Marc Auslander wrote: > I have an Realtek Semiconductor Co., Ltd. RTL8101/2/6E PCI Express > Fast/Gigabit Ethernet controller (rev 02) Subsystem: Acer Incorporated [ALI] > RTL810xE PCI Express Fast Ethernet controller > > There is also a Realtek Semiconductor Co., Ltd. Device 8161 (rev 15) > Subsystem: Realtek Semiconductor Co., Ltd. Device 8168 100BaseT not > being used. > > lspci -v says the driver is R8169 for both. > > firmware-realtek is installed and does not appear to provide R8169 but I'm a > novice about these things. > > The cable leading to the debian computer, when connected to a different > computer, runs at almost 1000 Mb according to iperf3. > > When talking to Debian Buster it runs about 100Mb give or take. > > ethtool says its running Speed: 1000Mb/s Duplex: Full > > I just noticed this - in the past it ran at 1000Mb/s rates. It may have > happened when I recently went from squeeze to buster, but I can't be sure of > that.
Please give us names for the computers in question so we know where the problem lies. Is it one computer which changes depending on whether it is booted into buster or bullseye? iperf3 is a pretty good measure of actual data transfer. If it works at 1000Mb/s for most things, but drops to 100Mb/s for a particular one, suspect the particular device, not the general one. -dsr-
