirror it up to Gitlab which is located at https://github.com/ask-izzy/ask-izzy Assuming you’re running Gitlab as the default user of git and that your repositories are stored in /mnt/repositories you can following something similar to the following instructions:
Today we launched a mobile website for homeless people
… and it was launched by one of Australia’s many recent Prime Ministers Today alone we served up over 87,000 requestsAs many of you know, I work with Infoxchange as the operations lead.
When I first heard the idea of a website or app for people that have found or are worried about finding themselves homeless in Australia I really didn’t think it made sense - until I saw the stats showing how many homeless people in Australia have regular access to a smart phone and data either via a cellular provider or free WiFi.
If a disk / VDI is orphaned or only partially deleted you’ll notice that under the SR it’s not assigned to any VM.
This can cause issues that look like metadata corruption resulting in the inability to migrate VMs or edit storage.
For example:
[root@xenserver-host ~]# xe vdi-destroy uuid=6c2cd848-ac0e-441c-9cd6-9865fca7fe8b Error code: SR_BACKEND_FAILURE_181 Error parameters: , Error in Metadata volume operation for SR.
“Having a SCSI ID is a f*cking idiotic thing to do.”
- Linus Torvalds …and after the amount of time I’ve wasted getting XenServer to play nicely with LIO iSCSI failover I tend to agree.
The Problem
One oddity of Xen / XenServer’s storage subsystem is that it identifies iSCSI storage repositories via a calculated SCSI ID rather than the iSCSI Serial - which would be the sane thing to do.