Raspberry Pi 2 review and ideas

Click For Summary

Discussion Overview

The discussion revolves around the Raspberry Pi 2, exploring its features, applications, and various projects participants are undertaking with the device. Topics include server setup, project ideas, and experiences with different configurations and uses, including security considerations.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification
  • Debate/contested
  • Experimental/applied

Main Points Raised

  • Some participants highlight the technical specifications of the Raspberry Pi 2, noting its quad-core processor and RAM capabilities.
  • One participant shares their experience of using an earlier model for a gunshot detection project, emphasizing the system's limitations under heavy load.
  • Several users discuss their ongoing projects, including setting up a Tomcat server, music servers, and portable VoIP services.
  • Participants mention security measures they are implementing, such as SSL with client certificates and IP address blacklisting to protect their servers.
  • There is a correction regarding the processor's clock speed, with some participants noting it is 900 MHz rather than 90 MHz.
  • One participant expresses frustration with hacking attempts on their server and discusses measures taken to mitigate these threats.
  • Another participant shares their experience with server failures due to log file management issues, leading to a complete OS reinstallation.

Areas of Agreement / Disagreement

Participants express a range of experiences and opinions regarding the Raspberry Pi 2, with no clear consensus on the best practices for security or project implementation. Disagreements arise over technical specifications and the effectiveness of certain security measures.

Contextual Notes

Some discussions reveal limitations in knowledge about server security and the implications of using certain configurations. There are also unresolved technical challenges related to project implementations and system failures.

Who May Find This Useful

This discussion may be useful for hobbyists, educators, and professionals interested in exploring the capabilities of the Raspberry Pi 2, particularly in server applications, security practices, and project development.

Borg
Science Advisor
Gold Member
Messages
2,349
Reaction score
5,128
Haven't seen a thread on this before so I'll start one. The Raspberry Pi 2 is really a marvel. For $30 you get a 90MHz quad-core processor and 1GB RAM on a Linux platform. The platform also comes standard with an ethernet connector, 4 USB ports, HDMI, and a micro SD slot.

I picked up my first one today with a 32GB memory card. I intend to install a Tomcat Server and a database as support to the D3.js data visualizations that I've been working with lately. I'll post occasional updates as I go along. Feel free to jump in with your projects or ideas.

Let the games begin! :woot:
DSC_7899.JPG


First step is to install the OS. This is a good video.
 
Last edited:
  • Like
Likes   Reactions: jedishrfu, Kia Neves, FactChecker and 1 other person
Technology news on Phys.org
We did a cool project on an earlier model to detect gunshots and activate a servo. It taxed the system quite a bit. We used Python to do the signal analysis from files created every second from the audio recording command. It was very io intensive.
 
  • Like
Likes   Reactions: Borg
I got the OS installed and have connected using HDMI to a TV and Putty, and Filezilla from my laptop. Installed Tomcat, started it, opened a firewall port and checked it from my phone. Things are working well so far.
 
Last edited:
  • Like
Likes   Reactions: jedishrfu and Lapidus
I used one with the Super Moon sensor.
https://www.physicsforums.com/threads/power-from-the-super-moon.765429/#post-5224011

I'm using a old COBALT RaQ-2 case to install an RPi2 (or two) for a music server now.

Original. (with dead Sparc Station 10 for another PI retro case project)
22711968971_f6e2a0b1bc_z_d.jpg

Rebuild with PI card installed on the original HD tray. Need to interface the original LCD and buttons to the GPIO on the PI.
22544218020_94307a9bbf_z_d.jpg

I'm in the process of writing a panel driver for Raspbian Jessie as the OS to display and control
the music selections while using Icecast2 and MPD (Music Daemon Player) to play music on a NFS mounted volume
from the main file server.
 
  • Like
Likes   Reactions: jedishrfu, Lapidus and Borg
Side note on the Tomcat server. It's only been a few days and the server has been scanned by IP addresses in Poland, France and Russia. Looks like I'll be building a blacklist for when I lock it down and actually put some content on it.
 
  • Like
Likes   Reactions: jedishrfu
I use one at work,
Originally had a first version PI, but needed a bit more power.
I've put on a 4" TFT display and a RS485 shield and use it as a portable serial line debugging tool. It helped me fix a site that has been having problems for 5 years on my first trip (not a bad way to impress the higher ups)

I had originally bought it to try and drive an LED matrix display. I worked on it when I was off on one of my coop placements. I neglected to bring any of my other tools (no oscope or multimeter). Don't judge me too harshly but it took me 3 weeks of tinkering to finally figure out that the matrix display required 5v inputs and the PI can only do 3v
/FACEPALM
 
  • Like
Likes   Reactions: jedishrfu and Borg
Finally got some time and figured out how to set up SSL with client certificates! I have struggled with understanding the process of setting up and using certs for years but it looks like I've finally figured it out. I created my own CA and then signed a server cert and user cert with it. The server cert is in my server keystore and the user cert is in the browser. The only way to connect now is with the user cert! Now I can actually code something. :woot:
 
  • Like
Likes   Reactions: jedishrfu
Borg said:
For $30 you get a 90MHz quad-core processor and 1GB RAM on a Linux platform.

I believe that clock speed is an order of magnitude off!

I spoiled myself with one this Christmas... I'm all over it!
 
