Poor transfer speeds with Dlink Gigabit switch

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janplank

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I bough a Dlink 8 port gigabit switch from takealot the other day. My Laptop has a 1Gbit lan port and my NAS only 100Mbit. I bought a TPlink gigabit NIC for the NAS. The NAS server runs Openmediavault. I have a 10/100Mbit switch which served me good but transferring big movies took ages.
My transfer speeds between the laptop and NAS with the 100Mbit switch was around 8-9MB/s. Changing to the gigabit switch with 2-3MB/s transfer speeds with the same setup. Why is this happening? I've never seen this before?? Must all devices be 1Gb ports?
 
Are your cables of good quality?
 
Is the ethernet actually port running at 1G?
ethtool eth0 | grep -i speed (may need to install ethtool, not sure if omv includes it)

Are the cables Cat5e?
Jumbo Frame size in use?
 
lsheed_cn said:
Is the ethernet actually port running at 1G?
ethtool eth0 | grep -i speed (may need to install ethtool, not sure if omv includes it)

Are the cables Cat5e?
Jumbo Frame size in use?
Click to expand...

I am not sure. I thought it was all plug and play?
I'll use some pre-crimped cables and try again.
The LEDs on the switch shows amber for 100Mb & green for 1Gb speeds.
Surely the gigabit switch should still give me 8-9mb/s throughput if I still use the 10/100Mb port on the NAS?
 
As others have said, could be a speed and duplex issue. The Auto/Auto feature could not be negotiating correctly.
Also check your Ethernet cables... make sure that all 8 pins are terminated. If only 4 are used, you will not get 1Gb.

There is also an odd chance the backplane of the switch could be the cause.
 
You cant have some devices running gigabit and some fast Ethernet, if one device is 100meg then all other devices will be transferring at 100meg.

Also set all switches and PC's to auto negotiation.
 
It would be a good idea to upgrade to cat6 or cat6e cables. should fix your problem
 
Ive gotten 70-75MB/s (MegaBytes/s) When connecting two computers together and using DC++ as the FTP.
 
WihanVR said:
It would be a good idea to upgrade to cat6 or cat6e cables. should fix your problem
Click to expand...

Cat5e alone is enough for gigabit speeds, cat6 is reserved for 10G Ethernet, and there is no such thing as CAT6e, its CAT6a
 
Rickster said:
You cant have some devices running gigabit and some fast Ethernet, if one device is 100meg then all other devices will be transferring at 100meg.

Also set all switches and PC's to auto negotiation.
Click to expand...

I understand that, but why are my speeds now worse of than before. The switch is not configurable. I'll give it a go with my desktop and laptop which are both gigabit nic's.
I'll check the settings on my devices and see if something is going on there. What specifically should I look for?
 
If your NAS only has a 100MBit ethernet adapter, ~9MBps is about all you will ever get through it. I'm not sure how you evaluated the performance before and afterwards, but the rule of thumb is to divide the Mbps value by around 10 to get the MBps value, typically because there is a little bit of framing overhead with each byte (I believe, as I said, this is only a rule of thumb).

If I was you, I'd look at upgrading the NAS to add a Gbe port.

And yes, you should get better speeds between two devices that both have a Gbe port, with your new switch, than you would with the old one. Depending on the speed of the disks on either side, you should be able to get around 100MBps using Gbe.

To test if the switch is the problem, you can also try connecting two Gbe devices using a crossover cable, and manually assigning the IP address to each end (since you won't have a DHCP server on the network.) Alternatively, if you wait a bit, you should get a 169.254.*.* address on each end, and can then try to copy between those.
 
Rickster said:
You cant have some devices running gigabit and some fast Ethernet, if one device is 100meg then all other devices will be transferring at 100meg.
Click to expand...

Not true. If you have a gigabit switch, and two devices with Gbe ports, you will communicate between those devices at gigabit speeds, regardless of the capabilities of any other devices connected to the switch.
 
RoganDawes said:
Not true. If you have a gigabit switch, and two devices with Gbe ports, you will communicate between those devices at gigabit speeds, regardless of the capabilities of any other devices connected to the switch.
Click to expand...

Any proof to this?
 
Maybe it's just a dud switch? I got 8 of them in the office. One had poor speeds, swopped it out and now all is good.
 
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