How do I configure serial ports in VMware?

Networking
1

I’m having issues setting up serial ports in VMware for a virtual machine. I’ve tried following the official documentation, but I still can’t get it to work. I need to use the serial port for a specific application. What steps should I follow, or what might I be missing?

2

Alright, setting up serial ports in VMware can be a real pain sometimes. Let’s get straight to it:

  1. VM Settings:

    • First, shut down the virtual machine (VM) where you want to add the serial port.
    • Go to the VM settings and click on ‘Add Device.’
    • Select ‘Serial Port’ and add a new serial port.

  2. Connection Options:

    • Choose ‘Use physical serial port’ if you have a physical serial port on the host machine. Select the appropriate COM port.
    • If you want to use a file to capture the serial port output, select ‘Use named pipe’ or ‘Use output file’ and specify the file path.

  3. Named Pipes:

    • Using named pipes can be tricky. Make sure Pipe Settings (Server or Client) are set correctly.
    • For instance, if you’re using named pipes, format might be \\.\pipe\pipename. Make sure both the client and server machines agree on this.

  4. Serial to Ethernet Connector:

    • Another workaround is using the Serial to Ethernet Connector. This tool helps redirect serial ports over network, making it seamless if your application needs remote serial port access.
    • Setup is typically straightforward: install the software, configure the serial over network, and you’re good to go.

  5. Windows Configuration:

    • After setting up the serial port in VMware, ensure the guest OS recognizes it. You may need to install appropriate drivers.

  6. Testing:

    • Use applications like PuTTY or HyperTerminal to test if data is passing through the serial connection.

Common Reasons for Issues:

  • Incorrect COM port selection.
  • Mismatched named pipe settings.
  • Missing or outdated drivers in the guest OS.

For more detailed steps, you can check out this video tutorial on VMware serial port passthrough.

Hope this helps! If anyone has additional tips or solutions that worked for them, feel free to chime in.

How do I configure serial ports in VMware?
How do I configure serial ports in VMware?1536×965 194 KB

3

Alright, looks like @chasseurdetoiles covered most bases, but let me throw in a few more things that might be missing.

Before diving back into the VMware settings, ensure the host machine’s BIOS has legacy support for serial ports enabled. Some modern BIOS setups disable legacy peripherals by default, and without that, you’re gonna get nowhere.

Secondly, checking VMware compatibility is crucial. Make sure you’re using a version of VMware that actually supports serial passthrough. Older versions might not have the robust support you need.

On to guest OS configurations: Ensure that the COM port recognized by the host isn’t being hogged by other applications. Sometimes background processes on the host can mess up the configuration.

Another tool that often goes unnoticed is the VMware Tools. Ensure it’s up-to-date within your virtual machine. This tiny utility can solve a plethora of issues, including hardware passthrough problems.

If you’re still pulling your hair out after these steps, try the Serial to Ethernet Connector one more time. Not only can it help with serial over network but also often provides a more stable connection compared to bare-metal passthrough.

Lastly, let’s talk about VM resource allocation. Ensure your VM has enough resources allocated; sometimes a resource-strapped VM struggles with peripheral passthrough.

Testing with apps like PuTTY to verify the connection is spot on. However, if PuTTY shows nothing, consider disabling the firewall or antivirus on your host temporarily as they can sometimes hinder communication between the guest and the host.

Hope these extra steps help someone out there! And don’t hesitate to jump back to this thread with more questions or success stories.

4

Considering what @suenodelbosque and @chasseurdetoiles mentioned, let’s address a few more quirks here. Shutting down the VM and using the VMware interface is relatively standard advice. Yet, there are some nitty-gritty details often overlooked.

BIOS & Hardware Checks

First off, ensure the physical serial port works correctly on the host machine before trying to pass it through to your VM. For this, a quick test with a loopback plug can confirm if the serial port hardware is operational.

VMware Settings Tweak

After adding the serial port in VMware settings:

  1. Edit the VM Configuration File (.vmx): Sometimes manual edits to the .vmx file yield better results than the GUI.
    • Look for entries like serial0.present, serial0.fileName, etc., and modify them if necessary.
    • Add or adjust lines such as serial0.virtualDev = 'tty0' if it’s missing.

Alternatives & Tools

While the Serial to Ethernet Connector is an effective tool, consider its pros and cons:

  • Pros: Easy setup, robust, flexible across networks.
  • Cons: Licensing costs, potential network dependency issues.

Competitors:

  • HW VSP3 and ELTIMA are similar tools but may differ in pricing and functionality.

Guest OS Nuances

In Windows guest OS, delve into Device Manager to make sure the serial port isn’t disabled or flagged with errors. Sometimes re-fetching the port within Windows settings resolves detection issues.

Linux Guests: Ensure proper user permissions to access the serial device using chmod or adding the user to the appropriate group.

Diagnostic Steps

  • Telnet Test: For named pipes, try using telnet to connect manually and see if the pipe is open.
  • TTY Communication: Use screen or minicom on Linux systems to test the serial connection.

On Updating IPTables or Firewalls:

On the host machine, especially if you use named pipes over the network, configure iptables/firewall to allow communication on the necessary ports. This avoids blocks that could sever the serial connection.

Advanced Troubleshooting

Utilize VMware Workstation Pro’s log files (vmware.log) to troubleshoot connection issues. Look for any entries related to the serial port and potential conflicts/denials.

Community Insight

  • Does anyone use the Serial to Ethernet Connector tools differently? Share setups that minimize latency or maximize reliability.
  • Tips on refining VMware’s network adapter settings for better serial port stability?

Integrate these checks, and give the Serial to Ethernet Connector another look. It resolves many quirks folks face with legacy serial port pass-through.