[GH-ISSUE #735 ] [Bug]: X1C Virtual Printer not accepting Sends #492

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@VREmma commented on GitHub (Mar 17, 2026):

Yes, I want to review them so I can name them correctly. I usually print from queue, and this was working fine until my A1's memory card slot died last night, so I started moving it workflow over to the X1C...

@VREmma commented on GitHub (Mar 17, 2026): Yes, I want to review them so I can name them correctly. I usually print from queue, and this was working fine until my A1's memory card slot died last night, so I started moving it workflow over to the X1C...

BreizhHardware commented

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@maziggy commented on GitHub (Mar 17, 2026):

Now I also got it. Was on the wrong path. Sorry for that. After the 25th ticket I'm seeing bubbles :)

@maziggy commented on GitHub (Mar 17, 2026): Now I also got it. Was on the wrong path. Sorry for that. After the 25th ticket I'm seeing bubbles :)

BreizhHardware commented

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@maziggy commented on GitHub (Mar 17, 2026):

You're right, the bug only affected the X1C.

Available in branch dev and available with the next release or daily build.

@maziggy commented on GitHub (Mar 17, 2026): You're right, the bug only affected the X1C. Available in branch dev and available with the next release or daily build.

BreizhHardware commented

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@VREmma commented on GitHub (Mar 17, 2026):

(venv) bambuddy@bambuddy:/bambuddy$ git pull
Already up to date.
(venv) bambuddy@bambuddy:/bambuddy$ git status
On branch dev
Your branch is up to date with 'origin/dev'.

nothing to commit, working tree clean
(venv) bambuddy@bambuddy:~/bambuddy$

But its still showing the same error when sending to the X1C... Verified in the Virtual Printers that its setup to the new code...

@VREmma commented on GitHub (Mar 17, 2026): > (venv) bambuddy@bambuddy:~/bambuddy$ git pull > Already up to date. > (venv) bambuddy@bambuddy:~/bambuddy$ git status > On branch dev > Your branch is up to date with 'origin/dev'. > > nothing to commit, working tree clean > (venv) bambuddy@bambuddy:~/bambuddy$ But its still showing the same error when sending to the X1C... Verified in the Virtual Printers that its setup to the new code... <img width="1263" height="741" alt="Image" src="https://github.com/user-attachments/assets/3c840fe7-a5e1-4381-a231-4f71ada3f3c6" />

BreizhHardware commented

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@maziggy commented on GitHub (Mar 17, 2026):

No wait....a git pull didn't show any new files? That cannot be. If you do a git pull you should see latest commit

commit 6be5fa6632 (HEAD -> dev, origin/dev)
Author: maziggy mz@v8w.de
Date: Tue Mar 17 16:40:16 2026 +0100

  [Fix] Camera window overlapping modals (#738)

  Floating camera viewer used z-50, same as all modals, causing it to
  render on top of dialogs like Assign Spool. Lowered to z-40 so modals
  always stack above the camera window.

when doing a "git log".

@maziggy commented on GitHub (Mar 17, 2026): No wait....a git pull didn't show any new files? That cannot be. If you do a git pull you should see latest commit commit 6be5fa6632bc214d9aa83bf39252e904faafc724 (HEAD -> dev, origin/dev) Author: maziggy <mz@v8w.de> Date: Tue Mar 17 16:40:16 2026 +0100 [Fix] Camera window overlapping modals (#738) Floating camera viewer used z-50, same as all modals, causing it to render on top of dialogs like Assign Spool. Lowered to z-40 so modals always stack above the camera window. when doing a "git log".

BreizhHardware commented

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@VREmma commented on GitHub (Mar 17, 2026):

@VREmma commented on GitHub (Mar 17, 2026): <img width="797" height="487" alt="Image" src="https://github.com/user-attachments/assets/7e4d4b54-a6f1-4e13-839f-66a893abc1ba" />

BreizhHardware commented

bambuddy-support-20260317-110805.zip

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@VREmma commented on GitHub (Mar 17, 2026):

@VREmma commented on GitHub (Mar 17, 2026): [bambuddy-support-20260317-110805.zip](https://github.com/user-attachments/files/26059940/bambuddy-support-20260317-110805.zip)

BreizhHardware commented

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@maziggy commented on GitHub (Mar 17, 2026):

Every time you are trying to send the file it shows

2026-03-16 22:01:24,215 INFO [backend.app.services.virtual_printer.ftp_server] FTP -> [IP]: 530 Login incorrect
2026-03-16 22:01:24,215 WARNING [backend.app.services.virtual_printer.ftp_server] FTP failed login from [IP]
2026-03-16 22:01:24,216 INFO [backend.app.services.virtual_printer.ftp_server] FTP session ended from [IP]

Let me check the related code once again.

@maziggy commented on GitHub (Mar 17, 2026): Every time you are trying to send the file it shows >2026-03-16 22:01:24,215 INFO [backend.app.services.virtual_printer.ftp_server] FTP -> [IP]: 530 Login incorrect >2026-03-16 22:01:24,215 WARNING [backend.app.services.virtual_printer.ftp_server] FTP failed login from [IP] >2026-03-16 22:01:24,216 INFO [backend.app.services.virtual_printer.ftp_server] FTP session ended from [IP] Let me check the related code once again.

