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I have some issues with my router, I mean I have to power cycle in order to raise Ethernet. I have to do this after every system reboot. Sometimes waking from standby needs router power cycled. Sometimes the LAN is orange instead green and when is orange the speed is 100Mb/s in Full Duplex mode. But most of the time is green and 10Mb/s and Half Duplex mode.
I think this is not the Ethernet card issue but router malfunction. I can change speed to 100Mb/s and to FD mode and LAN light goes orange (100FD).
I am guessing the router does not have the 100FD but 100HD only (screenshot attached). How can I check?
On the other hand there is only one node in my 'network' and secondly do I need 100Mb/s since my ISP allows only 6Mb/s?
Any thoughts please. Thanks in advance!
Code:
ethtool enp4s0
Settings for enp4s0:
Supported ports: [ TP MII ]
Supported link modes: 10baseT/Half 10baseT/Full
100baseT/Half 100baseT/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
Advertised pause frame use: Symmetric Receive-only
Advertised auto-negotiation: Yes
Advertised FEC modes: Not reported
Link partner advertised link modes: 10baseT/Half
Link partner advertised pause frame use: No
Link partner advertised auto-negotiation: No
Link partner advertised FEC modes: Not reported
Speed: 10Mb/s
Duplex: Half
Auto-negotiation: on
Port: Twisted Pair
PHYAD: 0
Transceiver: external
MDI-X: Unknown
Supports Wake-on: pumbg
Wake-on: g
Link detected: yes
Do a search for your distro and look at disabling auto-negotiation on enp4s0, I've had this before with some NICs and forcing the NIC in to a specific mode stops it.
I've had a few ethernet ports fail over the years on both PCs and switches.
You can force the ethernet port to 100 and restart the router to see if that works buy otherwise I don't know of anyway to force the LAN port to 100. It is probably time to replaces it.
Distribution: SOLARIS/BSD-like, some Debian-like, some Arch-like, some GENTO-like, some RH-like, some slacky-like
Posts: 385
Original Poster
Rep:
I can change but need to reboot to see if the change is persistent (probably not):
Code:
#ethtool -s enp4s0 autoneg off speed 100 duplex full
# ethtool enp4s0
Settings for enp4s0:
Supported ports: [ TP MII ]
Supported link modes: 10baseT/Half 10baseT/Full
100baseT/Half 100baseT/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
Advertised pause frame use: Symmetric Receive-only
Advertised auto-negotiation: No
Advertised FEC modes: Not reported
Speed: 100Mb/s
Duplex: Full
Auto-negotiation: off
Port: Twisted Pair
PHYAD: 0
Transceiver: external
MDI-X: Unknown
Supports Wake-on: pumbg
Wake-on: g
Link detected: yes
Also I tried:
Code:
nmcli c edit "Ethernet connection 1"
and change the auto-negotiation to no, save it but for some reasons is not saved. The auto-negotiations still on. (save persistent is not recognised command).
ethtool enp4s0
Settings for enp4s0:
Supported ports: [ TP MII ]
Supported link modes: 10baseT/Half 10baseT/Full
100baseT/Half 100baseT/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
Advertised pause frame use: Symmetric Receive-only
Advertised auto-negotiation: Yes
Advertised FEC modes: Not reported
Link partner advertised link modes: 10baseT/Half
Link partner advertised pause frame use: No
Link partner advertised auto-negotiation: No
When an auto-negotiating unit meets older equipment that doesn't advertise its capabilities, you'll end up with [initial link speed for the non-negotiating partner]/half duplex. In this case that would be 10Mbps/half duplex.
I have some pretty old ZyXEL equipment that's still in use, but I can't say I've ever encountered one that doesn't implement 802.3 autonegotiation. Although to be fair, the standard specified it as "optional" for 100Base-TX. How old is that P-600 of yours?
(You can still run into this issue with "dumb" 100Mbps fiber-to-copper media converters, but in such cases the resulting link speed would be 100Mbps, half duplex. Which is less than ideal, as the fiber side will be running full duplex regardless.)
It could be that the router is somewhat slow to initialize its interfaces after a reboot. Does the issue persist if you disconnect and reconnect the cable after a few seconds? And when you say you need to power cycle in order to get a link, do you mean the router or the computer?
Have you tried putting a reasonably recent switch between the PC and the router? If a switch manages to negotiate a proper connection, then perhaps there's an issue with the NIC in the PC, or its driver.
