I have rasberry pi with a 3G shield connected to it. Is there a way to gather metrics about the network such as available data capacity/throughput, latency and way to measure contention on the network?
I am assuming that you want to know the statistics for your connection to the internet.
There is a great Command-Line tool for this by sivel which you can install from the command line using:
sudo pip install speedtest-cli
or
sudo easy_install speedtest-cli
and then just run it with the command:
speedtest-cli
and it will give you the results.
For more information please see the project page on GitHub: https://github.com/sivel/speedtest-cli
Related
I'm using buildroot to compile a minimalistic linux with a 4.19-rt kernel. It is supposed to run on a raspberry pi 3b (arm processor). Additionally I want to run it on a x86_64 linux computer and found qemu as an emulation solution for that.
Building linux and kernel and running it on the raspi works. It boots, I can login and use it.
To test qemu I followed this instruction [1]. A recent raspbian with 4.19 kernel is booting fine so qemu seems to be installed correctly.
sudo qemu-system-arm -kernel ./qemu-rpi-kernel/kernel-qemu-4.19.50-buster -hda 2019-09-26-raspbian-buster-lite.img -cpu arm1176 -m 256 -M versatilepb -no-reboot -serial stdio -append "root=/dev/sda2 panic=1 rootfstype=ext4 rw" -dtb qemu-rpi-kernel/versatile-pb.dtb
Bringing 1. and 2. together fails. When I try to emulate any self build linux, qemu only shows a black screen and one CPU is using 100%.
I used the same sdcard.img that works on the real hardware. I also tried to recompile the whole system with a normal 4.19 kernel (without real time). And I tried to build a versatile system (make qemu_arm_versatile_defconfig && make). None of it works.
Command to start the emulation:
sudo qemu-system-arm -kernel zImage -drive format=raw,file=sdcard.img -cpu arm1176 -m 256 -M versatilepb -no-reboot -append "root=/dev/mmcblk0p2 panic=1 rootfstype=ext4 rw" -serial stdio
My main problem is, that there is absolutly no useful output. The command outputs the following
ALSA lib pulse.c:242:(pulse_connect) PulseAudio: Unable to connect: Connection refused
sdl: SDL_OpenAudio failed
sdl: Reason: ALSA: Couldn't open audio device: Connection refused
ALSA lib pulse.c:242:(pulse_connect) PulseAudio: Unable to connect: Connection refused
sdl: SDL_OpenAudio failed
sdl: Reason: ALSA: Couldn't open audio device: Connection refused
audio: Failed to create voice `lm4549.out'
and opens a window for the graphics output (that does not show anything). The message also appears when emulating raspbian so it does not seem to be the reason.
When I run qemu with the prebuild raspbian but without the -dtb argument, I get a message like "Error: invalid dtb and unrecognized/unsupported machine ID". I would at least expect something like this with my self build code. But because there is no output I'm out of ideas what even to google for.
Does someone maybe have an idea what I'm doing wrong or how I get qemu to provide me any useful information on what went wrong?
[1] https://blog.agchapman.com/using-qemu-to-emulate-a-raspberry-pi/
The problem is that a kernel will only boot on a piece of Arm hardware if it is compiled for that hardware. Otherwise it will generally fail, usually by crashing before it is able to output anything useful.
In particular, the QEMU 'versatilepb' machine is completely different to the Raspberry Pi. Any working set of instructions that use that machine type are really running a kernel built to work with the versatilepb board and a raspi userspace/filesystem on top of that. You're trying to build a kernel that has support for only the raspi on a machine that isn't a raspi, which won't work.
It is possible to build a kernel that works on more than one piece of Arm hardware, if you compile in the support for both board types (all the device drivers for both, etc). If you want to go down that path, I would suggest looking at the differences between the kernel config for the kernel that works and your one, and add plausible looking missing things until you find out what is actually required.
Your attempt to boot on QEMU directly from sdcard.img will not work, because QEMU's versatilepb board model does not support direct boot from sdcard (this would require us to run some kind of BIOS/firmware image in the guest, which we don't have). For versatilepb you need to supply directly to QEMU the kernel, possibly an initrd, and definitely the correct dtb for the versatilepb.
You might instead try looking at QEMU's "raspi2" and "raspi3" board models, which really do model the hardware of Raspberry Pis. The disadvantages however are that these models are missing some features and are not very actively developed, so often newer kernels don't boot on them, and also since there is no USB controller model there is no way to get networking. (This is why most blog posts etc suggest using the 'versatilepb' -- userspace doesn't often really care about exactly what hardware it's running on, so unless you're trying to do kernel development you can just run a versatilepb kernel and take advantage of the features like networking that that QEMU model has.)
