Ceph is a distributed storage system use in Cloud environment. Recently I’ve been facing an I/O congestion during night period.
This I/O saturation is impacting the application performance on OpenStack even if the system was really resilient to this activity level.
In this post I’ll explain why I had a such situation on the CEPH infrastructure and what are the settings to modify this I/O level.
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Raspberry Pi is a good solution for creating low-cost, powerful embedded devices when you have no need of self powered solution.
I had to create a such device recently to make a programming machine for my IoT devices. I was looking for a compact solution, powered with PoE, industrial grade, able to run a Java program and host a custom HAT with my home-made chip programmer.
Here you see a picture of the first prototype of this product with the different components visible: The green board is a Rapsberry Pi compute module CM3+ with 16GB eMMc flash drive. The blue motherboard is a Waveshare PoE board for CM3+. The Black board is my custom HAT hosting the programming solution based on a STM32.
In this post, I’ll detail a bit these different components and the way they are configured to illustrate how to easily make a such system alive.
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Helium is a crowdsourced-crypto-blockchain-Iot network working with LoRaWan. With all these trendy name, for sure they had the key elements to raise a large amount of money. That’s great for the development of this technology.
I’ve decided to write about this IoT network after an interesting talk given at the Zurich IoT meetup today (thank you CoVID-19 for making us the opportunity to reach such event, today online, bad things can get positive sometime).
Helium is a crowdsourced network. It means, like for TheThingsNetwork or Amazon Sidewalk, the infrastructure, at least the gateways part (antennas) are provided by anybody, basically you and me. That way the network deployment costs are really limited and the network have no boundaries.
Compared to TTN, Helium network is “crypto-blockchained” basically, the gateway owner are mining different challenges like registering some network change, proving the location of a gateway, cryptocurrency transactions… For this work, for maintaining the network architecture and relaying the messages, the gateway’s owner are earning HNT (Helium Network Tokens) ($2.24 each today).
Compared to TTN where you make it running for free, just because you are convinced about the sharing economy, Helium base its business model on a promise of getting some money back from your investment the gateways (+energy, communications…).
Helium is an IoT network, a LPWAN for being more precise. It relies on LoRaWan standard protocol & gateways. You need to add an Helium miner software on a backend system to make it running.
So they are looking to Uber-ize the telecom domain, at least this is what they are expecting.
Continue readingShort tips: when a drive has been formatted for Linux (like a SDCard for a RPI) and you want to clean it ans reuse it as a normal (Fat32) drive, you can’t do it from Diskutil graphical tool.
Continue readingWhen you want to transfer some UDP protocol from a remote server not directly accessible from your local host you can use a combination of SSH and socat to make this communication possible.
The application case is, as an exemple, a SNMP communication with a server in a DMZ to get metrics in a local area dashboard. Like in this exemple.
You have an intermediate host where SSH is accessible you can use as a gateway.
1- on the local host (on the left side), create a SSH tunnel with a TCP port forwarding (here 10000).
ssh -L 10000:localhost:10000 **gateway_host_ip**2- on the gateway host, route the traffic received from the port we have previously associated to the UDP target host:port
socat tcp4-listen:10000,reuseaddr,fork UDP:**target_host_ip**:**udp_port**3 – on the local host, route the traffic received from the given UDP port to the previously associated TCP port for tunnelling
socat -T15 udp4-recvfrom:**udp_port**,reuseaddr,fork tcp:localhost:10000That’s it.
I’m using STM32 Cube IDE suite for STM32 development. This suite is based on Eclipse and GCC and it works quite well. In a recent project I was looking for some optimization I could apply on top of the basic existing settings to reduce the FLASH and RAM size.
In this post I want to share what I found and how it helped me.
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Yes, I’ve got one of these LoRaWan light saber I was looking for, since a while! For this I really thank you Wifx who helped me to get one. I know this is really unusual for them to work with blogger, so thank you for your trust. So honestly, even if I’ve been sponsored to get the device, I’m really happy to make that gateway test. As I said this gateway is one of my favorite since a while. The reason are a really compact outdoor design. It makes the difference 😉
I did not made a test previously because this have a cost, about 500€, (549CHF) this not much expensive but a bit high regrading my non-profit activity on TheThingsNetwork local deployment.
Now, I’m done telling you my life, we can see what this gateway is proposing !
Continue readingI’ve recently made a post on how to make a pandemic alarming system based on low cost connected thermometers. This post was more about the organization model and business model than the technological solution and implementation. So I also wanted to continue to investigate the connected thermometer solution, mainly for the fun. As I’ve been sponsored by digitspace.com for some free hardware, it has been the opportunity for testing contact-less thermometers module.
The design I’m going to propose in this post will not apply to the low-cost connected thermometers as the technology I’m going to use is far more expensive to the one I proposed in my previous post.
That said, this design can be useful for companies, public site or free access thermometer booth anyone would like to design at low cost.
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