[SOLVED] 2 PC's directly connected via Crossover cable


Apr 3, 2015
I upgraded my system a few days ago and made the mistake of miscounting the number of PCI slots on my new board. after considering my options i choose to take out my 10g PCI network card since the server I'm connecting to has 4 1g ethernet ports on board. When I was using the 10G PCI card i was able to hit file transfer speeds of 600MB/s (using iSCSI and RAID5 in write-through) now however even tho the two system sit right next to each other connected via single crossover cable (cat6) I can't get a transfer speed any higher than 100MB/s I have confirmed on both systems that the NIC's are configured for 1G speed. are there any tweaks I can make to the advanced area of their properties that may improve that? it was my assumption that directly connecting the two systems and cutting a switch out of the picture would improve the speed but with or with-out a switch the speed remains unchanged, caps off at 102MB/s
You should not be using a cross over cable any more even 100 mbit ports have auto mdix. Some times modern ports get confused by cross over cables. You should always use straight cables.

I will assume you mean MBYTE but that is still confusing. How did you get 600MB when one end was a gigabit port.

The most you will pretty much ever get on gigabit ethenet is about 120MB anyway because of the overhead of the ethernet protocol. It maybe related to how you are doing the copy. You need to test with 1 single large file. This gets complex because sometimes this is caused by some issue with the disk subsystem on either end.

I would try a old line mode program called IPERF. This is a network testing tool that is not affected by the disk or even cpu/memory. Even on fairly crappy machines it gets in the 900+mbit in both directions when there are no network issues.