  • Like
Likes   Reactions: jedishrfu and Borg
falling cat said:
I believe that clock speed is an order of magnitude off!
Yes. Typo on my part. It has a 900 MHz processor.
 
  • Like
Likes   Reactions: jedishrfu
  • #10
I was at a Christmas party last week and someone told me that they have three Raspberries at work. He uses one of them to provide portable VoIP phone services for when he travels. I'll have to look into that one.

Another update on the server. Although I had gotten the two way certificates to work, I couldn't access it from a mobile phone because the certs were built from my own certificate authority. So, I've opted for one-way certificates with Spring security and multiple levels of validation. All pages now check a whitelist of top-level US domains, followed by blacklisted IP addressses within the whitelist, country of origin checks against the IP address, and lastly, a user login screen that validates against users in a Mongodb database on the Pi. I still want to add a check for multiple login failures from unknown IP addresses.

Most of the projects that I've worked on in the past have made security a priority but always after coding a large chuck of the program first. It's nice to build a server for a change that builds in security first. Now I can get to the business of building the tools without wondering who might be trying to break in.
 
  • Like
Likes   Reactions: jedishrfu
  • #11
Still coding away at the server. Building the architectual framework has taken a lot of time but it is coming along nicely.

ServerInfo.jpg


As the note at the bottom states, I am tracking hacking attempts and displaying them in my administrative page.

Intrusions.jpg


As you can see, the largest number of attempts occurred on the 7th from http://whatismyipaddress.com/ip/88.214.230.173. If you zoom in on the map, it resolves to the Kremlin. :wideeyed:
 
  • Like
Likes   Reactions: cpscdave
  • #12
The beginnings of a financial page are in place.
proxy.php?image=http%3A%2F%2Foi63.tinypic.com%2F9gzz2v.png


stockPage.jpg
 
  • Like
Likes   Reactions: jedishrfu and cpscdave
  • #13
Tired of seeing these bottom feeders trying to find vulnerabilities on my server that they can sell.
Goodbye SHODAN.
sudo iptables -A INPUT -i eth0 -s 66.240.0.0/16 -j DROP
sudo iptables -A INPUT -i eth0 -s 71.6.0.0/16 -j DROP
sudo iptables -A INPUT -i eth0 -s 198.20.0.0/16 -j DROP

Shodan users are able to find systems including traffic lights, security cameras, home heating systems as well as control systems for water parks, gas stations, water plants, power grids, nuclear power plants and particle-accelerating cyclotrons; most have little security. Many devices use "admin" as their user name and "1234" as their password, and the only software required to connect to them is a web browser.
 
  • Like
Likes   Reactions: jedishrfu
  • #14
Borg said:
Tired of seeing these bottom feeders trying to find vulnerabilities on my server that they can sell.
Goodbye SHODAN.
sudo iptables -A INPUT -i eth0 -s 66.240.0.0/16 -j DROP
sudo iptables -A INPUT -i eth0 -s 71.6.0.0/16 -j DROP
sudo iptables -A INPUT -i eth0 -s 198.20.0.0/16 -j DROP

Huh?

Are you saying you've applied stealth tech to your server so that SHODAN can no longer find it?
 
  • #15
jedishrfu said:
Huh?
Those are the ip address blocks that they are pinging me from. I'm dropping all requests from those address blocks so that it looks like there isn't a server for them.
 
  • Like
Likes   Reactions: jedishrfu
  • #16
Got it! Stealth a way of life in the internet age!
 
  • Like
Likes   Reactions: Borg
  • #19
jedishrfu said:
Wow that's a great resources! Thanks.
Glad that you found it useful. :woot:
 
  • #21
After nearly a year of running without any issues, the pi stopped responding this week. I suspect that I let the log files get too big and fill the hard drive to the point of not being able to run the OS properly. :oops: I tried several ways to get in and remove some of the files so that it would start but it seems to be a lost hope. I'm reformatting the SD card and completely reinstalling the OS now... :oldruck: Oh well. I'll see how well I documented the installation and updates over the last year. :nb)
 
  • #22
Borg said:
After nearly a year of running without any issues, the pi stopped responding this week. I suspect that I let the log files get too big and fill the hard drive to the point of not being able to run the OS properly. :oops: I tried several ways to get in and remove some of the files so that it would start but it seems to be a lost hope. I'm reformatting the SD card and completely reinstalling the OS now... :oldruck: Oh well. I'll see how well I documented the installation and updates over the last year. :nb)

Is it a SD card or USB drive that filled? I've had a few problems with SD cards causing file corruption over long periods of time. Most are just not designed for long term file updates of the type seen with a Linux OS. I like to NFS mount on the RPi any work or heavily used directories from a server designed to handle file accesses.

I know these cards are reliable.
https://www.amazon.com/dp/B010Q57T02/?tag=pfamazon01-20
 
  • Like
Likes   Reactions: Borg
  • #23
It was a class 10 SD card. I'm not sure what the problem was exactly but I reformatted it and it's running again. This time, I'm going to put the mongo data files and logs on the USB that's also mounted but it's only 16GB. I'll look at getting a larger one later.
 
  • Like
Likes   Reactions: nsaspook

Similar threads

RadioInstigator: Building a SIGINT
  • · Replies 5 ·
Replies
5
Views
4K