Homelab, Linux, JS & ABAP (~˘▾˘)~
 

Tag: reverse proxy

Fiori / SAPUI5

[Fiori] Launchpad: Failed to load catalogs

 , , , , , , , , ,

Recently, I was confronted with the “Failed to load catalogs” error message when starting the Fiori Launchpad (/ui2/flp) and navigating to the App Finder.

The system was quite new and the Fiori Customizing was not completely done yet. When opening the Dev Tools, I saw a failed request to

/sap/opu/odata/ui2/page_builder_pers/PageSets('%2FUI2%2FFiori2LaunchpadHome')

Opening this failed request in a new tab results in an HTTP 404 from an Apache web service. So it looked like an Apache was set up as reverse proxy in front of the sap system. I tried to call the PageSets endpoint without providing the key %2FUI2%2FFiori2LaunchpadHome and got an HTTP 200. So in general, Apache was working, and the service endpoint page_builder_pers was responding. Next, I did the same service calls from the gateway client and both calls were working fine. So it looked like Apache was the problem when providing the PageSets key. After a quick search, I found this post on Stack Overflow:

https://stackoverflow.com/questions/37834925/apache-reverse-proxy-blocking-sap-fiori-launchpad-url

So the issue was some (in this case) incorrect decoding of ‘%2F’. After contacting the basis team and adding the proposed Apache configs, the request finally resolved successfully, and the Launchpad was displaying some apps.

Docker, LXC, Nginx

[NGINX] Monitoring Nginx using Netdata

 , , , , , ,

Recently I saw this tutorial about monitoring Nginx with Netdata and tried it by myself. I have running Netdata on my Proxmox Host and Nginx inside LXC. So I could skip step 1 and 2 of the tutorial. Since I’m using the super simple nginx-proxy-manager, which comes as docker deployment, it took me some minutes to figure out, how to enable the Nginx ‘stub_status‘ module (which is step 3 of the tutorial). Here’s what I did.

SSH into the LXC where the Nginx Docker is running. Look up the nginx container name (root_app_1) and open a shell in the running container.

docker ps
docker exec -it root_app_1 /bin/bash

Check if the ‘stub_module‘ is already enabled. The following command should return: with-https_stub_status_module
I got it from here.

nginx -V 2>&1 | grep -o with-https_stub_status_module

Next add a location to the nginx ‘server {}‘ block in the default config, to make it reachable via Netdata. The tutorial goes to ‘/etc/nginx/sites-available/default‘, another tutorial is editing ‘/etc/nginx/nginx.conf‘, but I found the default config in ‘/etc/nginx/conf.d/default.conf’.

nano /etc/nginx/conf.d/default.conf

If nano is not installed (bash: nano: command not found), just install it. Get more information here or here.

apt update 
apt install nano -y

Insert the new location in the server { listen 80; …..} block. In my case I have running Netdata on my Proxmox host, so i added localhost and my Proxmox ip.

  location /nginx_status {
	stub_status;
	allow 192.168.178.100; #only allow requests from pve
	allow 127.0.0.1;	  #only allow requests from localhost
	deny all;		  #deny all other hosts	
  }

Save, exit your docker container and restart it.

docker restart root_app_1

SSH into Proxmox and check with curl, if you able to reach the new nginx location.

For the last step Configure Netdata to Monitor Nginx (step 4) , just follow the Netdata Wiki. Place a new file called nginx.conf on your Netdata host.

nano /etc/netdata/python.d/nginx.conf

Because Netdata is not running local, use ‘remote‘ following the url, instead of local and localhost.

update_every : 10
priority     : 90100

remote:
  url     : 'https://192.168.178.197/nginx_status'

Restart Netdata and your are done.

sudo systemctl restart netdata
Docker, Nginx

[NGINX] Reverse Proxy

 , , , ,

As I installed OnlyOffice to edit Word and Excel files directly from my Nextcloud, I had to setup a reverse proxy because OnlyOffice needs to run on a separate Server/Container and has to be reachable via https. First I tried to setup Nginx manually (way to complicated to handle in my opinion), then I tried Traefik (if you’re running a docker einvironment, I’m sure that’s a good solution) and in the end, I stuck with Nginx Proxy Manager. If you already have docker installed, this is by far the easiest way and also provides an awesome WebUI, where you can manage all your proxy hosts and SSL certificates.

The installation is done in just three simple steps: Set the port fowarding (80 and 443) in your router to your server/container, grab all the files in the doc/example/ folder and run

docker-compose up -d

And it’s done.
Now just enter the WebUI (ip:81) and setup all your routes.