# Exec node + Python3 Script on Ubuntu resulting in \[Errno 13\] Permission denied **URL:** \ **Category:** General\ **Created:** [9 June 2020 01:16 UTC](https://discourse.nodered.org/t/exec-node-python3-script-on-ubuntu-resulting-in-errno-13-permission-denied/28021 "2020-06-09T01:16:47Z")\ **Posts on this page:** 7\ **Page:** 1
**Author:** ![achirife](https://avatars.discourse-cdn.com/v4/letter/a/898d66/32.png) [@achirife](https://discourse.nodered.org/u/achirife)\ **Post date:** [9 June 2020 01:16 UTC](https://discourse.nodered.org/t/exec-node-python3-script-on-ubuntu-resulting-in-errno-13-permission-denied/28021/1 "2020-06-09T01:16:47Z")
Hi all, New to Node-Red and Ubuntu but I was moving fine ... until i crashed! Hope that you can help me clarify an issue that has been torturing me for a couple of days: The Intended Flow that is not working: [Inject node] sends “hello…” string → [Exec node] calls Python3 script and passes the payload as parameter - This returns a JSON string → [Debug node] shows the JSON string returned from Exec node. * * * The issue - Exec node returns permission error: Command failed: python3 /home/alex/ac\_work/python3/p3\_test\_1.py "Parameter-1" python3: can't open file '/home/alex/ac\_work/python3/p3\_test\_1.py': [Errno 13] Permission denied * * * Some facts: 1 - If I go to Terminal and type the command used in the “exec” node, the script runs properly. It takes the parameter and returns the JSON string. No issues. 2 - The directory where the python3 script is at has the following permissions: alex@alex-FX6860:~/ac\_work/python3$ ls -l total 8 -rw-r--r-- 1 root root 14 Jun 8 20:10 nodered\_created\_file2.txt -rwxrwxrw- 1 alex ac\_nodered 422 Jun 8 16:15 p3\_test\_1.py alex@alex-FX6860:~/ac\_work/python3$ 3 - I created a simple output to file using the [File node], and the “nodered\_created\_file2.txt” got created. Notice that it has “root” as both owner and group. 4 - Created a Group called ac\_nodered (users alex and root), and this is the Gropu in the directory where the python script resides. 5 - Environment: Node-Red 1.0.6 running on Ubuntu 18.04.4 LTS, and started from the browser as URL [http://127.0.0.1:1880/](http://127.0.0.1:1880/) Why is that this happens when, it appears that Node-RED is executing as root (all the reach of root), and also, root is one of the users in the group ac\_nodered that has "rwx" in that directory? Any help will be greatly appreciated. Rgds,Alex ---
**Author:** ![Colin](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/colin/32/17040_2.png) [@Colin](https://discourse.nodered.org/u/Colin)\ **Post date:** [9 June 2020 07:56 UTC](https://discourse.nodered.org/t/exec-node-python3-script-on-ubuntu-resulting-in-errno-13-permission-denied/28021/2 "2020-06-09T07:56:40Z")
Do you have a good reason for running as root? This is inherently risky as it gives node-red full access to trash your system in the case of a bug, accident or malicious intent. I would start by fixing that, so it is not running as root (did you see the [recommended Debian/Ubuntu/Pi install script](https://nodered.org/docs/getting-started/raspberrypi)?). Then fix the file permissions in your home folder `sudo chown -R alex:alex ~` and start again. This may not fix the problem but may throw light on what is going on. ---
**Author:** ![achirife](https://avatars.discourse-cdn.com/v4/letter/a/898d66/32.png) [@achirife](https://discourse.nodered.org/u/achirife)\ **Post date:** [9 June 2020 12:54 UTC](https://discourse.nodered.org/t/exec-node-python3-script-on-ubuntu-resulting-in-errno-13-permission-denied/28021/3 "2020-06-09T12:54:35Z")
Hi Colin, thanks for your reply. I don't know why Node-Red is using 'root' user, and it was definitely not my intention. I didn't request that during installation of Node-Red. How can I change the Ubuntu user that is being used by Node-Red to my user "alex"? Thanks! ---
**Author:** ![Colin](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/colin/32/17040_2.png) [@Colin](https://discourse.nodered.org/u/Colin)\ **Post date:** [9 June 2020 14:00 UTC](https://discourse.nodered.org/t/exec-node-python3-script-on-ubuntu-resulting-in-errno-13-permission-denied/28021/4 "2020-06-09T14:00:34Z")
How did you install it and how are you running it? Also please post the startup log you get when you run it. ---
**Author:** ![achirife](https://avatars.discourse-cdn.com/v4/letter/a/898d66/32.png) [@achirife](https://discourse.nodered.org/u/achirife)\ **Post date:** [9 June 2020 18:25 UTC](https://discourse.nodered.org/t/exec-node-python3-script-on-ubuntu-resulting-in-errno-13-permission-denied/28021/5 "2020-06-09T18:25:46Z")
Colin, for a clean start, I exported my flows, reinstalled Node-RED in my Ubuntu machine following [https://nodered.org/docs/getting-started/raspberrypi](https://nodered.org/docs/getting-started/raspberrypi), imported flows again, and now everything works properly. Thank you! ---
**Author:** ![Colin](https://sea2.discourse-cdn.com/flex026/user_avatar/discourse.nodered.org/colin/32/17040_2.png) [@Colin](https://discourse.nodered.org/u/Colin)\ **Post date:** [9 June 2020 20:17 UTC](https://discourse.nodered.org/t/exec-node-python3-script-on-ubuntu-resulting-in-errno-13-permission-denied/28021/6 "2020-06-09T20:17:13Z")
Excellent, glad to be of help. ---
**Author:** ![system](https://us1.discourse-cdn.com/flex026/uploads/nodered/original/1X/d073cd938eafa2e558d7c2cd59003b3ef4963033.png) [@system](https://discourse.nodered.org/u/system)\ **Post date:** [23 June 2020 20:17 UTC](https://discourse.nodered.org/t/exec-node-python3-script-on-ubuntu-resulting-in-errno-13-permission-denied/28021/7 "2020-06-23T20:17:14Z")
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