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I've tried doing the NTP, but this pi travels from various places at various times a month and doesn't always have the proper access for NTP. Is there a way I can have it sync with Colorado's atomic clock during its booting sequence?
I currently running Raspian OS on the 512 version of Model B
There are three options by which you can sync your raspberry pi time.
Solution 1: you can use RTC or any hardware clock and you can sync your RPi time with the clock.
Solution 2: Use a GPS module and sync the time with that.This will not work properly until your get you GPS locked.
Solution 3: You can use NTP server to sync your Raspberry Pi time. At this case you need your RPi connected to Internet.
First install ntp to your Pi.
$ sudo apt-get install ntpdate
Then reconfigure your tzdata with your location and local time by typing
$ sudo dpkg-reconfigure tzdata
Now you need to run this following commands to sync your RPi time with NTP server.
$ sudo service ntp stop
$ sudo ntpdate -s time.nist.gov
$ sudo service ntp start`
If you want to sync your time with web on start/reboot, you have to add it in your cronjob.
Assuming I have understand the question correctly – if syncing manually to the internet time whenever online and then let the local RTC do its job when offline is good enough, then you should use an external RTC module, like this one (or this one) and follow the instructions on how to configure the Linux to get the time locally instead from internet. On the adafruit's 'Set RTC Time' page it says "Once the time is correct [i.e. from the internet] (...), run sudo hwclock -w to write the system time to the RTC", so I assume this command can be used later at anytime to sync again the local clock with the defined NTP clock (but cannot check this for myself, as I don't have a hardware RTC yet).
As for the timezone, if using Raspbian this can be set via sudo raspi-config > Internationalisation Options (when in command line mode) or via Menu > Preferences > Raspberry Pi Configuration > Localisation (when in desktop mode).
I was stuck on this for a while. Was able to sync to the NTP server but was always 9 hours ahead. Fixed it by forcing a timezone change to Pacific.
$ sudo dpkg-reconfigure tzdata
Related
I am attempting to debug some C# / .NET 5 code in WSL 2 with Ubuntu on Windows. I have WSL 2 setup with Windows 10 and want to test out creating a Systemd service. Unfortunately, it appears Systemd is not enabled with WSL 2 by default, even though a standard Ubuntu install does have it enabled by default. Is there any way to get Systemd enabled in WSL 2?
Note: See footnote at bottom of this answer for background on this Community Wiki.
There are several possible paths to enabling Systemd on WSL2 (but not WSL1). These are summarized here, with more detail provided below.
Option 1: Upgrade WSL to the latest application release (if supported by your system) and opt-in to the Systemd feature
Option 2: Run a Systemd-helper script designed for WSL2
Option 3: Manually run Systemd in its own namespace
And while not part of this question, for those simply looking to run certain applications that require Systemd, there are alternatives:
On WSL1 and WSL2:
Alternative 1: SysVInit scripts (e.g. sudo service <service_name> start) where available
Alternative 2: Manually configuring and running the service
On WSL2-only:
Alternative 3: Docker
Should you enable Systemd in WSL?
First, consider whether you should or need to enable Systemd in WSL. Enabling Systemd will automatically start a number of background services and tasks that you really may not need under WSL. As a result, it will also increase WSL startup times, although the impact will be dependent on your system. Check the Alternatives section below to see if there may be a better option that fits your needs. For example, the service command may do what you need without any additional effort.
More detail on each answer:
Option 1: Upgrade WSL to the latest application release (if supported by your system) and opt-in to the Systemd feature
Microsoft has now integrated Systemd support in the WSL2 application release (as opposed to the older "Windows feature" implementation).
Starting with WSL Application Release 1.0.0, this feature is available on both Windows 10 and Windows 11. Windows 10 users do need to be on UBR (update build revision) 2311 or later. The UBR is the last 4 digits of your full Windows build number (e.g. 10.0.19045.2311 for Windows 10 22H2). 2311 is installed with KB5020030, an optional Preview update, although if you are reading this later, it will likely be a later (non-Preview) monthly servicing update.
If you are on a supported Windows release, the WSL application with Systemd support can be installed:
Through the Microsoft Store (as "Windows Subsystem for Linux").
Or from the Releases page in the Github repo. To install a release manually:
Reboot (to make sure that WSL is not in use at all). A simple wsl --shutdown may work, but often will not.