BreizhHardware commented

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@maziggy commented on GitHub (Mar 17, 2026):

Still cannot reproduce the issue.

Please do the following:

delete your X1C VP
disable all other VP instances
pull dev branch and rrestart Bambuddy
Enable debug logging
Add X1C VP on review mode and set access code
Try again to send files via slicer

I've added some more debug logs and we should see what's happening.

@maziggy commented on GitHub (Mar 17, 2026): Still cannot reproduce the issue. Please do the following: 1. delete your X1C VP 2. disable all other VP instances 3. pull dev branch and rrestart Bambuddy 4. Enable debug logging 5. Add X1C VP on review mode and set access code 6. Try again to send files via slicer I've added some more debug logs and we should see what's happening.

BreizhHardware commented

bambuddy-support-20260317-115323.zip

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@VREmma commented on GitHub (Mar 17, 2026):

@VREmma commented on GitHub (Mar 17, 2026): [bambuddy-support-20260317-115323.zip](https://github.com/user-attachments/files/26061210/bambuddy-support-20260317-115323.zip)

BreizhHardware commented

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@VREmma commented on GitHub (Mar 17, 2026):

Now... it might be something tied to secondary aliases... I can print to the X1C VP when its on the default IP of the server... and I can print to the same thing when I change it to H2D. But I can't print to a printer that's not on the primary IP at this point. So it might not be an X1C thing that Im seeing...

@VREmma commented on GitHub (Mar 17, 2026): Now... it might be something tied to secondary aliases... I can print to the X1C VP when its on the default IP of the server... and I can print to the same thing when I change it to H2D. But I can't print to a printer that's not on the primary IP at this point. So it might not be an X1C thing that Im seeing...

BreizhHardware commented

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@maziggy commented on GitHub (Mar 17, 2026):

I've been able to reproduce and resolve a similar issue on my end. The root cause was stale or misconfigured iptables NAT rules that redirect port 990 → 9990 (and the passive data port range 50000-50100). When these rules get duplicated or fall out of sync, the FTP connection either gets refused or silently redirected to the wrong place.

Could you try the following?

Check your current iptables NAT rules:
sudo iptables -t nat -L PREROUTING -n -v --line-numbers
Look for any rules involving ports 990 or 50000:50100. If you see duplicates or stale entries, remove them all:
sudo iptables -t nat -D PREROUTING -p tcp --dport 990 -j REDIRECT --to-port 9990
sudo iptables -t nat -D PREROUTING -p tcp --dport 50000:50100 -j REDIRECT
(Repeat each command until it says "No chain/target/match by that name" — that means all copies are removed.)
Re-add them cleanly:
sudo iptables -t nat -I PREROUTING -p tcp --dport 990 -j REDIRECT --to-port 9990
sudo iptables -t nat -I PREROUTING -p tcp --dport 50000:50100 -j REDIRECT
Restart Bambuddy and try sending again.

Also, I've added better diagnostics to the VP FTP/MQTT logs in the latest dev build — each log line now shows which virtual printer it belongs to (e.g. [Virtual - X1C]), which will make it much easier to trace issues like this in the future.

Let me know if that resolves it!

@maziggy commented on GitHub (Mar 17, 2026): I've been able to reproduce and resolve a similar issue on my end. The root cause was stale or misconfigured iptables NAT rules that redirect port 990 → 9990 (and the passive data port range 50000-50100). When these rules get duplicated or fall out of sync, the FTP connection either gets refused or silently redirected to the wrong place. Could you try the following? 1. Check your current iptables NAT rules: sudo iptables -t nat -L PREROUTING -n -v --line-numbers 2. Look for any rules involving ports 990 or 50000:50100. If you see duplicates or stale entries, remove them all: sudo iptables -t nat -D PREROUTING -p tcp --dport 990 -j REDIRECT --to-port 9990 sudo iptables -t nat -D PREROUTING -p tcp --dport 50000:50100 -j REDIRECT 2. (Repeat each command until it says "No chain/target/match by that name" — that means all copies are removed.) 3. Re-add them cleanly: sudo iptables -t nat -I PREROUTING -p tcp --dport 990 -j REDIRECT --to-port 9990 sudo iptables -t nat -I PREROUTING -p tcp --dport 50000:50100 -j REDIRECT 4. Restart Bambuddy and try sending again. Also, I've added better diagnostics to the VP FTP/MQTT logs in the latest dev build — each log line now shows which virtual printer it belongs to (e.g. [Virtual - X1C]), which will make it much easier to trace issues like this in the future. Let me know if that resolves it!

BreizhHardware commented

bambuddy-support-20260317-123220.zip

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@VREmma commented on GitHub (Mar 17, 2026):

Okay, did as you suggested, and even went as far as rebooting (after persisting the rules), and I am still getting the same thing on secondary ips...