And of course I have to mention this: Have you tried a different cable? A faulty or incorrectly crimped cable will lead to exactly the kind of symptoms you're experiencing.
Your router is clearly capable of 100Mbps link speeds, but does it run in half duplex or full duplex? My money would be on the former, but as it doesn't seem to advertise its capabilities, you'll have to do some detective work.
Put a bit of load on the line by starting a download or playing a YouTube video, and look for signs of duplex mismatch:
If your computer uses half duplex while the router is set to full duplex, running ifconfig on the computer will show an abnormally high (and steadily increasing) number of collisions (under "TX errors").
If the computer is operating in full duplex mode while the router expects half duplex, ifconfig will report a (somewhat slowly) increasing number of frame errors (under "RX errors"). A more sophisticated diagnostic tool might report a number of "runts" and "CRC Errors".
In both cases you'll see sub-par performance, although it might not be all that noticeable if the WAN connection is significantly slower than the LAN link speed, as indeed it is in your case.
If you can figure out what the correct settings are, I guess you could configure your PC to use those settings and call it a day. However, the whole situation does strike me as a bit odd, as I really would have expected the router to support 802.3 autonegotiation. For comparison, I just checked a switchport connected to a ZyXEL G-570S, and sure enough, autonegotiation is working and I get 100Mbps/FD. And that thing is 17 years old.
Distribution: SOLARIS/BSD-like, some Debian-like, some Arch-like, some GENTO-like, some RH-like, some slacky-like
Posts: 385
Original Poster
Rep:
Quote:
Originally Posted by Ser Olmy
No need to shout.
Your router is clearly capable of 100Mbps link speeds, but does it run in half duplex or full duplex? My money would be on the former, but as it doesn't seem to advertise its capabilities, you'll have to do some detective work.
Put a bit of load on the line by starting a download or playing a YouTube video, and look for signs of duplex mismatch:
If your computer uses half duplex while the router is set to full duplex, running ifconfig on the computer will show an abnormally high (and steadily increasing) number of collisions (under "TX errors").
If the computer is operating in full duplex mode while the router expects half duplex, ifconfig will report a (somewhat slowly) increasing number of frame errors (under "RX errors"). A more sophisticated diagnostic tool might report a number of "runts" and "CRC Errors".
In both cases you'll see sub-par performance, although it might not be all that noticeable if the WAN connection is significantly slower than the LAN link speed, as indeed it is in your case.
If you can figure out what the correct settings are, I guess you could configure your PC to use those settings and call it a day. However, the whole situation does strike me as a bit odd, as I really would have expected the router to support 802.3 autonegotiation. For comparison, I just checked a switchport connected to a ZyXEL G-570S, and sure enough, autonegotiation is working and I get 100Mbps/FD. And that thing is 17 years old.
Code:
ethtool enp4s0
Settings for enp4s0:
Supported ports: [ TP MII ]
Supported link modes: 10baseT/Half 10baseT/Full
100baseT/Half 100baseT/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
Advertised pause frame use: Symmetric Receive-only
Advertised auto-negotiation: No
Advertised FEC modes: Not reported
Speed: 100Mb/s
Duplex: Full
Auto-negotiation: off
Port: Twisted Pair
PHYAD: 0
Transceiver: external
MDI-X: Unknown
Supports Wake-on: pumbg
Wake-on: g
Link detected: yes
and the router is 100/HD as per attached screenshot
router is attached also changed itself to 100/FD (I did not power cycle).
The main thing is this time I was able to reboot the computer and connection did not drop! No need to power cycle.
Secondly I can unplug the Ethernet cable and when I plug in connects right away (100/FD). Before I had to power cycle the router and it was 10/HD. So as far I see the issue solved changing to 100/FD. Autoneg is on. Thank you so much!
p.s. I fiddled with some setting and I got stuck with the following"
Code:
nmcli 802-3-ethernet.wake-on-lan-password> describe
=== [wake-on-lan-password] ===
[NM property description]
If specified, the password used with magic-packet-based Wake-on-LAN, represented as an Ethernet MAC address. If NULL, no password will be required.
nmcli 802-3-ethernet.wake-on-lan-password> set
Enter 'wake-on-lan-password' value: xxxxxxxx
Error: failed to set 'wake-on-lan-password' property: 'xxxxxxxx' is not a valid Ethernet MAC
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