I’m trying to access the serial port directly in my VMware virtual machine using only VMware’s built-in features, but I can’t figure out the right steps. I need to connect a device to the VM through the serial port for testing, but I’m stuck on how to do this natively—without any third party tools. Any guidance or step-by-step advice would really help.
Serial to Ethernet: Don’t Overthink It
So, native ways are a straight-up headache. Too many hoops. I just fire up Serial to Ethernet Connector when I need to mess with COM ports inside my VM—it’s quick and doesn’t fry my brain. You basically get solid performance after clicking like, twice. Nothing fancy, no command line magic, no cursing at drivers at 2 a.m. Just does what you want, when you want. Sometimes the easy path really is the best.
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Accessing a physical serial port from a VMware virtual machine should be easy, but it kinda feels like VMware wants you to go back to the stone age of computing sometimes. Not knocking you, @mikeappsreviewer, but I actually prefer sticking with the built-in stuff when possible—even if it’s not always a walk in the park.
Here’s how you do it natively (assuming you’re using VMware Workstation or VMware ESXi):
- Shut down your VM. Serial config can’t be changed with the VM running, which is zzz but whatevs.
- Edit VM Settings. Open up the properties/settings for the VM.
- Add a Device: Click “Add” > “Serial Port.” (If it’s already there, select it instead.)
- Choose Port Type: Now, this is the gotcha. You gotta pick from:
- Use physical serial port on the host (e.g., COM1)
- Output to file (dumb unless you want logs)
- Named pipe (fancy, for VMs talking to other VMs or special use cases)
- Select Host Device: If using the actual COM1/COM2 on your computer, pick it explicitly from the dropdown.
CAVEATS, aka Why This Sucks Sometimes:
- A lot of laptops, and pretty much any modern desktop, straight do not have hardware COM ports any more, so you’re stuck using USB-to-Serial adapters. VMware’s not always friendly with those unless you also pass the USB device through instead.
- Don’t even think about hot-plugging USB serial adapters unless you want kernel panics (jk. mostly.)
- ESXi makes you jump through even more hoops if you want to expose serial ports because you either need special PCI passthrough, or to mess with command lines on the host.
If you’re dealing with USB-to-serial adapters, sometimes passing the whole USB device is way less hassle. Still, if all you want to do is map your host’s “real” serial port to the VM, this native approach does work—assuming your hardware isn’t trolling you.
Just my two cents: I get that third-party stuff like Serial to Ethernet Connector does make this a lot easier and lets you route real or virtual serial ports across the network (and platform-agnostic, which is neat). It’s a pay-to-play thing but gets rid of all the “wait, which port am I even connecting” drama that comes with VMware’s aging serial port handling.
BTW, if anyone’s looking to dig deeper into how to set up and manage serial devices in a virtual environment, there are some decent guides out there that cut through the jargon.
TL;DR—VMware native serial port setup is technically possible. Just plan for some trial-and-error if you’re not on old-school hardware. And, yeah, sometimes, not overthinking it (and using a third-party tool) is the real pro move… but I’m stubborn.
If your host even has a physical port (less and less common), you’re stuck powering down VMs, digging through device mapping, fumbling with permissions, and then praying Windows guest OS picks it up without a hissy fit. Tried the native method; it’s finicky and one-to-one—if you want more than one VM or user, the limitations trip you up fast.
Plug-and-play things like Serial to Ethernet Connector just feel… modern. On the plus side: ridiculously easy, supports USB-to-serial dongles, works over the network (huge for laptops without ports), and actually shares ports across VMs/devs. Downsides? It’s paid (not free like VMware settings) and adds a network step (but, honestly, who cares with gigabit speeds?). Other folks here pitched good native setups, but I’m all about practical. Save the hassle—unless you’re doing retro computing cosplay, just virtualize that port.