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megonil

Member

Registered: 2025-03-15

Posts: 5

Ethtool failed to set speed 1000(Realtek)

Hello, this is my first post. Sorry for bad english.

I'm trying to set my ethernet connection speed to 1000 with ethtool, but if i type something like ethtool -s enp4s0 speed 1000 duplex full autoneg on, my connection will simply crash and resulting with  Unknown speed in ethtool enp4s0.  What ethtool enp4s0 gives:

Settings for enp4s0:
	Supported ports: [ TP ]
	Supported link modes:   10baseT/Half 10baseT/Full
	                        100baseT/Half 100baseT/Full
	                        1000baseT/Full
	Supported pause frame use: Symmetric Receive-only
	Supports auto-negotiation: Yes
	Supported FEC modes: Not reported
	Advertised link modes:  10baseT/Half 10baseT/Full
	                        100baseT/Half 100baseT/Full
	                        1000baseT/Full
	Advertised pause frame use: No
	Advertised auto-negotiation: Yes
	Advertised FEC modes: Not reported
	Link partner advertised link modes:  10baseT/Half 10baseT/Full
	                                     100baseT/Half 100baseT/Full
	Link partner advertised pause frame use: No
	Link partner advertised auto-negotiation: Yes
	Link partner advertised FEC modes: Not reported
	Speed: 100Mb/s
	Duplex: Full
	Auto-negotiation: on
	Port: Twisted Pair
	PHYAD: 0
	Transceiver: internal
	MDI-X: on
	Supports Wake-on: pumbg
	Wake-on: d
        Current message level: 0x00000033 (51)
                               drv probe ifdown ifup
	Link detected: yes

What happens after i change speed:

Settings for enp4s0:
	Supported ports: [ TP ]
	Supported link modes:   10baseT/Half 10baseT/Full
	                        100baseT/Half 100baseT/Full
	                        1000baseT/Full
	Supported pause frame use: Symmetric Receive-only
	Supports auto-negotiation: Yes
	Supported FEC modes: Not reported
	Advertised link modes:  1000baseT/Full
	Advertised pause frame use: No
	Advertised auto-negotiation: Yes
	Advertised FEC modes: Not reported
	Speed: Unknown!
	Duplex: Unknown! (255)
	Auto-negotiation: on
	Port: Twisted Pair
	PHYAD: 0
	Transceiver: internal
	MDI-X: Unknown
	Supports Wake-on: pumbg
	Wake-on: d
        Current message level: 0x00000033 (51)
                               drv probe ifdown ifup
	Link detected: no

And what lspci -k gives

04:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8111/8168/8211/8411 PCI Express Gigabit Ethernet Controller (rev 15)
	Subsystem: Micro-Star International Co., Ltd. [MSI] Device 7d24
	Kernel driver in use: r8168
	Kernel modules: r8169, r8168

edit: my router is gigabit capable, i checked it. And when my os was windows i had 500-600 due to the limitations of my internet provider
I may not answer quick

Last edited by megonil (2025-03-16 19:05:24)

-thc

Member

Registered: 2017-03-15

Posts: 859

Re: Ethtool failed to set speed 1000(Realtek)

Do you realize that the other side of your ethernet cable

Link partner advertised link modes:  10baseT/Half 10baseT/Full
                                         100baseT/Half 100baseT/Full

seems to be limited to 100 MBit?

seth

Member

Registered: 2012-09-03

Posts: 63,078

Re: Ethtool failed to set speed 1000(Realtek)

*Ifff* you assume that the link partner is gigabit-capable, check the cables.

Also please use [code][/code] tags. Edit your post in this regard.

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megonil

Member

Registered: 2025-03-15

Posts: 5

Re: Ethtool failed to set speed 1000(Realtek)

Do you realize that the other side of your ethernet cable
seems to be limited to 100 MBit?

In settings of port(LAN3 which i connected to) in advertised modes  i have 1000 speed and full duplex. Also, read the edit.
Idk why ethtool cannot see 1000 advertised speed.

seth

Member

Registered: 2012-09-03

Posts: 63,078

Re: Ethtool failed to set speed 1000(Realtek)

*Ifff* you assume that the link partner is gigabit-capable, check the cables.

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mackin_cheese

Member

Registered: 2025-01-07

Posts: 448

Re: Ethtool failed to set speed 1000(Realtek)

Have you perhaps confirmed your cables are capable?

dimich

Member

From: Kharkiv, Ukraine

Registered: 2009-11-03

Posts: 349

Re: Ethtool failed to set speed 1000(Realtek)

This issue ofter happens when one of cable connectors is poorly clamped.
Check if your cable has 4 twisted pairs (8 wires).
Test your cable with network cable tester if you have one.
Check connection with another definitely working cable.
Re-crimp connectors on your cable.

megonil

Member

Registered: 2025-03-15

Posts: 5

Re: Ethtool failed to set speed 1000(Realtek)

Have you perhaps confirmed your cables are capable?

My cable says Cat.7 Flat Cable, so if it's true then it is capable

megonil

Member

Registered: 2025-03-15

Posts: 5

Re: Ethtool failed to set speed 1000(Realtek)

This issue ofter happens when one of cable connectors is poorly clamped.
Check if your cable has 4 twisted pairs (8 wires).
Test your cable with network cable tester if you have one.
Check connection with another definitely working cable.
Re-crimp connectors on your cable.

My cable definitely has 4 twisted pairs.
I double-checked that the cable's plugged in fine. I will test another cable soon because i don't have another now

megonil

Member

Registered: 2025-03-15

Posts: 5

Re: Ethtool failed to set speed 1000(Realtek)

This issue ofter happens when one of cable connectors is poorly clamped.
Check if your cable has 4 twisted pairs (8 wires).
Test your cable with network cable tester if you have one.
Check connection with another definitely working cable.
Re-crimp connectors on your cable.

I connected my laptop with Windows to my cable, and on it the speed was also 100, then I connected the cable to my computer and also got 100, but when I reconnected the cable to another port in the router on the laptop I got speed 500-600 and on the computer still 100.

seth

Member

Registered: 2012-09-03

Posts: 63,078

Re: Ethtool failed to set speed 1000(Realtek)

Please don't paraphrase, https://bbs.archlinux.org/viewtopic.php?id=57855 - actually post updated/comparing ethtool outputs after changing the configuration.
Did you test a different cable as well?
(cat7 is certainly not undergraded, but still may be broken - there was a post a long time ago where a similar issue was down to sombody's cat having had fun with the cable…)

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