I want to upgrade my server nic to a TrendNet TEG-25GECTX.

I'm told that is has the Realtek RTL8125B controller, although I cannot find anything on their website to confirm this.

In the past, some nics had lots of issues with Unraid.

I'm current with 7.1.4

I searched this forum for the Realtek RTL8125B and was surprised not to find anything. I did find several hits for Realtek 8125 and it looks like I will need a plugin. My current Intel controller does not require any plugin. I'm concerned how stable the plugin is, and what about future unraid updates / upgrades.

Why doesn't the base unraid have the Realtek drivers, meaning why should we need a plugin?

Anyone use this nic in their unraid server with success? Any driver issues that I need to be aware of?

Edited September 21, 2025Sep 21 by optiman

there are drive plugins for the relatek. its more a issues with realtek and intel changes for new hardware in the linux kernel.

I'm not aware of any isseus with

the Realtek RTL8125B

in the lattest 7.1.4 with the driver plugin.

just be sure to install the driver plugin:

Q/A

Q: Why doesn’t the base Unraid include Realtek drivers by default, meaning why do we need a plugin?

Unraid is built on a Slackware-based Linux kernel that Limetech compiles with a focus on stability. Only drivers that are considered stable, open-source, and well-maintained upstream get included directly in the kernel builds.

Realtek network adapters are notorious for having multiple revisions with slightly different chipsets, and the official drivers are often out-of-tree (not merged into the Linux kernel). Some of their code is proprietary, or at least not maintained in the mainline kernel. As a result, Linux will include a “basic” in-kernel driver for Realtek NICs, but it may not fully support every revision (like the RTL8125/RTL8125B). That’s why community or 3rd-party plugins exist: they package Realtek’s newer driver and make it work with Unraid’s kernel.

Q: In the past, some NICs had lots of issues with Unraid. Is this still true?

Yes, Realtek NICs have historically been more problematic on Linux than Intel NICs. Issues include link drops, poor throughput, and stability problems. Many of these problems stem from Realtek’s lag in upstream driver support. Intel NICs generally “just work” because their drivers are upstream, well-maintained, and included in the kernel.

For Realtek 2.5GbE (RTL8125/8125B), the situation has improved a lot. With the proper plugin/driver, they are usually stable. But, compared to Intel or Broadcom NICs, there’s still a higher risk that a future kernel upgrade could break support until the plugin catches up.

Q: Has anyone used the TrendNet TEG-25GECTX in Unraid successfully?

The TrendNet card is just a board partner’s implementation of the Realtek RTL8125B controller... similar to how different vendors make GeForce graphics cards using the same NVIDIA GPU. Functionally, it’s a Realtek 8125B NIC.

Users on the Unraid forums have reported success with 8125/8125B controllers once the Realtek plugin is installed. The main caution is that stability depends on the Realtek driver plugin being maintained in sync with Unraid kernel releases.

The latest release of the Linux 6.12 kernel is 6.12.48, which was released on September 19, 2025, and is supported as a Long Term Support (LTS) kernel until at least December 2026...

https://en.wikipedia.org/wiki/Linux_kernel_version_history

The TEG-25GECTX uses the Realtek RTL8125B chipset

Q: Anyone use this nic in their unraid server with success? Any driver issues that I need to be aware of?

I personally haven't used that vendor in a while and don't have this hardware. I'm not aware of any gotchas except some users have reported getting realtek higher than 1GB nic and only seeing 1 GB speed. This has been answered int eh forum as its a eth tool issue with the nic no having the 2.5 or height advertising speeds. Explained here
https://forums.unraid.net/topic/141349-plugin-realtek-r8125-r8126-r8168-and-r815267-drivers/#findComment-1279775

Due to these issues, i've stayed away from both intel and realtek. it's more of what is the current kernel doing and what's available and been added. then what has unraid/limetek done to keep with the current kernel. Usually these driver issues are fixed in the next kernel. However unraid has been following openzfs for kerneal support and major kerneal changes and updates are slowed due to waiting on openzfs to support the next kernel upgrade. https://github.com/openzfs/zfs/releases

(This is an example of why debain stayed on 6.1 LTS kernel... 6.12 kernel are in active development and we are the testers...) Unraid is also not a major corporation and is limited by hardware and access to test everything. there are also unsupported 3rd party built kernel but that very advance Linux and bzroot manipulation that I wouldn't recommend.

So if you use this hardware and a driver plugin Its recommend to stay on the current SATBLE LTS version. AS I've seen users with beta test version. If Limetech bumps the kernel and the plugin isn’t updated immediately, you could lose network access until the plugin catches up. Which has been a problem for a few but not most end users that run the realtek hardware.
Release notes also go over some help full information as well
https://docs.unraid.net/unraid-os/release-notes/7.1.4/

such as what kernel they are running

Linux kernel

• version 6.12.24-Unraid (no change)

Unriad is built on Slackware linux which done't see much support then other mainstream distro like arch or Debian or RFLE...

Edited September 21, 2025Sep 21 by bmartino1
data and info - spelling

Awesome reply with tons of great information here, THANK YOU!

I will go ahead and try it.

Cheers