OpenCPU: how to change the default port? - opencpu

Is there a way to have OpenCPU listening on a port different from :80?
It should be easy using Docker, but I'm running a dedicated Ubuntu machine as recommended here.
ps. I'm only using opencpu-server without opencpu-cache and so without nginx.

It already runs on an additional port 8004 by default. You should be able to changed that in your /etc/apache2/sites-available/opencpu.conf file.

Related

Localhost refused to connect on WSL2 when accessed via https://localhost:8000/ but works when using internal WSL IP adress

What I'm Trying to Achieve
To access localhost from my local machine during the development of a Symfony web app.
My Environment
WSL2 running on Windows 10
Linux, Apache2, MySQL, PHP-7.4 stack (with Xdebug3 intalled)
Debian 10
Symfony 5.4 (although not sure on if relevant to this problem)
Steps I've Taken
Set up WSL2 according to this Microsoft WSL2 tutorial
Set up LAMP stack according to this Digital Ocean tutorial
Set up Symfony according to this Symfony tutorial
Run the following bash script on startup to start my services and set the host to the virtual WSL IP in my xdebug.ini file
#!/bin/sh
REMOTEIP=`cat /etc/resolv.conf | grep nameserver | sed 's/nameserver\s//'`
sed -i -E "s/client_host=[0-9\.]+/client_host=$REMOTEIP/g" /etc/php/7.4/mods-available/xdebug.ini
service php7.4-fpm start
service apache2 start
service mysql start
Run my Symfony project on the development server using symfony serve -d (Symfony then tells me "The Web server is using PHP FPM 7.4.23 https://127.0.0.1:8000")
Go to https://localhost:8000/ in Chrome where the app is running
What I Expect to Happen
My Symfony web app to be running on https://localhost:8000/ when I visit the URL in my Chrome browser
What Actually Happens
I get "This site can't be reached localhost refused to connect." in the Chrome browser
What I've Tried
This used to happen less frequently and I would give my laptop a restart, repeat the process above, and I could connect via https://localhost:8000/. However, it refuses to connect more regularly now (like 8/10 times I start up for the day)
Connecting to https://127.0.0.1:8000 yields the same result.
Connecting to the site using the internal WSL IP address, found using hostname -I and replacing localhost with this IP (still on port 8000). This is an adequate workaround to use my app, however I am unable to interact with my database via MySQL Workbench without having to set up a new connection, therefore a fix where I can use localhost would be very helpful!
(Based off comments) Only ran symfony serve -d without starting apache and PHP services separately - still sometimes allows connections to localhost but sometimes doesn't work.
Conclusion
The behaviour is odd as it works sometimes but other times it doesn't when the exact same steps are carried out. I am unsure where else to look for answers and I can't seem to find anything online with this same problem. Please let me know if any config files, etc would be helpful. Thank you so much for your help! :)
When it's working normally, as you are clearly aware, the "localhost forwarding" feature of WSL2 means that you can access services running inside WSL2 using the "localhost" address of the Windows host.
Sometimes, however, that feature breaks down. This is known to happen when you either:
Hibernate
Have the Windows "Fast Startup" feature enabled (and it is the default). Fast Startup is a pseudo-hibernation which triggers the same problem.
Typically the best solution is to disable Hibernation and Fast Startup. However, if you do need these features, you can reset the WSL localhost feature by:
Exiting any WSL instances
Issuing wsl --shutdown
Restarting your instance
It's my experience that localhost forwarding will work after that. However, if it doesn't, thanks to #lwohlhart in the comments for mentioning that another thing to try is disabling IPv6 on WSL2, since (I believe) there's a possibility that the application is listening on IPv6 while the Windows->WSL2 connection localhost connection is being attempted on IPv6.
You can disable IPv6 on WSL2 per this Github comment by creating or editing .wslconfig in your Windows user profile directory with the following:
[wsl2]
kernelCommandLine=ipv6.disable=1
A wsl --shutdown and restart will be necessary to complete the changes.
If you find that this works, it may be possible to solve the issue by making sure to either use the IPv4 (127.0.0.1) or IPv6 (::1) address specifically in place of localhost on the Windows side, or by configuring the service to listen on both addresses.
Try to run command netstat -nltp. It shows active addresses and ports. Your nginx process should be run at 0.0.0.0:8000. 0.0.0.0 means the nginx process is available from anywhere.
If your nginx process is ran by any specific ip address, you should access it by that ip address, e.g http://192.168.4.2:8000.

Is there a possibility to access a docker-compose container from another machine inside the local network?