Download the 1.0.0 (or later) release from the link above.
Start an Administrator PowerShell and:
Add-AppxPackage <path.to>/Microsoft.WSL_1.0.0.0_x64_ARM64.msixbundle
wsl --version # to confirm
To enable, start your Ubuntu (or other Systemd) distribution under WSL (typically just wsl ~ will work).
sudo -e /etc/wsl.conf
Add the following:
[boot]
systemd=true
Exit Ubuntu and again:
wsl --shutdown
Then restart Ubuntu.
sudo systemctl status
... should show your Systemd services.
Option 2: Run a Systemd-helper script designed for WSL2
There are a number of Systemd-enablement scripts available from various sources. Given the complexities involved in running Systemd under WSL, it is recommended that you:
Use one that is actively maintained
Attempt to understand, as much as possible, how they operate, and how they may impact other features and applications in your distribution(s) under WSL
When asking questions here or on any other site, disclose in the question which script you are using so that others can attempt to understand and/or reproduce your issue in the proper context
Several of the more popular projects that enable Systemd under WSL2 are:
Genie: 1.8k stars, last commit September, 2022
Distrod: 1.4k stars, last commit July 2022
WSL2-Hacks: 1.1k stars, mostly instructional, with a supporting script example. Last commit January, 2022
At the core, all of them operate on the same principles covered in the next option ...
Option 3: Manually run Systemd in its own namespace
One of the main issues with running Systemd in earlier versions of WSL is that both inits need to be PID 1. To get around this, it is possible to create a new namespace or container where Systemd can run as PID 1.
To see how this is done (at a very basic level):
Run:
sudo -b unshare --pid --fork --mount-proc /lib/systemd/systemd --system-unit=basic.target
This starts Systemd in a new namespace with its own PID mapping. Inside that namespace, Systemd will be PID1 (as it must, to function) and own all other processes. However, the "real" PID mapping still exists outside that namespace.
Note that this is a "bare minimum" command-line for starting Systemd. It will not have support for, at least:
Windows Interop (the ability to run Windows .exe)
The Windows PATH (which isn't necessary without Windows Interop anyway)
WSLg
The scripts and projects listed above do extra work to get these things working as well.
Wait a few seconds for Systemd to start up, then:
sudo -E nsenter --all -t $(pgrep -xo systemd) runuser -P -l $USER -c "exec $SHELL"
This enters the namespace, and you can now use ps -efH to see that systemd is running as PID 1 in that namespace.
At this point, you should be able to run systemctl.
And after proving to yourself that it's possible, it is recommended that you exit all WSL instances completely, then doing wsl --shutdown. Otherwise, some things will be "broken" until you do. They can likely be "fixed", but that's beyond the scope this answer. If you are interested, please refer to the projects listed above to see how they handle these situations.
Alternative 1: SysVInit scripts (e.g. sudo service <service_name> start) where available
In Ubuntu, Debian, and some other distributions on WSL, many of the common system services still have the "old" init.d scripts available to be used in place of systemctl with Systemd units. You can see these by using ls /etc/init.d/.
So, for example, you can start ssh with sudo service ssh start, and it will run the /etc/init.d/ssh script with the start argument.
Even some non-default packages such as MySql/MariaDB will install both the Systemd unit files and the old init.d scripts, so you can still use the service command for them as well.
On the hand, some packages, like Elasticsearch, only install Systemd units. And some distributions only provide Systemd units for most (if not all) packages in their repositories.
Alternative 2: Manually configuring and running the service
For those services that don't have a init-script equivalent, it can be possible to run them "manually".
For simplicity, let's assume that the ssh init.d script wasn't available.
In this case, the "answer" is to figure out what the Systemd unit files are doing and attempt to replicate that manually. This can vary widely in complexity. But I'd start with looking at the Systemd unit file that you are trying to run:
less /lib/systemd/system/ssh.service
# Trimmed
[Service]
EnvironmentFile=-/etc/default/ssh
ExecStartPre=/usr/sbin/sshd -t
ExecStart=/usr/sbin/sshd -D $SSHD_OPTS
RuntimeDirectory=sshd
RuntimeDirectoryMode=0755
Some of the less relevant lines have been trimmed to make it easier to parse, but you can man systemd.exec, man systemd.service, and others to see what most of the options do.
