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+date = 2022-11-11
+title = "Fixing Permission Errors in /var/lib/nginx"
+description = "A quick fix for Nginx permission errors on the tmp directory."
++++
+
+*This is a brief post so that I personally remember the solution as it has 
+occurred multiple times for me.*
+
+## The Problem
+
+After migrating to a new server OS, I started receiving quite a few permission 
+errors like the one below. These popped up for various different websites I'm 
+serving via Nginx on this server, but did not prevent the website from loading.
+
+I found the errors in the standard log file:
+
+```sh
+cat /var/log/nginx/error.log
+```
+
+```sh
+2022/11/11 11:30:34 [crit] 8970#8970: *10 open() "/var/lib/nginx/tmp/proxy/3/00/0000000003" failed (13: Permission denied) while reading upstream, client: 169.150.203.10, server: cyberchef.example.com, request: "GET /assets/main.css HTTP/2.0", upstream: "http://127.0.0.1:8111/assets/main.css", host: "cyberchef.example.com", referrer: "https://cyberchef.example.com/"
+```
+
+You can see that the error is `13: Permission denied` and it occurs in the 
+`/var/lib/nginx/tmp/` directory. In my case, I had thousands of errors where 
+Nginx was denied permission to read/write files in this directory.
+
+So how do I fix it?
+
+## The Solution
+
+In order to resolve the issue, I had to ensure the `/var/lib/nginx` 
+directory is owned by Nginx. Mine was owned by the `www` user and Nginx was not 
+able to read or write files within that directory. This prevented Nginx from 
+caching temporary files.
+
+```sh
+# Alpine Linux
+doas chown -R nginx:nginx /var/lib/nginx
+
+# Other Distros
+sudo chown -R nginx:nginx /var/lib/nginx
+```
+
+You *may* also be able to change the `proxy_temp_path` in your Nginx config, but 
+I did not try this. Here's a suggestion I found online that may work if the 
+above solution does not:
+
+```sh
+nano /etc/nginx/http.d/example.com.conf
+```
+
+```conf
+server {
+  ...
+
+  # Set the proxy_temp_path to your preference, make sure it's owned by the 
+  # `nginx` user
+  proxy_temp_path /tmp;
+
+  ...
+}
+```
+
+Finally, restart Nginx and your server should be able to cache temporary files 
+again.
+
+```sh
+# Alpine Linux (OpenRC)
+doas rc-service nginx restart
+
+# Other Distros (systemd)
+sudo systemctl restart nginx
+```