ASUS ZenWiFi BT10 - Why did LAN Port Drop from 1G to 100 Mbps?

[MD_Network]

I just installed a new ASUS ZenWiFi BT10, updated to latest firmware, and connected BT10 to 1GB Fiber using 20-ft Cat 8 flat cables.

I was experiencing wired 941 up/down internet speeds on 10G LAN2 and 3 ports.

Then all of a sudden, I am now showing a yellow 100 Mbps notice on both 10G LAN2 and 3 ports.

I have tried the following with no change

1. Swapped cables (including short Cat7)
2. Factory reset
3. Confirmed latest FW

I am stumped how I lost 1GB wired speeds on LAN2 and 3 ports and stuck with 100 Mbps. Anyone have suggestions what else to try?

 

[degrub]

Maybe the issue is the port on the device you are connecting from rather than the ASUS.

 

[MD_Network]

Maybe the issue is the port on the device you are connecting from rather than the ASUS.

Do not think so. Brand new MacBook Pro M4 connected to a new hub with 1GB ethernet port. Been working fine until suddenly stopped the 1GB speeds.

 

[bbunge]

connected to a new hub with 1GB ethernet port

Is it an Ethernet hub or Ethernet switch (there is a difference)? If a switch, managed or unmanaged?

I would suspect a flat CAT 8 cable. I know they are supposed to be tested and rated but.. I would put my money on a good UTP pre made Ethernet cable CAT 5e or maybe up to CAT 7. Flat cables over 9 feet...NO! And if you are connecting to 1 GB ports CAT 5e is all you need.

 

[MD_Network]

It is a T

Is it an Ethernet hub or Ethernet switch (there is a difference)? If a switch, managed or unmanaged?

I would suspect a flat CAT 8 cable. I know they are supposed to be tested and rated but.. I would put my money on a good UTP pre made Ethernet cable CAT 5e or maybe up to CAT 7. Flat cables over 9 feet...NO! And if you are connecting to 1 GB ports CAT 5e is all you need.

It is a Thunderbolt Dock hub with a 2.5GB port, that sends ethernet out via Thunderbolt 4 usb-c to MacBook Pro M4.

Well, I did nothing and I have LAN 3 port active again at 1GB connection speed.

 

[degrub]

a couple things -
1) ethernet chipsets 2.5Gbit and above, particularly 10Gbit versions seem to be sensitive to cable quality.
2) higher versions of cables CAT7 and above, are sensitive to proper shield termination and connector fit.
3) 2.5Gbit ethernet chipsets don't always play nice with chipsets that support 5 and 10 Gbit ethernet leading to intermittent issues or outright incompatability. 10Gbit and 1 Gbit seem to be the least trouble with each other.
4) Apple doing their own thing can also cause networking issues. Or not.

 

[jksmurf]

a couple things -
1) ethernet chipsets 2.5Gbit and above, particularly 10Gbit versions seem to be sensitive to cable quality.
2) higher versions of cables CAT7 and above, are sensitive to proper shield termination and connector fit.
3) 2.5Gbit ethernet chipsets don't always play nice with chipsets that support 5 and 10 Gbit ethernet leading to intermittent issues or outright incompatability. 10Gbit and 1 Gbit seem to be the least trouble with each other.
4) Apple doing their own thing can also cause networking issues. Or not.

Just a general comment, as I’ve noticed the issue with both 1Gbps and 2.5Gbps (WAN, often RT-AX86U) arising a fair bit on these forums (over time), i.e. that there do seem to be a few different contributory factors to this observation of the yellow “100Gbps” symbol appearing unexpectedly. Doing a search on “100Mbps” AND “1Gbps” (2.5Gbps) and variations on that, definitely throws up a few results (even for recent BE models), some of which are related.

So yeah in addition to the potential list above, there is the known (fixed in later FW?) issues of the 2.5Gbps WAN power on the RT-AX86U being flaky and the most common one being the device you’re connected to (which is not actually an issue!).

I believe I’ve also seen on these forums some reference to it simply being misreported in the GUI. Hopefully future FW will fix these kinds of issues, if that is indeed occurring.