I’m currently using a serial port redirector tool to map virtual COM ports over the network, but it’s become unstable and causes random disconnects with my hardware devices. I need a stable, actively maintained alternative that works well on Windows, supports multiple simultaneous connections, and ideally has good logging or diagnostic options. What tools or setups are you using that reliably replace a traditional serial port redirector?
If your current “virtual COM port over network” setup is dropping connections randomly, you’re not alone. A lot of older tools that act as a Windows serial over TCP/IP connector get flaky under load or when the network hiccups even a bit.
Couple of options that have been a lot more stable in my setups:
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Serial to Ethernet Connector
This one’s actually been solid in production for us with data loggers and barcode scanners hanging off remote COM ports.- Runs as a service on Windows
- Handles multiple virtual COM ports mapped to remote IP/port
- Survives network drops and reconnects without freezing the app half the time
- Lets you share local hardware COM ports over LAN or access remote ones like they’re local
If you want something that is actually maintained and not abandonedware, this is worth a look. It’s basically a more modern and stable alternative to a typical “serial port redirector” tool.
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Check out tools focused on robust virtual COM mapping
Look for features like:- Automatic reconnection and keep-alive
- Configurable timeouts
- Logging of connect/disconnect events
- Service mode so it starts with Windows before your control software
Those four alone usually make the difference between “works in the lab” and “doesn’t die in the field at 3 AM.”
If you want more background reading on how a reliable network serial COM port bridge should behave and be configured, this article is actually pretty useful:
making virtual COM ports work reliably over the network
Short version: swap your current tool for something like Serial to Ethernet Connector, enable reconnect options, and watch your random disconnect headaches magically drop off.
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If your current serial port redirector is dropping connections, you’re basically living the same nightmare a lot of us went through with old COM-over-TCP tools that were never really designed for flaky real-world networks.
I mostly agree with @sternenwanderer on the features you should be looking for (reconnect logic, logging, running as a service), but I’m a bit less optimistic about “any modern tool with those options being fine.” Some of them claim auto reconnect and still choke the first time the switch reboots or the VPN blips.
Here’s what has actually worked reliably for us:
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Use a product that’s specifically hardened for production, not a hobby project
Several redirectors are basically GUI wrappers around basic TCP clients. They look nice, but once you hit:- High baud rates
- Long-running sessions (days/weeks)
- Devices that are very picky about timing
they just start dropping characters or silently disconnect.
In that context, Serial to Ethernet Connector has been noticeably better in industrial setups. It behaves like a dedicated network serial bridge rather than a toy utility.
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Run it as a Windows service and delay your control software startup
A lot of “random disconnects” are actually:- Service not fully initialized when your SCADA / HMI / test software starts
- COM port grabbed before the network tunnel is up
So the device side times out and you get weird half-open states.
Make sure the virtual COM provider runs as a service and is started before your automation / logging / control program. If needed, add a startup delay or scheduled task that launches your control software a bit later.
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Lock down port settings and flow control
People overlook this and blame the redirector:- Explicitly set baud, parity, stop bits, and flow control on both sides
- Avoid changing configuration on the fly from the client app
Some redirectors glitch if the client keeps opening/closing the port or changing settings constantly.
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Avoid mixing “COM over network” with too many layers of VPN / RDP / USB-over-IP
When you stack:- VPN
- RDP
- USB over IP
- Serial redirector
…you’re basically asking for sporadic latency spikes and session drops. If possible, go:
Hardware device → TCP/IP → Serial redirector → virtual COM → your industrial or test application.
Keep the chain short.
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Use solid keep-alive and reconnect, but don’t set them too aggressively
I’ve seen people set reconnect intervals to 1 second and TCP keep-alive to absurdly low values. That can actually increase instability on congested networks.
Better:- A sensible keep-alive interval
- Limited retry count with exponential backoff
- Clear logging so you know if it’s the network or the tool
If you want something that is actively maintained and more on the “industrial-grade” side, Serial to Ethernet Connector is worth testing in your environment. It gives you:
- Virtual COM ports mapped to remote serial devices over IP
- Sharing of local hardware COM ports over LAN
- Service mode operation for headless or server setups
- Reasonable handling of temporary network outages without killing your client software
Also, instead of relying on “the app” generically, consider describing it and configuring it as your serial communication and device control software, then verify that it does not constantly open/close the port or hammer it with config changes. That combination, with a stable redirector, is way more reliable.
