DNS issue on vlan OR Not

RouterOS Beginner Basics
1

I have a fairly new PC that for some reason today can no longer resolve IPs. (on vlan11)
I can ping IPs, but nslookups dont work. Heck I can even remote rdp out to a wan IP.
I tried static and dynamic settings no difference, even unchecked ipv6.
Since the PC has wifi I checked the same vlan on wifi and no go. (vlan11)
I tried a different vlan and SURPRIZE I can browse and nslookup. (vlan30)
This is driving me nuts and I just want to make sure it has nothing to do with my MT router setup.
Just to make it clear other computers on vlan11 like the one I am using to type this, work just fine with all the same settings.
bamboozled???

2

I suppose that your new PC receives all the needed data from DHCP server? Does it have DNS server(s) set? On windows you can check it using ipconfig /all …

Can it access DNS server? In theory DNS servers should also accept TCP connections and you can check TCP connectivity by using telnet command (Windows by default has it disabled, to enable it, follow instructions here) by executing telnet <DSN server’s IP> 53 … if it just hangs there, it was able to connect. If it can’t connect (either because no service is listening on that port or access to that port is forbidden somewhere), telnet client will complain after a second or three.

You can’t really get any sensible answer from DNS server using telnet though, DNS protocol is binary … to do that, you’ll have to use nslookup.

3 
export hide-sensitive file=yourexport

:laughing: Couldn’t help myself…Sorry.

4

I think I have a graphic somewhere that shows a fist which then dissolves with only one finger remaining… :wink:

5

The interesting story on this one is the following facts.

  1. Problem PC
    a. PC nic card gets VLAN11 dhcp no problem
    b. Able to ping internet numbers
    c. Able to ping gateway, router and other network devices
    d. Able to access other vlan11 network devices by PC such as switches
    e. Unable to resolve internet names via nslookup
    f. Unable to browse through 4-5 diff browser types
    g. All drivers for nic card up to date (direct from manufacturer)
    H. Windows latest version all updated, file scanned etc…
    I. Separate wifi card on pc when connected to capac wifi on same vlan 11 shows same lack of name resolving functionality as wired card. :frowning:
    J. Able to wirelessly connect to other VLANS on same capac with full name resolving
    H. Able to change wired connection to any other VLAN on router and get full name resolving.
    I. Turning off both firewalls, macafee (free for one year on Dell) and Windows Defender, did not make any difference.

  2. Other VLAN PCs/Devices
    a. no problem full name resolving from other pcs on vlan11
    b. no problem full name resolving from other wifi devices on vlan11.

Free beer for the one that solves this riddle LOL. When you travel to Canada of course… ( none of that warm dark soup you call beer in the UK. Brexits my heart to think you don’t have nice ice cold canadian beer in your fridges :stuck_out_tongue_winking_eye: )