Dns Problem?

RouterOS General
1

Hi,

I´ve RB1100 and I have configurated as hotspot with captive portal.
The problem is that clients can´t entry to some web pages. Sometimes, if I Flush Cache, then works, but other times not.
Using the same internet connection without Rb1100 there is no problems.

Regards

2

If you go to terminal please do the following

/ip dns print

It could be that DNS is timing out - OR your provider may be limiting the number of requests -
It could also be that you have an invalid setup of sorts

When this happens - you might also try to resolve domains on the Mikrotik itself

/tools ping

or just go to terminal and ping google.com or another domain that is timing out

3

Hi,
I am also having problem with mobile devices and DNS resolution since a couple of days.
Not sure about what changes that caused it, but the only thing I am sure about is that is an RouterOS upgrade from 6.32 to 6.33.3.

I have downgrade to 6.32, unfortenately it did not solve the problem so I decided to upgrade to latest release again.
Added debug logs to wifi connections but there is no trace of any errors in the logs, it just doesn’t works anymore for the devices mentioned below.

Failing devices:
BlackBerry Z30 x 1
iPhone 5 x 2 (IOS 6, different versions)
iPad (IOS 6)
Sony xperia 3 (Android, unknown version)

All devices is receiving ip-address and DNS servers from DHCP

All pc’s we have connected is working as expected, I also have a dd-wrt router connected via wifi and this is also working.

My router 912UAG-5HPnD is running as Home-AP

4

Hi,

this is dns print

servers: 8.8.8.8
dynamic-servers: 10.90.5.1,8.8.8.8,78.136.107.50
allow-remote-requests: no
max-udp-packet-size: 4096
query-server-timeout: 2s
query-total-timeout: 10s
cache-size: 12048KiB
cache-max-ttl: 6h
cache-used: 106KiB

Dns 10.90.5.1 comes from router that is above this router.
If I do ping from router to host, it resolve and reply ping.

Then, considering that it´s a hotspot network and there is many users, corld be thar web provider is limiting the number of requests?

Could I do something then?

Regards

5

servers: 8.8.8.8
dynamic-servers: 10.90.5.1,8.8.8.8,78.136.107.50
allow-remote-requests: no

That last line basically is making it so that the LOCAL system IS NOT answering requests for DNS
You might need to enable that - and then create the firewall rules as needed.

I will test in a lab tomorrowish - its after 2AM here - but I am thinking while waiting for this train to pass (using cell phone with voice to text here) that is the issue.

6

Hi

I´ve enabled allow-remote-requests but the problem continues

Regards

7

Hi,

the problem I had was also solved by reconfiguring static dhcp addresses for mobile devices.
Not sure why connected pc’s got the correct addresses (static assigned also) but none of the mobile devices.
So I learned that if one is using static dhcp addresses and reply-only on ARP specified MAC, do export the config and reload it after upgrade otherwise it may not work correctly.
Found the cause when one of my devices got wrong ip assigned to it.

Sorry for mixing this thread up with my issue

/franz

8

Hi! I have the same problem( can you tell me in more details how you fixed it?

9

Same as which one? Multiple setups were discussed in this topic. Do you use hotspot or not? Describe your actual problem in your own words, and export your current configuration (see my automatic signature below regarding anonymisation).

10

Hi! I had problem with dns resolving on mobile devices. I resolved it by turning of “Use Peer DNS” in the APN’s settings and by setting google’s dns addresses “8.8.8.8” and “8.8.4.4” in the DNS Settings