How can I set eth0 speed to be persistent?

[Blaze9]

Hi All,

 

I have two NICs on my server, eth0 and eth1. eth1 is disconnected. eth0 has a cat6 cable connected to a gigabit port on a switch. Whenever I restart my server, eth0 always defaults to 10Mb/s as reported by ethtool. I have to manually set eth0 to be 1000Mb/s and full duplex 

ethtool -s eth0 speed 1000 duplex full

and after a few seconds it then shows the correct speed. It is actually slow, and not just a bug with the eth0 reporting.

 

Any ideas?

[JonathanM]

Typically that is caused by physical connection issues. Check the ports for bent pins, try different cables, etc.

[Frank1940]

Be sure to reboot the switch. (Basically, the switch is a computer and rebooting can clear problems.)  Also, switch the cat6 cable to another port on the switch.  You could do both at the  same time and see if the problem has 'fixed'.  I have had a few switches go bad over the years.   

[NNate]

I had a similar problem a few weeks ago. Turns out my switch was going bad.

[Etti]

Hi, 

i have the same issue, every time I restart the Server it changes to 10MB/s. If I pull the ethernet cable out and back in it works just fine at 1000mb/s. Im tying a solution where I just put the same command you used in a Plugin named User Scripts. It runs the script automatically on the first array start. It's not a fancy solution but maybe it can save you some nerves if it works for you. If you have another solution I would love to hear what you have done to fix it.

 

[Frank1940]

This is a hardware issue.  The speed is set by a negotiation between the switch and the Network Interface Chip/Board.  Failure to get the proper speed is (almost always) found to be a bad switch port, a bad cable or a bad NIC/Board.  You can also try rebooting the switch by power cycling it.  That sometimes resolves these types of problems.