I'm using Fabric 1.6.0 on OS X 10.8.2, running commands on a remote host on Ubuntu Lucid 10.04.
On the server, I can run sudo /etc/init.d/celeryd restart to restart the Celery service.
I pass the same command through fabric using:
#task
def restart():
run('sudo /etc/init.d/celeryd restart')
Or
#task
def restart2():
sudo('/etc/init.d/celeryd restart')
Or use the command line form fab <task_that_sets_env.host> -- sudo /etc/init.d/celeryd restart
The command always fails silently - meaning that fabric returns no errors, but celeryd reports that it's not running.
I'm tearing my hair out here! There's nothing relevant in the Celery log file, and AFAIK Fabric should just pass the commands straight through.
Maybe I'm pretty late to the party, and you can downvote me if this doesnt work, but I've had similar problems running other programs in /etc/init.d with fabric. My solution (works with tomcat and mysql) is to add pty=False
#task
def restart():
sudo('/etc/init.d/celeryd restart', pty=False)
Theres documentation on the option here:
http://docs.fabfile.org/en/1.7/api/core/operations.html#fabric.operations.run
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.
Which config files could disable the automatically starting ssh server, so a headless connect becomes impossible?
I need to know the config files that might interfere with the ssh server to normally start up at boot.
I believe that you are looking for the following commands (assuming you are running the last version of raspbian):
sudo systemctl stop sshd
sudo systemctl disable sshd
sudo systemctl mask sshd
stop Basically stops the service immediately. disable disables the service from starting at bootup. Additionally, mask will make it impossible to load the service.
Digging deeper into what each command does, on modern linux distributions there are configuration files for each service called unit files. They are stored (usually) in /usr/lib/systemd. These are basically the evolution of scripts to start services.
the stop command just calls the sshd.service unit file with a stop parameter, in order to shut down the server.
the disable (or enable) command removes(or creates) a symlink of the unit file in a directory where systemd looks into when booting services (usually, /etc/systemd/system).
systemctl mask creates a symlink to /dev/null instead of the unit file. That way the service cant be loaded.
I've got problem with completing pgadmin4 installation thru sudo /usr/pgadmin4/bin/setup-web.sh command.
During this process instalator does not recognizing that Apache is running and asks me if I want to start it:
The Apache web server is not running. We can enable and start the web server for you to finish pgAdmin 4 installation. Continue (y/n)? y
Then it just spits some errors:
Too few arguments.
Error enabling . Please check the systemd logs
Too few arguments.
Error starting . Please check the systemd logs
So far I havn't found where the logs are stored.
About my apache, I am quite sure that my server is running, because I can connect to it through browser, phpmyadmin is working properly, and service apache2 status returns * apache2 is running. By my understanding apache2 is just fancy word for httpd service, and there is no other service called simply apache.
PostgreSQL seems to work properly from command line, haven't tested if I can connect to it yet, but this shouldn't be the case right?
I am using
**PostgreSQL:** 12.5 (Ubuntu 12.5-0ubuntu0.20.04.1)
**Ubuntu:** Ubuntu 20.04 LTS
**Server:** Apache/2.4.41 (Ubuntu)
I had the same issue for Debian 10 and Ubuntu 20. The /usr/pgadmin4/bin/setup-web.sh script is using 'uname -a' which doesn't contain "Debian" identifier in the return string. Updating this to read /proc/version will allow APACHE to be specified as the Debian variant of apache2.
Change:
UNAME=$(uname -a)
To:
UNAME=$(cat /proc/version)
I had a similar problem with Ubuntu running inside WSL 2. Managed to resolve it by modifying the /usr/pgadmin4/bin/setup-web.sh script. I moved these lines outside of the conditional:
IS_DEBIAN=1
APACHE=apache2
This allowed the installation to progress beyond the Too few arguments. error. There was still an error however:
System has not been booted with systemd as init system (PID 1). Can't operate.
Error restarting apache2. Please check the systemd logs
I resolved this by running:
sudo service apache2 restart
After this I tried bringing up the admin page by visiting http://127.0.0.1/pgadmin4 from the Windows host. This still didn't work, and had to connect using the Ubuntu machine's ip address (you can find it out via ifconfig) which finally allowed me to see the login page.
Getting access denied error while running the systemctl command in a pod.
Whenever try to start any service, for example, MySQL or tomcat server in a pod, it gives access denied error.
Is there any way by which I can run systemctl within a pod.
This is a problem related to Docker, not Kubernetes.
According to the page Run multiple services in a container in docker docs:
It is generally recommended that you separate areas of concern by
using one service per container
However if you really want to use a process manager, you can try supervisord, which allows you to use supervisorctl commands, similar to systemctl. The page above explains how to do that:
Here is an example Dockerfile using this approach, that assumes the
pre-written supervisord.conf, my_first_process, and my_second_process
files all exist in the same directory as your Dockerfile.
FROM ubuntu:latest
RUN apt-get update && apt-get install -y supervisor
RUN mkdir -p /var/log/supervisor
COPY supervisord.conf /etc/supervisor/conf.d/supervisord.conf
COPY my_first_process my_first_process
COPY my_second_process my_second_process
CMD ["/usr/bin/supervisord"]
That's a rather short question. The 'systemctl' command does try to talk to the systemd daemon which is not running in a pod by default (it could however). Running multiple services is yet another question about service management. It both cases it could help to use a tool like the docker-systemctl-replacement overwriting /usr/bin/systemctl and registering it as the init-CMD of the container.
I'm running docker container in OSX using boot2docker. It is a latest Ubuntu image with mongo installed using official way from package mongodb-org.
I can perfectly run mongod from command line, but can't run it as a service.
When I'm trying to do sudo service mongod start it returns
Rather than invoking init scripts through /etc/init.d, use the service(8)
utility, e.g. service mongod start
Since the script you are attempting to invoke has been converted to an
Upstart job, you may also use the start(8) utility, e.g. start mongod
I have tried to do start mongod which doesn't have any output. I have tried everything I found in Google, but no luck.
Meanwhile, I have tried to install MySQL using apt-get and I can perfectly run it as a service.
Also I have tried to install Mongo from Ubuntu's mongodb package which is a older version. Also no problem to run it as a service.
I suspect that there is something wrong with /etc/init.d/mongod script, but don't know exactly what.
Apprieciate any help.
The init-related commands on the Docker Ubuntu image are dummied out / not working because Upstart (/sbin/init) is not the first process started on the machine.
In general, any service which initializes using Upstart will not run properly in a Docker container unless you start the container with /sbin/init (you probably have to be using the ubuntu-upstart image, and make a bunch of tweaks to it too.)
If you really needed to do it this way, write a traditional init script for mongo and insert it using update-rc.d. Then, starting it with /sbin/service should work.
Why not just have the Dockerimage run mongod instead of init/shell/etc? "One process per container", right?
Use a Dockerfile to create your image, and set the CMD to:
CMD ["/usr/bin/mongod", "-f", "/etc/mongod.conf"]