In this case, when you sudo systemctl start ssh, it:
Reads environment variables (the $SSHD_OPTS) from /etc/default/ssh
Tests the config, exits if there is a failure
Makes sure the RuntimeDirectory exists with the specified permissions. This translates to /run/sshd (from man systemd.exec). This also removes the runtime directory when you stop the service.
Runs /usr/sbin/sshd with options
So, if you don't have any environment-based config, you could just set up a script to:
Make sure the runtime directory exists. Note that, since it is in /run, which is a tmpfs mount, it will be deleted after every restart of the WSL instance.
Set the permissions to 0755
Start /usr/sbin/sshd as root
... And you would have done the same thing manually without Systemd.
Again, this is probably the simplest example. You might have much more to work through for more complex tasks.
Alternative 3: Docker
Many packages/services are available as Docker images. Docker typically runs very well under Ubuntu on WSL2 (specifically WSL2; it will not run on WSL1). If there's not a SysVinit "service" script for the service you are trying to start, there may very well be a Docker image available that runs in a containerized environment.
Example: Elasticsearch, as in this question.
Bonus #1: Doesn't interfere with other packages already installed (no dependency issues).
Bonus #2: The Docker images themselves pretty much never use Systemd, so you can often inspect the Dockerfile to see how the service is started without Systemd. For more information see the next option - "The manual way."
Microsoft recommends Docker Desktop for Windows for running Docker containers under WSL2.
Footnote This answer is being posted as a Community Wiki because it can apply to multiple Stack Overflow questions. It is originally based on answers to this Ask Ubuntu question. However, it is hoped that this wiki-answer can be continuously updated by the community as Systemd evolves on WSL.
This question has been chosen since:
It appears to be the most canonical, straightforward, "How do I enable Systemd on WSL?" question.
It is on-topic, as *creating Systemd services is (or at least can-be) unique to programming.
EDIT: This problem is solved! the problem was a script running on the pi, which occupied the SCL pin (in my case a script listening for a shutdown button). So it was not able to read the rtc.
I'm currently following this tutorial to connect my Raspberry Pi Zero W running Jessie Lite to the RTC DS1307.
The rtc is being recognized when running sudo i2cdetect -y 1 with "UU", so everything fine until this point.
But when entering sudo hwclock -D -r I'm getting an error:
Does anybody have any experience or hints with this error? I was researching for 1 1/2 day now, but could not find a working solution. Any help is appreciated.
Back then I was not able to answer my own question. I have already edited the main post, but to close this question:
This problem is solved! the problem was a script running on the pi, which occupied the SCL pin (in my case a script listening for a shutdown button). So it was not able to read the rtc.
I bought a Raspberry Pi 3 Model B, a microstack baseboard and a microstack GPS.
I followed the instructions written in the official documentation but I can't connect to the GPS.
Basically, the GPS led flashes so it means it has find a gps fix, but I can't see any data from the PI.
For example, if I try
cat /dev/ttyAMA0
I get always nothing. I already used raspi-config to disable kernel serial and to enable i2c and spi.
Also if I try
stty -F /dev/ttyAMA0 ispeed 4800 && cat </dev/ttyAMA0"
I get an error.
Anyone has any advice, please?
Or maybe these modules are not compatible with Pi 3?
Thanks a lot!
It's hard telling what has been done, or not done. The 'official' documentation from Microstack provides two methods of setting up the serial port. It then continues with
Automatically Starting gpsd
To automatically start the gps service when the Raspberry Pi® boots, reconfigure the GPS
daemon by typing into a terminal
sudo dpkg-reconfigure gpsd
● Choose <yes> when asked if you want to start gpsd automatically.
● Choose <no> when asked “should gpsd handle attached USB GPS
receivers automatically” .
● When asked which “Device the GPS receiver is attached to” , enter
/dev/ttyAMA0 .
● Accept the defaults for other options.
If you have configured your serial port as per instructions and configured gpsd to automagically start and pick up the device you have just setup, ...then, since the gpsd is handling the device (right?), the device will be busy and the command cat /dev/ttyAMA0 should return cat: /dev/ttyAMA0: Device or resource busy...but, it did not.
Either the serial is not configured as per instructions, or the gpsd is not running and picking up the device, or both.
The goal is not to cat your gps data, but the cat not returning an error indicates something is amiss.