Advanced Linux Sound Architecture (ALSA) tries to open audio interface device . you must provide audio device in qemu . Because the kernel is compiled with ALSA audio driver and you have compiled sdl library in Buildroot.
I have a Raspberry machine running a program which process data coming from a /dev/ttyUSB0 device.
I want to move that device to another machine and transfer the data to the initial machine so it appears as coming from the original machine.
I feel that socat might be the answer but I am lost in the parameters of the command.
Any help would really be appreciated
This seems to work.
On the server side (were the physical device is plugged):
sudo socat tcp-l:54321,reuseaddr,fork file:/dev/ttyUSB0,nonblock,b1200,cs7,parenb,waitlock=/var/run/ttyUSB0.lock
On the client side (where the program is, expecting data from ttyUSB0):
sudo socat pty,link=/dev/ttyUSB0,wait-slave tcp:my_server_ip:54321
I face a problem that I can ping to correct IP address, it have no loss. And also I use nmap ping the pi address, and I get it correctly. Then I using VNC viewer to try access to pi, but it always show up "The connection was refused by the host computer"
Did u all have any idea ?
Your problem indicates that your Raspberry Pi was reached by the connection attempt, but that no service was running on the relevant port and hence the connection was refused. I think, this is because the VNC service is not running on your Raspberry Pi.
Update 1
Raspbian now comes with the server by default thanks to a partnership with RealVNC, it just needs to be enabled.
Original
You must enable VNC Server on your Raspberry Pi using terminal
sudo apt-get update
sudo apt-get install realvnc-vnc-server
or you can also enable VNC Server on the command line using the sudo raspi-config command.
Advanced Options->VNC:Yes
Now you can connect to the VNC Server using a application such as VNC Viewer.
I have been having this issue with my Raspberry Pi Zero W even though it worked perfectly beforehand. This page https://www.realvnc.com/en/connect/docs/raspberry-pi.html should help.
I ran vncserver in a ssh window after verifying the interface settings in raspi-config.
It started the VNC Server and gave me the VNC Server catchphrase and the IP address with Port Number as shown in the photo linked below.
vncserver output
After running that command I was able to get the VNC Viewer on my windows machine to connect to the pi.
I then ran sudo systemctl enable vncserver-x11-serviced.service in the ssh window so that it would start automatically on subsequent reboots.
I've had this same problem but found a different reason. I found three ways to get around this error message.
Plug a mouse or keyboard into the Raspberry Pi zero, waking up the screen and the VNC connection.
Wait about 5 - 10 minutes which is the amount of time for the screen saver to kick in which seems to wake up VNC connection. but don't wait to long other wise run this command to get things going via ssh "systemctl start vncserver-x11-serviced.service".
I am hoping the new update they just published will fix this problem. I don't see this as much with the Raspi B3+ as with the Zero H.
The last was plug in both monitor and mouse and that for sure fixes the VNC issues but defeats the headless connection. It seems that running headless and the screen/saver are somehow related but just not smart enough to figure it out.
For people using newer version of Raspberry, VNC option is found under:
Config>Interface Options
pinging to any service will only tells us that whether the server is currently listening on that port or not. It will not tell you the possible result to connection request asked by client.
It seems that, you have installed VNC server but not started it properly. Use this command to start it...
# vncserver start
Also recheck the port number is correct or not.
With the Rasp Pi 4 - had connecting fail after rebooting both the server and client (both Rasp Pi 4s).
Took a while to realize that I have two clients: One named "VNC Client", the other "VNC Viewer for Google Chrome".
The former works, the latter doesn't.
I am trying to configure LIRC to work with my Raspberry 2B and a circuit I build with a transistor and a IR transmitter as explained in this tutorial
After the installation of LIRC, I followed all the steps and I added these two lines in /etc/modules
lirc_dev
lirc_rpi gpio_out_pin=36
Then I typed this in /etc/lirc/hardware.conf
LIRCD_ARGS="--uinput"
LOAD_MODULES=true
DRIVER="default"
DEVICE="/dev/lirc0"
MODULES="lirc_rpi"
LIRCD_CONF=""
LIRCMD_CONF=""
After rebooting, I added the configuration of my Samsung remote (BN59-00516A) to /etc/lirc/lircd.conf
Then I restarted LIRC again but when I run a command to send a IR frequency
irsend SEND_ONCE Samsung_BN59-00865A KEY_POWER
it complains with the following error:
irsend: could not connect to socket
irsend: No such file or directory
I am guessing this is a problem with my device socket, because in the hardware.conf file I set
DEVICE = "/dev/lirc0"
(just because the tutorial states it), but lirc0 file isn't within the folder.