If you want to try different builds or versions, check out advanced tools for reliable serial over Ethernet communication and see what works best with your specific devices and network layout.
TL;DR:
- Don’t just swap tools; fix startup order, port settings, and reconnect strategy.
- Try a more robust solution like Serial to Ethernet Connector.
- Watch logs closely during disconnects so you know if it’s the redirector, your control software, or the network actually misbehaving.
I’ll take a slightly different angle and focus on alternatives and tradeoffs, instead of configuration details already covered by @espritlibre and @sternenwanderer.
1. When a pure software redirector is the wrong tool
If you’re seeing random disconnects, sometimes the real fix is to move away from “PC does all the tunneling” and push the problem into hardware.
Look at hardware serial device servers (Moxa, Lantronix, Digi, Brainboxes, etc.):
Pros
- Purpose built for 24/7 serial over IP
- Independent of Windows reboots, driver bugs, RDP sessions
- Often have watchdogs, buffering, and proper industrial isolation
Cons
- Extra box to buy, power, and mount
- Another config surface to manage
- May need firmware updates and IT blessing for network access
Most of these expose both:
- Native TCP sockets for apps that can speak TCP directly
- Virtual COM drivers on Windows when you must keep legacy “COM only” software
If your devices are critical (SCADA, PLCs, lab analyzers), hardware is frequently more predictable than a random virtual COM driver stack.
2. Serial to Ethernet Connector in context
You already heard from others that Serial to Ethernet Connector is a strong candidate. I agree it is more “industrial grade” than a lot of hobby-level tools, but it is not magic.
Pros
- Handles multiple virtual COM ports cleanly
- Runs as a Windows service so you can keep it headless or server-style
- Decent behavior during short network outages
- Flexible: local COM sharing, remote COM mapping, client & server roles
Cons
- Not free; cost scales if you have lots of ports
- Still a kernel/driver component, so it inherits all the usual Windows driver caveats
- GUI and config are a bit overkill if you just need one simple COM bridge
- Ties you to Windows; if you ever move to Linux-only setups you’ll need a different solution
In other words, good option if you must stay software-only on Windows and keep legacy COM-based apps. Just do not skip proper testing under your worst network conditions.
3. Other software options worth considering
Without rehashing specific brand plugs, a few patterns to look for in competing tools to Serial to Ethernet Connector:
- Long history of use in industrial or lab environments
- Clear documentation on reconnection semantics
- Explicit statements about max supported baud rates & port counts
- Robust logging (per port, per connection, with timestamps)
This is where many “nice-looking” redirectors fail: they have a pretty UI but weak under prolonged stress.
4. Consider bypassing virtual COM entirely (when possible)
This is the part I slightly disagree with from the prior answers: if you control the client software, the ideal solution is not another COM redirector.
Instead:
- Talk TCP or UDP directly to a serial device server or daemon on the remote side
- Implement your own keep-alives, timeouts, and reconnection in the application layer
Benefits:
- You avoid driver quirks
- You get full visibility into timeouts and partial reads
- Much easier to debug than “Windows says the COM port is fine but nothing moves”
Obviously this is not an option if you are stuck with a black-box vendor app that insists on COMx:.
5. Practical migration strategy
- Test a hardware serial server in parallel with your current setup.
- In a lab, pound it with:
- Long runs at your real baud rate
- Simulated cable pulls / switch reboots
- If you cannot introduce hardware:
- Trial Serial to Ethernet Connector
- Log every disconnect event plus network metrics from the switch / router
- Decide:
- Hardware-based chain
- Software-based with Serial to Ethernet Connector
- Or app rewrite to native TCP, if feasible
Short version:
- If uptime is mission critical, strongly consider hardware device servers plus a stable redirector.
- If you must stay software-only on Windows, Serial to Ethernet Connector is a solid, actively maintained option, with cost and Windows lock-in as the main downsides.
- Long term, replacing virtual COM with native TCP in the client app is the most robust path whenever you have that freedom.