Ethernet cable sometimes works?

[backward]

I'm connecting my late 2006 Macbook Pro and 2011 Mini directly with a cat6 ethernet cable but it doesn't work. I found this weird workaround though:

- plug in a cat5 cable first: ethernet connects
- unplug cat5 and use the cat6 cable: ethernet connects

I prefer the cat6 cable because it is shorter. I just don't get why I need to "prime" it with the cat5 first. Any ideas why this is happening or how to get the cat6 working on its own?

The cat6 seems to be running at full speed. ifconfig says:

en0: flags=8863<UP,BROADCAST,SMART,RUNNING,SIMPLEX,MULTICAST> mtu 1500
options=2b<RXCSUM,TXCSUM,VLAN_HWTAGGING,TSO4>
ether 3c:07:54:0b:b1:44
inet6 fe80::3e07:54ff:fe0b:b144%en0 prefixlen 64 scopeid 0x6
inet 169.254.1.141 netmask 0xffff0000 broadcast 169.254.255.255
media: autoselect (1000baseT <full-duplex,flow-control>)
status: active

 

[hamshi]

I'm connecting my late 2006 Macbook Pro and 2011 Mini directly with a cat6 ethernet cable but it doesn't work. I found this weird workaround though:

- plug in a cat5 cable first: ethernet connects
- unplug cat5 and use the cat6 cable: ethernet connects

I prefer the cat6 cable because it is shorter. I just don't get why I need to "prime" it with the cat5 first. Any ideas why this is happening or how to get the cat6 working on its own?

The cat6 seems to be running at full speed. ifconfig says:

en0: flags=8863<UP,BROADCAST,SMART,RUNNING,SIMPLEX,MULTICAST> mtu 1500
options=2b<RXCSUM,TXCSUM,VLAN_HWTAGGING,TSO4>
ether 3c:07:54:0b:b1:44
inet6 fe80::3e07:54ff:fe0b:b144%en0 prefixlen 64 scopeid 0x6
inet 169.254.1.141 netmask 0xffff0000 broadcast 169.254.255.255
media: autoselect (1000baseT <full-duplex,flow-control>)
status: active

correct me if im wrong but wouldnt you need a crossover/patch cable to connect them???

 

[backward]

For the most part, the network devices will auto detect and work with either a straight-through or crossover cable.

http://support.apple.com/kb/HT2274

 

[Mr.C]

correct me if im wrong but wouldnt you need a crossover/patch cable to connect them???

It's not necessary with today's computers. They pretty much all have an auto detect feature especially Macs.

 

[hamshi]

It's not necessary with today's computers. They pretty much all have an auto detect feature especially Macs.

i stand corrected

 

[Darien Red Sox]

bad cable, once I spent hours trying to plug a G4 quick silver into the jack in the wall with no luck, finally used internet sharing on my MBP and ran the cable between the two of them. Double checked the wall jack and everything was punched down correctly, took a closer look at the cable and saw that when I had made it two wires were in the wrong location.

 

[backward]

Yeah, it's unfortunate but the cable was faulty from the beginning so I'll probably will have to get a replacement. Thanks guys.