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10GB Synology NAS only getting 1GB connection to 10GB Dlink DXS switch

Last Modified: 2018-12-03
I have recently purchased the following
Synology DS1817 NAS (not the + version, this version has 2 x built in 10GB NIC's & 2 x 1GB NIC's)
2 x Intel X540-T2 NIC's
1 x DLink DXS-1210-10TS 10GB switch

I installed the 2 x  X540-T2 in our Windows 2012r2 Hyper-V host. Each card has two ports. I have configured
all 4 ports as a team and connected each to the DLink DXS switch. All 4 connections are 10GB as expected - perfect!

Connecting the Synology DS1817 NAS I only get a 1GB connection. Local 2m CAT6 cable.

I raised a support case with Synology. Synology support got me to connect the 2 x 10GB NIC's together with a CAT6 patch lead
and connect the NAS to the DLink switch via one of the 1GB ports. Synology confirmed that the were getting 10GB communications
between the 2 x 10GB and concluded that the issue lay "somewhere else" on the network!

I have used tested 2m CAT6 cables from both 10GB NIC's to the Dlink DXS switch - both connect at 1GB
If I set the switch ports to 10GB I loose communication with the NAS.
All ports on the DXS are 10GB.

Anyone have any idea why, if the Synology DS1817 NAS is working correctly, I am not getting a 10GB connection to the DXS10 switch?
Thanks in advance

Watch Question

David Johnson, CDSimple Geek from the '70s
Distinguished Expert 2019

There are a lot of knock off cards floating around the marketplace.
It should be passive cooling and have Intel holograms. There is a problem with the cooling of these units, replacing the paste under the heat sinks help.

Using jumbo frames  or setting the MTU to 9000 helps. I've had better success with mellanox nic's


The Intel x540-t2 cards are from distribution with passove cooling. No issue with the cards as they get 10gb connection to switch.
Issue is only with Synology DS1817 NAS. This device is only getting 1gb connection even thought its 10gb port(s) are connected to 10gb DLink DXS switch.
hecgomrecNetwork Administrator

I will say you have to make sure on the NAS that these network cards are configured properly.

These cards can be use for load balance or line aggregation (trunk).  If these cards are set to operate in either mode you must match those settings in both devices.  Most likely this is your issue since you'll loose communication with the NAS when you force the 10G.

Also, you may try to test another set of cables... either 6 or 6a.  Note: Cat6 can accommodate the 10 GB but 6a is built for it!!


The DS1817 has 2 x 10GB NICS as standard. According to Synology 10GB should be available "out the box" when connected to 10GB switch with cat 6/cat6a cable. No load balancing or aggregation in place. I just changed the cable(s) to Cat6a but no change. DLink have responded with a request that I update the firmware on the DXS switch - link is to a version that does not appear to be on support website. I will be be updating this evening.


Thanks for the comments. The firmware supplier by DLink solved the problem. Frustrating as when I got to the correct person they knew about the issue. Shame they cannot publicise and save everyone a lot of time,
This problem has been solved!
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