Can't get IP using Apple USB Ethernet

Rob.G

macrumors 6502
Original poster
Jan 17, 2010
471
57
Arizona
This place I'm working for right now requires a cabled network connection. So I had to go spend $30 on Apple's USB Ethernet adapter for my 11" Air. But it's not working.

I've done a lot of Googling and reading. It shows a connection, but the IP is one of the self-assigned ones.

I've tried both USB ports, I've removed and re-added it. I've created a new Location for it. I've ifconfig up/down'd it repeatedly. I've shut off wifi. Nothing is working.

First thing this morning when I got here and plugged in the cable, I did get a "login to the network" box (domain authentication) but I don't get that anymore. So I'm still not sure if the problem is on my Mac or their network. Their IT dept is fairly clueless and slow to respond, so I'm running out of ideas.

Anything else I can try to see if it's something on my end?

Thanks.

Rob
 

PBG4 Dude

macrumors 68030
Jul 6, 2007
2,714
1,872
Have you tried a known good computer on that ethernet connection? Just to rule out the connection itself I guess.
 

johnhurley

macrumors 6502a
Aug 29, 2011
777
52
This place I'm working for right now requires a cabled network connection. So I had to go spend $30 on Apple's USB Ethernet adapter for my 11" Air. But it's not working.

I've done a lot of Googling and reading. It shows a connection, but the IP is one of the self-assigned ones.

I've tried both USB ports, I've removed and re-added it. I've created a new Location for it. I've ifconfig up/down'd it repeatedly. I've shut off wifi. Nothing is working.

First thing this morning when I got here and plugged in the cable, I did get a "login to the network" box (domain authentication) but I don't get that anymore. So I'm still not sure if the problem is on my Mac or their network. Their IT dept is fairly clueless and slow to respond, so I'm running out of ideas.

Anything else I can try to see if it's something on my end?

Thanks.

Rob
If you have a self assigned IP address it sounds like you did not get a dynamic IP from DHCP server.

Lots of places have rules in place and only give out DHCP addresses to machines that meet their own rules ( typically were authenticated somehow ). Lots of places have things that look like you can plug in an ethernet cable but are not turned on at the switch level until an admin configures it.

Try your ethernet adapter at home when you have wifi turned off to make sure that it is working first.

If that works at some other place then you need to work thru steps at the place you are trying to connect it at. See if you can buy lunch for one of the network or system admins.
 

Stewart21

macrumors regular
Dec 9, 2011
187
0
South Yorkshire
The suggestions about checking whether the port you're plugging in to is working is sensible and should be tried but for me the main issue is that you need either an IP Address assigned by DHCP or a fixed IP Address assigned by the network sysadm. Are there any other Macs in the office connected to the network (actually a Windows machine will do) that you can check under System Preferences, Network for a Mac ( somewhere in Control Panel, Networks for Windows I think)?

Look to see if the machine is assigned an IP Address automatically using DHCP , DHCP with a fixed address or Manually. Copy the settings to your machine unless the company are using fixed IP Addresses, someone will be mightily p'd off if you nick their IP Address. If it's manually assigned or fixed you'll need an IP Address issued by the sysadm, personally I find it hard to believe anyone would be mad enough to cause all the extra work this entails but you never know.

Stewart
 

johnhurley

macrumors 6502a
Aug 29, 2011
777
52
If it's manually assigned or fixed you'll need an IP Address issued by the sysadm, personally I find it hard to believe anyone would be mad enough to cause all the extra work this entails but you never know.
Lots of places around here still just using static ip addresses ... security related often.
 

Stewart21

macrumors regular
Dec 9, 2011
187
0
South Yorkshire
Lots of places around here still just using static ip addresses ... security related often.
Mmm, I suppose if you're a small company... I come from an environment with 50,000+ PC's and 1000+ servers, great if you want to maintain employment by doing it all manually.

There are better ways of applying strong security than fixed IP Addresses.

Stewart
 

kjlake

macrumors member
Jul 15, 2010
60
0
It could also be port security which will disable the port at the switch which will exhibit similar behavior. We use that in my organization to mitigate the risk of unapproved devices accessing corporate resources. As others have said, I would try using the USB adapter with a wired connection at home to see if the adapter is functioning. If that works, then the issue is with the corporate network.

Regards

Kevin
 

Rob.G

macrumors 6502
Original poster
Jan 17, 2010
471
57
Arizona
Thanks for all the tips, everybody. We solved the problem by them getting it on to the wireless network. This has been so frustrating... I was told by two different people there that you HAD to have a cable connection, and then one of them a few days later says you can do it on wireless. Sigh.

Anyway... thanks again for the tips!

Rob