I couldn't find any other question related to this problem and google didn't help me much either. Does anyone have any hint on this?
After googling a lot, I found out an update is needed to have everything working properly. In my case I did:
apt-get update, apt-get upgrade, rpi-update
Also, as pointed out in this other tutorial, depending on the Raspberry firmware, you might need to add this to /boot/config.txt
dtoverlay=lirc-rpi,gpio_in_pin=XX,gpio_out_pin=YY
Substitute X and Y for whatever pins you're using!
I had a similar problem and I solved it with this command:
sudo lircd --device /dev/lirc0
If you set the value of LIRCD_ARGS in /etc/lirc/hardware.conf to "--device /dev/lirc0", it should start lircd appropriately, when /etc/init.d/lirc is started at boot.
you need to run lircd. It will create two files (lircd and lircd.pid) at /var/run/lirc/:
lircd
I got the same error messages. But had all configurations done. The restart of the lirc daemon solved this issue by typing
$ sudo /etc/init.d/lirc restart
I think is useful to say that the gpio_in_pin=XX,gpio_out_pin=YY part of the /etc/modules can be double checked with
dmesg | grep lirc
which results in something like
[ 3.437499] lirc_dev: IR Remote Control driver registered, major 244
[ 5.472916] lirc_rpi: module is from the staging directory, the quality is unknown, you have been warned.
[ 6.621156] lirc_rpi: auto-detected active high receiver on GPIO pin 22
[ 6.622515] lirc_rpi lirc_rpi: lirc_dev: driver lirc_rpi registered at minor = 0
[ 6.622528] lirc_rpi: driver registered!
for /etc/modules containing
lirc_dev
lirc_rpi gpio_in_pin=23 gpio_out_pin=22
I have a Pi that runs hostapd and dhcpd on arch linux to create it's own land with the Pi's (routers) IP being 10.0.0.1. This uses the wlan0 interface and it only serves as a standalone router running a web server.
Once I connect to the Pi, I use 10.0.0.1 to display the web pages, but I want to use a hostname such as firepi. I have tried using dnsmasq, but I haven't been successful. Any help would be greatly appreciated especially if you can give me some detailed examples as I am a novice.
The purpose of this system is that I have created a web app that you can use to ignite fireworks over WiFi at a safe distance. I would just like the convenience of using a hostname instead of the IP address.
I must add that I will more than likely be using an iPhone to connect to the server, should this affect anything.
Not too sure how or why but this is what I did and it is successfully working now, so this is just for future users who may need a similar setup to mine.
First I installed hostapd and dhcpd and made sure they were working. Next I changed '/etc/hostname' to firepi and the '/etc/hosts' and added '10.0.0.1 firepi'. Then I installed dnsmasq, and set the interface to wlan0, and finally added '10.0.0.1 firepi' to '/etc/resolv.conf'.
After a full reboot, I joined the network on my iPhone, navigated to firepi and sure enough, it worked!
Thanks to the other users for their advice and tips.
You can use avahi on Arch as well to resolve your hostname:
sudo pacman -S avahi nss-mdns
Start the avahi daemon:
sudo systemctl enable avahi-daemon.service
sudo systemctl start avahi-daemon.service
Edit /etc/nsswitch.conf
sudo vim /etc/nsswitch.conf
Change the line:
hosts: files myhostname dns
to
hosts: files myhostname mdns_minimal [NOTFOUND=return] dns
Reboot
Note: don't forget to add .local to your hostname.
See also:
http://blog.pixxis.be/post/77285636682/resolve-hostname-with-arch-linux-on-a-raspberry-pi
If you just want to be able to use "firepi" as hostname to connect to it, you can simply add it to your /etc/hosts file using the syntax "IP host".
To make it as easy as possible, run this command as root:
echo "10.0.0.1 firepi" >> /etc/hosts
That'll do the trick.
Can you try avahi ?
sudo apt-get install avahi-daemon and
sudo apt-get install avahi-browse
I've successfully used that on Raspian. Unless you change the hostname using
sudo raspi-config you will access via raspberrypi.local
Note that if you plan to access the RPi from Windows you will need to install Bonjour Service first(if you have iTunes intalled, you might have those, run services.msc and check if the Bonjour Service is started)
Another note: On a friend's iphone I've installed a generic vnc client and had x11vnc running on the RPi and succesfully managed to connect to the RPi (since avahi-daemon was installed)