I'm using WSL2 Ubuntu with Docker CE and Docker-Compose.
I want to access the containers I'm running (mostly Apache/MySQL/Wordpress containers) from my local network (sometimes same, sometimes other machines).
For example:
PC1: 192.168.178.20
PC2: 192.168.178.21
On PC1 is Windows + WSL2-Ubuntu with all the docker containers.
I want to access the containers from the Windows-Browser (Chrome) but also from the browser from PC2 (also Chrome, for mac).
Is this even possible? If yes, how?
I got webpack to work with hot reload from WSL2 but this seems very hard and I don't know where to start.
Is it possible to add DNS-Names for specific containers in my router? for example if you call "example.test" my router forwards to the IP from the Docker-Box?
There are a couple of solutions, some better than others.
Find the port number that your container is MAPPED to your host machine (PC1) and make sure you can browse that way. Then take the same URL to PC2 and try it out and see if it works. Make sure you are using the Fully Qualified Domain Name or IP address so it is resolved to find PC1.
Find the port number that your container is EXPOSED to your host machine (PC1) and make sure you can browse that way. Repeat the process as above.
Use a reverse proxy. I am biased and will say to use Traefik because of its relative simplicity (compared to nginx) to configure. It is just another container. It uses RULES (combination of URL Header, Port Number, Path, etc.) to route incoming connections to services/containers. In your case you will create a rule of URL Header (webapp1.corp.com) and port number (80) and route it to a specific container you have running. Then from either computer browser enter http://webapp1.corp.com the connection will be routed to the specific container. This is a very simplistic answer that is more complicated but you should get the gist.
You mentioned you are running multiple containers, so I recommend you use docker-compose if you aren't already using it.

Localhost to local network port redirection on Windows

I have a server that listen on http://localhost:8001 and I want to make it available in the local network. Unfortunately I don't have access to the code and can't modify the above. It doesn't listen to requests from outside the network on port 8001.
I want to make it both available in the local network and change the port to 9001. Is there some tool or way to use OS functionality to solve this?
It's a Windows computer and I don't have admin rights.
Edit:
I noticed both python -m SimpleHTTPServer and http-serv on node works if I use 0.0.0.0 as the address but I don't have the power to modify this program so I wanted some way to redirect the calls in a bidirectional way
Edit2:
It's a OWIN Selfhosted .NET Framework Application.
Simply using your hostname should be enough.
You only need a reverse proxy in order to change the port.
This is easy enough with a caddyfile:
caddy reverse-proxy --from :9001 --to 127.0.0.1:8001
And a caddy Windows release (like caddy_2.0.0_windows_amd64.zip) does not require any administration/elevated privilege: just use the caddy.exe. That is it. No setup, no installation, no registry modification.
Then:
https://<yourHostname>:9001

Unable to access MongoDB within a container within a Docker Machine instance from Windows

I am running Windows 7 on my desktop at work and I am signed in to a regular user account on the VPN. To develop software, we are to normally open a Dev VM and work from in there however recently I've been assigned a task to research Docker and Mongo DB. I have very limited access to what I can install on the main machine.
Here lies my problem:
Is it possible for me to connect to a MongoDB instance inside a container inside the docker machine from Windows and make changes? I would ideally like to use a GUI tool such as Mongo Management Studio to make changes to a Mongo database within a container.
By inspecting the Mongo container, it has the ports listed as: 0.0.0.0:32768 -> 27017/tcp
and docker-machine ip (vm name) returns 192.168.99.111.
I have commented out the 127.0.0.1 binding host ip within the mongod.conf file also.
From what I have researched so far, most users resolve their problem by connecting to their docker-machine IP with the port they've set with -p or been given with -P. Unfortunately for me, trying to connect with 192.168.99.111:32768 does not work.
I am pretty stumped and quite new to this environment. I am able to get inside the container with bash and manipulate the database there however I'm wondering if I can do this within Windows.
Thank you if anyone can help.
After reading Smutje's advice to ping the VM IP and testing it out to no avail, I attempted to find a pingable IP which would hopefully move me closer to my goal.
By doing "ifconfig" within the Boot2Docker VM (but not inside the container), I was able to locate another IP listed under eth0. This IP looks something like 134.36.xxx.xxx to me and is pingable. With the Mongo container running I can now access the database from within Mongo Management Studio by connecting to 134.36.xxx.xxx:32768 and manipulate the data from there.
If you have the option of choosing the operating system for your dev VM, go with Ubuntu and setup docker with all of the the containers you want to test on that. Either way, you will need to have a VM for testing docker on windows since it uses VirtualBox if i'm not mistaken. Instead, setup an Ubuntu VM and do all of your testing on that.

xampp not responding to external request

i am trying to run xampp on the internal network but it is not responding
could anyone help me with it
Here are things you can check:
Is it running at all? You might have some other application running on port 80 (default if you haven't changed anything)
Can you access it on the same machine it's running? Open your browser and go to http://localhost/ - if it works, then it's a communication issue between the machines
Can you see anything in the logs?
Do you have any firewall running on the machine running XAMPP? If so, turn it off temporarily and see if it works - you should configure it properly and configure it afterwards
You should check the FAQs:
depending on the OS you are running it on.

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