@VREmma commented on GitHub (Mar 17, 2026): Okay, did as you suggested, and even went as far as rebooting (after persisting the rules), and I am still getting the same thing on secondary ips... <img width="862" height="257" alt="Image" src="https://github.com/user-attachments/assets/a9fd0eaf-149b-447f-9d3a-5e55ac621716" /> [bambuddy-support-20260317-123220.zip](https://github.com/user-attachments/files/26062302/bambuddy-support-20260317-123220.zip)

BreizhHardware commented

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@maziggy commented on GitHub (Mar 17, 2026):

It always shows

2026-03-17 12:31:41,526 WARNING [backend.app.services.virtual_printer.ftp_server] [Virtual-X1] FTP failed login from [IP] (access code mismatch)
2026-03-17 12:31:50,973 WARNING [backend.app.services.virtual_printer.mqtt_server] [Virtual-X1] MQTT auth failed for user 'bblp' (access code mismatch)

@maziggy commented on GitHub (Mar 17, 2026): It always shows 2026-03-17 12:31:41,526 WARNING [backend.app.services.virtual_printer.ftp_server] [Virtual-X1] FTP failed login from [IP] (access code mismatch) 2026-03-17 12:31:50,973 WARNING [backend.app.services.virtual_printer.mqtt_server] [Virtual-X1] MQTT auth failed for user 'bblp' (access code mismatch)

BreizhHardware commented

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@maziggy commented on GitHub (Mar 17, 2026):

Sorry, but also when choosing an interface alias I cannot reproduce the issue. Hmmm....let me think about it a little bit.

@maziggy commented on GitHub (Mar 17, 2026): Sorry, but also when choosing an interface alias I cannot reproduce the issue. Hmmm....let me think about it a little bit.

BreizhHardware commented

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@maziggy commented on GitHub (Mar 17, 2026):

How many diigits has your access code?

@maziggy commented on GitHub (Mar 17, 2026): How many diigits has your access code?

BreizhHardware commented

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@maziggy commented on GitHub (Mar 17, 2026):

Wait....when looking at your screenshot again: you have no target printer selected?!

@maziggy commented on GitHub (Mar 17, 2026): Wait....when looking at your screenshot again: you have no target printer selected?! <img width="1263" height="741" alt="Image" src="https://github.com/user-attachments/assets/2cc8cdbb-5072-423f-bc9e-79f2b254269c" />

BreizhHardware commented

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@VREmma commented on GitHub (Mar 17, 2026):

I dont have a target printer... because I have multiple of some printers. I end up printing to the VP, and storing it in the archive, so I can have my wife send prints after she clears plates, without having to do slicer stuff herself... I have also hit the logout button in BambuStudio for each Virtual Printer to onboard them again inside the slicer. Its weird, it was working on a previous version (I dont remember the build / tag) until I did upgrades yesterday...

If its just me, i'll live with it.

@VREmma commented on GitHub (Mar 17, 2026): I dont have a target printer... because I have multiple of some printers. I end up printing to the VP, and storing it in the archive, so I can have my wife send prints after she clears plates, without having to do slicer stuff herself... I have also hit the logout button in BambuStudio for each Virtual Printer to onboard them again inside the slicer. Its weird, it was working on a previous version (I dont remember the build / tag) until I did upgrades yesterday... If its just me, i'll live with it.

BreizhHardware commented

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@maziggy commented on GitHub (Mar 17, 2026):

The error is clear

2026-03-17 12:31:41,526 WARNING [backend.app.services.virtual_printer.ftp_server] [Virtual-X1] FTP failed login from [IP] (access code mismatch)
2026-03-17 12:31:50,973 WARNING [backend.app.services.virtual_printer.mqtt_server] [Virtual-X1] MQTT auth failed for user 'bblp' (access code mismatch)

But why is that?

@maziggy commented on GitHub (Mar 17, 2026): The error is clear >2026-03-17 12:31:41,526 WARNING [backend.app.services.virtual_printer.ftp_server] [Virtual-X1] FTP failed login from [IP] (access code mismatch) >2026-03-17 12:31:50,973 WARNING [backend.app.services.virtual_printer.mqtt_server] [Virtual-X1] MQTT auth failed for user 'bblp' (access code mismatch) But why is that?

BreizhHardware commented

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@VREmma commented on GitHub (Mar 17, 2026):

Each printer had a different access code before.... When I just set them both to the same thing (12345678), they both work now....

@VREmma commented on GitHub (Mar 17, 2026): Each printer had a different access code before.... When I just set them both to the same thing (12345678), they both work now....

BreizhHardware commented

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@maziggy commented on GitHub (Mar 17, 2026):

OMG, now that's a clue! I'm also using the same code for all my VP.

That should be easy to fix. Will do it tomorrow morning first. Done with today :)

@maziggy commented on GitHub (Mar 17, 2026): OMG, now that's a clue! I'm also using the same code for all my VP. That should be easy to fix. Will do it tomorrow morning first. Done with today :)

BreizhHardware commented