Configuring Multiple Raspberry Pis

Hi Howard,

Thanks for the information. I looked through your site and I think it’s great. The work you’re doing is amazing to see. I don’t have any criticisms but I am very interested in the details around setting up solar power and what is required to build a computer lab based on it as it seems necessary for rural deployments. I’m also curious if you’ve considered the Raspberry Pi 0 W for any use or if it’s too low powered to help. Thanks again.

James .

Hi James
I don’t know enough about the Pi0, Could I use the same image? If I could then I’ll try it out…
The power we supply is OK for 4 laptops projector pi router and 4 led strips. We could add more Pis but the monitors use a lot more power. If you had the money then having a bigger solar array say 10 panels and more battery capacity say 10 220Ah batteries could run a lab of 10 Pis.
You would have to figure in the desire of a village wanting to use some power for things like freezers which would inevitably be plugged in and could cause battery damage. We always run courses on system maintenance to try to overcome these issues. It costs us about £4000 to fix a school this could easily rum to £10000 if we included a lab. It is a difficult call but we decided to do more schools with what I regard the basic rather than fewer schools better equipped.
I intend to put up detailed calculations on energy use in the next few weeks.
Howard

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Howard,

My reasoning (often flawed).
Starting the class, I am just using a basic desktop image with a PI user (locked), a teacher account and a student account with browsers, Libre office, VNC and a few others for school work. I would like to introduce Scratch which is loaded but somewhat deemed a game by several right now.

I needed to be basic but have programs that will allow users to get acclimated and learn without being too overwhelmed. I opted for Linux over Windows is due to the viruses on most of the PC’s we encounter and potential cost of Windows. If something should go wrong, then the resolution needs to be quick and simple. I only need 1 Micro SD image and 1 of each server and can duplicate them with a USB writer, 5 min per sd or 60-ish per SSD. My laptop options have been a wide range of brands and age that I felt could be difficult being old and slow and could require too many OS images to keep track of.

I have thought about open ldap or the Pi-Net server to make user accounts and saving work more personal, as right know I just have a file server for the students to save work based upon grade and teacher. A lot depends on the teachers grasp.

With the school having 520 students, we decided to build a full-size classroom to better benefit this many students. This will allow us to see what does or doesn’t work and adjust as needed. Having a full class will provide others the opportunity to test drive it onsite and hopefully create new jobs that are so needed. We have a few on the Haitian team that are in school for IT and wanting to learn the system to gain extra computer skills, ability to run a lab, and teach the students and teachers at the school.

My issue right now is that this class is pretty much self-funded and I do 99% of the work. I can only make so many trips a year so I am trying to pick my battles.

Any feedback or suggestions are welcome. I certainly know that I don’t come close to having all the right answers.

Thanks,
Don

You are doing much the same as me! I guess there are no easy routes. I have put Raspbian as the o/s on laptops this with a 250Gb SSD seems to work well. I have been lucky enough to be given a lot of laptops all the same, Fujitsu lifebooks, old but very effective. it certainly makes cloning very easy.
I have put Calibre and Kolibri (with African Story book and Khan academy) on the laptops and RACHEL on the Pi. I also have GIMP and OpenShot on the laptops. Because of limited funds we have focused on installing solar power (up to 3 350watt panels) in several schools rather than focusing on one school. So far, (we have been doing this since 2014) we have done this in 17 schools. We have provided lots more with the Pi with RACHEL and powerbank,20000mA
I guess it’s mostly the teachers who use the equipment for class teaching.
Do you know of any low power 10 inch monitors?
Kind Regards
Howard

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Sorry @jamesk and @SHOMI
I forgot to include the @ bit!
Howard

@jamesk @giakonda Thank you so much for your replies! We are working to implement the Rachel Pi in Sierra Leone. I will definitely come back if we have any more questions.

Thank you for your reply!

Hi Howard,

The pi0 is the $5 USD version of the Raspberry Pi. Its very cheap and the size of half a credit card. You can build an image using a 2B, 3B, or 3B+ for use with the pi0w. I am putting up new images that are more suited for it as Kolibri requires too many hardware resources. I’m wondering if it has a use for deployments in remote areas as the power consumption and price are so low. I think it can handle 5 devices but it may be better for use with a couple of tablets.

Thanks for the info about solar panels. Very interesting stuff! I’m always looking to learn more so I can help find solutions. Monitors seem to be an issue all around as the cost is high as well. I’d like to look into the hardware side of things a bit more soon.

