Issue with OP Entry Delay and Failures in LinuxCNC + EtherCAT System

I'm updating to Debian 13 and I see it's downloading version 6.12.48 now.
I'm really excited—this issue has been bothering me for nearly half a year, and I hope it gets resolved.

# lspci
01:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller (rev 15)
02:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller (rev 15)

Then at least part of the problem is with the Realtek network adapter.
There are two things you can try
1. Install the realtek-dkms drivers and use them instead of the default realtek drivers. Search in the forum for info, many people has done that.
2. Install a PCIe Intel network adapter.
 

Hi, I'm back to provide feedback.
Following your instructions, I have solved this problem. It worked after I updated the r8168-dkms network card driver.
The datagrams UNMATCHED situation no longer occurs. The device can enter the PREOP state normally as soon as it starts, and it can enter the OP state 100% of the time. Previously, some slaves were in INIT+E or PREOP+E state.
Thank you so much!

Happy to hear that!
And to get feedback that the dkms driver really helps.