Typically, it's just a typo. But it can be from skipping a step in the process, or mixing instructions from various sources so that the left hand doesn't know what the right hand has done.
Try:
sudo killall gpsd if it returns gpsd: no process found that answers one question.
If it returns with no error, follow it up with cat /dev/ttyAMA0. If it returns nothing, the direction you should look is your serial port configuration.
If sudo dpkg-reconfigure gpsd is not allowing you to reconfigure (I thought it was just me) you can modify the configuration of gpsd by using your favourite editor, e.g. sudo nano /etc/default/gpsd and entering something like:
# Default settings for the gpsd init script and the hotplug wrapper.
# Start the gpsd daemon automatically at boot time
START_DAEMON="true"
# Use USB hotplugging to add new USB devices automatically to the daemon
USBAUTO="false"
# Devices gpsd should collect to at boot time.
# They need to be read/writeable, either by user gpsd or the group dialout.
DEVICES="/dev/ttyAMA0"
# Other options you want to pass to gpsd
GPSD_OPTIONS="-n -G"
You may find the -n and -G useful. Save and restart.
I finally found a solution:
On the Pi 3, there are more steps to use serial, you have to disable the BT.
Edit config file:
sudo nano /boot/config.txt
Add this at the bottom:
dtoverlay=pi3-disable-bt-overlay
Then run this:
sudo systemctl disable hciuart
This article was very usefull for me
http://spellfoundry.com/2016/05/29/configuring-gpio-serial-port-raspbian-jessie-including-pi-3/#comment-67160
and i recommand you to read it
Now on RPI3 the Serial port
ttyAMA0 is used by BlueTooth
ttySO refers to the GPIO
The Alias Serial0 refers to the GPIO both on RPI2 and RPI3.
So :
after a reinstallation of Jessie with a recent version to be sure all is clean
as usual
$ sudo apt-get update
$ sudo apt-get upgrade
$ sudo raspi-config
go to Advanced options : Would you like a login shell to be accessible over serial? response "yes" (not as in the microstack datasheet )
$ sudo apt-get install python3-microstacknode
To install the gpsd standard tools
$ sudo apt-get install gpsd gpsd-clients python-gps
edit GPSD by
$ sudo nano /etc/default/gpsd
and put the options :
START_DAEMON="true"
USBAUTO="false"
DEVICES="/dev/serial0"
GPSD_OPTIONS="-n -G"
equally
$ sudo nano /boot/cmdline.txt
remove
console=serial0,115200
and save
$ sudo nano /boot/config.txt
you must have at the end
enable_uart=1
Disable the console by
$ sudo systemctl stop serial-getty#ttyS0.service
$ sudo systemctl disable serial-getty#ttyS0.service
i have equally done $ sudo chmod 775 ../../dev/ttySO ( i dont know if it is really necessary )
and obviously a reboot
and miracle the gps works with
cgps -s
NB: you must have a fix on the GPS ( the red led flashes )
jpherrenknecht
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
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I would like to ask you if there is any way to start raspberry pi (using Raspbian) without login and password and to move directly to the GUI. Like Windows for example.
Raspbian Wheezy:
Following was taken from eLinux.org RPi Debian Auto Login page:
Auto Login:
In Terminal:
sudo nano /etc/inittab
Scroll down to:
1:2345:respawn:/sbin/getty 115200 tty1
and change to
#1:2345:respawn:/sbin/getty 115200 tty1
Under that line add:
1:2345:respawn:/bin/login -f pi tty1 </dev/tty1 >/dev/tty1 2>&1
Ctrl+X to exit, Y to save followed by enter twice
Auto StartX (Run LXDE):
In Terminal:
sudo nano /etc/rc.local
Scroll to the bottom and add the following above exit 0:
su -l pi -c startx
Raspbian Jessie:
Use raspi-config. If, for some magic reason this tool is not present on your system, install it:
sudo apt-get install raspi-config
Hard way:
Link. Link.
UPDATE 2019.05
In recent distro there's a simpler way to fix this:
At command prompt, type sudo raspi-config, then:
select option 3 in menu (Boot Options)
select option B1 (Desktopp/CLI)
select option B2 (Console Autologin)
Hit OK, exit all the way and restart.
Update 2019.05 credit belongs to Hasan A Yousef.