James

You’re welcome! If you have any questions in the future feel free to ask.

Thanks @jamesk
Am I correct in thinking if I take the sd card out of a pi3b+ and put it in a Pi0w it will work?
If this is correct and it can deliver RACHEL to 4 laptops that will be perfect for so many small, almost, villages.
I have not used the Pi 0 before.
If you come across any 10 inch displays for the Pi that are low power and cheap I would be very interested if you let me know.
Thanks
Howard

Hi Again @jamesk
Where can I find the images? Are they on the ftp site.
Kind Regards
Howard

Hi Howard,

You are correct. For now the best way to build an image for the Raspberry Pi 0W is to use another pi with an ethernet port to download the modules and then transfer that storage device to the 0w. I think it’s worth trying out to see if it works for your deployments. The power consumption should be significantly lower and the device is very cheap.

I have added images at the pinned pi images post here. The blue download button should show up when you go to the link for an image. I am having issues uploading to the FTP right now so hopefully that will be fixed soon.

Kolibri requires a bit too much CPU power to run on the pi0w so I suggest using the static or Kiwix images for it. There is a list explaining supported modules in the readme but basically those images don’t have KA-Lite or Kolibri. You can try any of the images out for testing with the pi0w though.

The pi0w can also boot from USB. It only has one Micro USB port, but you can use a USB OTG cable with your USB flash drive plugged into it. The only requirement is that you have a MicroSD with the file “bootcode.bin” on it. The file is very small so you can use a 512mb or 1gb card and it is only read once at boot time so it doesn’t have to be high speed. USB booting will speed it up.

What is the current cost of the screens you use, or are you using laptops exclusively right now?

James

Thanks James. I’ll get a few Pi0 and try them in June, our next visit.
At the moment we have Fujitsu laptops but I think a small lab of pis is worth a try.
to do this we would need low power screens. 10 inch would be a start.
Thanks for your help.
Kind regards Howard

You’re welcome Howard. Unfortunately the pi0w is not strong enough to operate as a desktop computer or it would be even more useful.

The cheapest place to source screens I have seen is always www.aliexpress.com but it may take some time and the quality varies. I am starting to look into this problem more so I’ll let you know if I find a good solution.

James

Howard,

I downloaded the Static image and loaded the modules via a 3B+ and moved the microsd to the PI 0. I had 4 devices connected with 10 videos between the KAOS and Haiti Futur and a few books pulled and it works well.

Jamesk,

This is a great file for the PI 0 W.
This will help us reach smaller schools and those that do not have the secure structure to leave bigger equipment, not to mention the small amount of power it takes to run one of these.

@SHOMI, I haven’t had a chance to test with more than two devices so that’s great news!

I agree about the plus sides of the 0W model and I really hope it is useful for those smaller deployments. When I started working on Raspbian Stretch support it was with the goal of running RACHEL on the pi 0w so it’s nice to see it properly supported now. The fact that it’s so cheap ( it should be $5USD but the price is double or more in most places ) means it’s easier to supply and replace.

I am looking more at hardware now. Mostly seeing if there’s a good way to use cheaper LCD panels with the pi as a desktop. If you have any suggestions or notes from your experience I’d be happy to hear it.

James

Hi Don,@shomi
Looks like we are on a roll. I have just had 6 laptops running the Bino Fino videos off a Pi Zero as @jamesk said setup on a Pi3+ with a 128Gb SD card (SanDisk extreme) and all worked perfectly.
We are off to Siavonga and Monze at the end of May so this will come in very handy.
Kind Regards
Howard

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I have also tried the image on the smaller format Pi3A and it works fine including Kolibri.
I still prefer the Pi3B+ because of it’s ethernet port. Oh yes while I’m here you might like to know that I have tried it on the Pi3b+ with the power over ethernet hat and that works fine too.

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Very interesting Howard! I’m happy to hear these images are working on different hardware in different configurations. I haven’t tried the Pi3A yet. I’ll have to pick one up and try it.

The latest images and readmes are hosted on the FTP now thanks to @jeremy’s help. The links have been updated in the main post but if you go to the ftp they’re in the /rachelpi_64EN/rachelpi_2019/ folder.

I’ve been looking more at monitor alternatives and I think using LCD panels with a single board computer is the way to go for low power consumption. Something like this project called pinebook which charges from 5v and can run from a power bank.

James

Thanks James. This looks really amazing, I’m going to buy one just to see if it’s real :slight_smile: