Slow ethernet, very fast wifi, how come?! - using Time Capsule

[ayu61200]

Hello,

I'm facing a very misterious issue with my internet connection, using a Time Capsule; If I use a network cable to connect to the Time Capsule, the connection to the internet is very slow (Maxes at 2mbit, never more). If use a wifi connection to connect to the same Time Capsule, internet is flawlessly fast, reaching well over 80Mbit. How is this possible?

I checked and the ip is always the same, the downloads are the same, at the same time. Even trying with 2 computers (a Macbook and an iMac) (one over wifi, one on ethernet cable) the one using wifi can download stuff way faster. If I switch connections the one using wifi is always faster.

I use DHCP for both ethernet and wifi on the same local network, all the machines can see each other, it's just the internet connection that becomes so slow when using ethernet. The local network as as fast as a gigabit connection allows...

The Time Capsule has the latest firmware installed, and has no problems at all besides this internet issue.

Anyone could hint on a reason for this weird behaviour?

 

[jjk454ss]

Check out this thread, it talks about problems with older network cables. Are you using CAT6?

https://forums.macrumors.com/threads/458480/

 

[ayu61200]

Yes, I'm using CAT6... I'll read right now - thanks a lot for the link

 

[ayu61200]

I found the reason of this weird behaviour, I'll post it here for anyone with the same problem to find out how to fix it:

The TC assigned a different DNS configuration to wifi connections than ethernet connections; Ethernet had 'real' ISP DNSs (the ones the TC acquires when obtains the DHCP session). Wifi had the TC's IP as DNS server.

I changed Ethernet DNSs to TC's IP and now internet is amazingly fast.

 

[jjk454ss]

I found the reason of this weird behaviour, I'll post it here for anyone with the same problem to find out how to fix it:

The TC assigned a different DNS configuration to wifi connections than ethernet connections; Ethernet had 'real' ISP DNSs (the ones the TC acquires when obtains the DHCP session). Wifi had the TC's IP as DNS server.

I changed Ethernet DNSs to TC's IP and now internet is amazingly fast.

Thanks for the info, I'll have to see if that is my problem as well. Mine sounds like something different though, because my file transfers from the TC over wifi to my MB are extremely slow. I don't think DNS Server settings could affect that. They are so slow that iTunes locks up if my library is on the TC and I try to use it over wifi.

 

[ayu61200]

If you click on the Wifi icon on the menu bar whilst pressing the alt key, what kind of wifi connection does it show? b, g or n? is the TC wireless set to 2.4 or 5Ghz? Are other local wifi networks running in the same channel as yours?

 

[jjk454ss]

If you click on the Wifi icon on the menu bar whilst pressing the alt key, what kind of wifi connection does it show? b, g or n? is the TC wireless set to 2.4 or 5Ghz? Are other local wifi networks running in the same channel as yours?

It says n. There are no other networks around to interfere. The TC is set to n(b/g compatible). I like to connect with my iPhone, or I'd set it to n only.

The problems with everything being so slow seem to have started after I plugged in an ext hdd to the usb on the TC.

 

[ayu61200]

It should be fine. The only thing I can come up with then would be trying only n to see if the problem persists, but it should be fine in the compatible mode too...

 

[jjk454ss]

I keep getting these errors when I wake my computer up that say server has been interrupted. It doesn't seem to affect anything, but it never used to say it. Is it because of Time Machine trying to run?

 

[ayu61200]

That's just means the network takes time to get established over wifi and Finder complaints the conection to the network drives is gone, just ignore it. It will dissapear alone when the connection comes back after waking up.

 

[spaceballl]

I found the reason of this weird behaviour, I'll post it here for anyone with the same problem to find out how to fix it:

The TC assigned a different DNS configuration to wifi connections than ethernet connections; Ethernet had 'real' ISP DNSs (the ones the TC acquires when obtains the DHCP session). Wifi had the TC's IP as DNS server.

I changed Ethernet DNSs to TC's IP and now internet is amazingly fast.

Yep there was just a thread on this - i was going to suggest to search, but you solved your own issue!