SBS 2011 Slow DNS over WiFi (LAN is fast) RRS feed

  • Question

  • Hi 

    I have an SBS 2011 DC server with DHCP DNS config (Server is the DNS server to the DHCP clients and has forwarders set to opendns for content filtering) connected to a network and a fibre router.

    Clients who connect through the LAN have excellent internet and network speeds (ran speedtest and the results were in line with our fibre line speed).

    Clients who connect to the wifi (2 Mac's, several iPhone's, several andriod phones and a Windows laptop) all experience slow network and internet speeds. The only time I can sort of resolve this is to set their DNS manually to google, but I don't want to because we are running a domain.

    The physical WiFi setup is an Archer D7 fibre router (New) with both the 2.4 and 5Ghz wifi setup (this connects to our 24 port hub and then back to the server). A Netgear range extender (New) for the 2.4Ghz and a TPlink AP (New) connected to a network point down the furthermost end of the office. The slow WiFi was present with the old/replaced WiFi equipment too.

    No matter which WiFi the staff connect on the internet and network speeds are slow (they also complain of the WiFi dropping with phone's going over to mobile data)

    I have run the BPA and it found no issues on the server and I have checked and triple checked the DNS on the server.

    I have similar physical setups (with different server) at other offices that do NOT experience these problems.

    So basically LAN is fast and WiFi is slow - I know it is something to do with DNS, but just can't work it out.

    Any help or suggestions are greatly appreciated.

    Tuesday, March 14, 2017 7:58 AM

All replies

  • Hi,

    According your description,the procedure from wifi clients to DC(DNS) seems to take the most time.

    1.Please check the wifi hardware make sure they are working fine.

    2.Use 'tracert YourDC' to check the  route to your DC,and which step takes the time.

    3.Or you could  perform a network captuer on wifi client.

    Here is the link of Windows network monitor:


    Best Regards,


    Please remember to mark the replies as answers if they help and unmark them if they provide no help. If you have feedback for TechNet Support, contact

    Best Regards
    Please remember to mark the replies as an answers if they help. If you have feedback for TechNet Subscriber Support, contact

    Wednesday, March 15, 2017 3:19 AM
  • Thanks. I will try this today.

    The hardware is new, but will try swapping out some equipment after these tests.

    Will let you know what happens.

    Thanks again.

    Wednesday, March 15, 2017 4:33 AM
  • Ok we have had some improvement by disabling the 5Ghz WiFi and updating the server's Ethernet driver.

    The other thing I checked was that all network cabling was at least CAT 5e - found one that was CAT 5 and switched it out and that user immediatly saw improvement.

    I'm going to leave it at that.

    Thanks again for your time and effort.

    Thursday, March 16, 2017 5:48 AM
  • Hi,

    Sounds good,if you have any other questions,please feel free to ask here.

    Best Regards
    Please remember to mark the replies as an answers if they help. If you have feedback for TechNet Subscriber Support, contact

    Thursday, March 16, 2017 9:16 AM