Questions tagged [dns]

This tag should only be used when it's about configuration of DNS on an on topic network device. Any general DNS service related questions are off topic.

Filter by
Sorted by
Tagged with
0
votes
0answers
4 views

School internet stops working when I change my DNS [on hold]

On my laptop I have my DNS servers set to 1.1.1.1, and 1.0.0.1 (Cloudflare DNS). However, when I connect to my schools network my internet stops working completely. I am aware that they are using the ...
0
votes
0answers
6 views

Expected delays accessing server via IP locally via DNS locally and globally [on hold]

I would like to know the expected delays (if any) in accessing a server in the same network and via the internet. Hypothetically I am on the local network and my IP is 10.16.140.74 I access a ...
0
votes
0answers
20 views

Why smtp.gmail.com may be resolved to different IP addresses on different machines? [on hold]

I'd like to understand why the domain same name may be resolved to different IPs. For example, I ping smtp.gmail.com from machines in different counties. I may get something like this. 172.217.195....
0
votes
0answers
10 views

How to configure a server running on MS Windows to route an IP via intranet/internet dynamically? [closed]

I apologize if the title might be incorrect. The crux of the problem is: 1. I have an application that runs on client machines throughout a hospital and can even be used remotely by doctors. 2. This ...
0
votes
0answers
6 views

How can i configure Unbound to use Microsoft Virtual Adapter [closed]

I need a light DNS and i found Unbound. It work fine with ethernet adapter, but i need that it work with WiFi adapter (resolve queries from wireless devices). I use a program to create a hotspot to ...
1
vote
1answer
32 views

DNS expire-entry-timer has negative affect on ASA using FQDN ACL

I have a Cisco ASA using FQDN egress ACLs for a host that changes IP addresses every 10 mins (Apple APNS IP address pool). As soon as the TTL expires for the addresses, my internal server requests a ...
0
votes
0answers
19 views

In what TCP/IP layer that DNS looksup happen? [duplicate]

When sending an http request from browser to www.example.com to map that domain name to IP address in which layer application layer or Internet layer that DNS looksup happen. It want IP address to set ...
0
votes
1answer
32 views

LAN to WAN IPv4 address mapped to LAN server through NAT Rules or other

I need to set a rule that allows me to connect BOTH from OUTSIDE the LAN (from the "internet" to the Internal server at IPv4 address 10.64.0.50 via port 22, by running ssh://1.2.3.4 -p 22; AND From ...
1
vote
1answer
48 views

How does a DNS response reach a client behind a NAT?

How does a DNS response reach a client behind a NAT? I'm talking about DNS queries using UDP for transport with a server that is not in the same network as the client. Does the NAT correlate the ...
1
vote
1answer
31 views

Why does www DNS record propagate faster than @? [closed]

I've recently had to move a DNS ownership from one DigitalOcean account to another. During this process I've noticed that the www A DNS record propagates a lot faster than the @ A DNS record. Why ...
1
vote
0answers
27 views

Trying to understand how DNS works [closed]

I try to run a tightened down machine security wise, and I was running the application network monitor program "SmartSniff", and I noticed DNS calls to port 53 out to a website I had visited in the ...
1
vote
0answers
12 views

Who determines a premium domain name? [closed]

Nearly all domain registrars have premium price tags against domain names that have one or two words. But whom is initially putting the high price tag on these domains? Is it ICANN, an invisible ...
0
votes
1answer
28 views

Dynamic DNS and VPN [closed]

I have a few PCs/services that I want to access remotely, which are inside a VPN and gets assigned local IP addresses using DHCP. How can I setup dynamic DNS to access the PCs on their internal VPN ...
3
votes
3answers
2k views

How WANs work and why it is it bad to run DNS and DHCP on a router?

I have some networking questions about isolating networks and why it's bad to run DHCP and DNS on a router and should be run on a server. Question 1: What is the purpose of the WAN interface and how ...
-1
votes
3answers
32 views

ACL for DNS clarification

I do not understand why the second ACL is needed if all I want is to ensure all networks use a certain DNS server (for example 192.0.2.1) access-list 112 permit udp any host 192.0.2.1 eq domain ...
1
vote
0answers
41 views

How to configure PowerDNS to return different IP based on client subnet [closed]

Our business network runs all over the country. In an effort to provide better, more localized service, I'd like to configure our PowerDNS to return different IP's based on where the client is (by ...
3
votes
2answers
3k views

What is IP-over-DNS tunnelling?

What is IP-over-DNS tunnelling please? I have seen this term used in the context of a captive portal. The idea was to redirect clients to the local web server and to force the DNS (?). It was ...
1
vote
0answers
108 views

Customized captive portal with external DHCP server [closed]

I am stuck in one issue for which I need your help on this. Actually its bit complex to explan about my situatuion but I will try my best. I am working on customized captive portal on arm processor ...
1
vote
0answers
198 views

DNS not resolving through VPN

Looking for some help with our Office's VPN that I can't seem to solve... I am trying to remote desktop to the Work PC from Home PC via the DC ASA 5506-x VPN. I can only connect to the Work PC with ...
2
votes
1answer
369 views

Fortigate - Redirecting subdomains only?

I'm trying to figure out a way to have our Fortigate 60C redirect certain subdomains but not block complete access to the domain. E.G. I want to block update.microsoft.com but I don't want microsoft....
1
vote
0answers
130 views

Cisco IP SLA HTTP request with frontdoor VRF

I am trying to use a IP SLA for HTTP on my Cisco ISR 4321 router to check if a website is reachable. The challenge is that I need to do that in a frontdoor VRF. I have configured ip name-server vrf ...
1
vote
2answers
328 views

How are packets routed based on IP and how are those routes acquired?

Good day all, this is my first question here, be gentle in judgement Background: At university, we are covering Network Routing Protocols. Having possibly found 2 issues with current routing ...
0
votes
1answer
94 views

How is a lost DNS query handled [closed]

If a DNS query gets lost along the way to its destination, is nothing done about it? In my networking class, my lecturer said that DNS runs on UDP. I verified this in Wireshark by doing nslookup for a ...
0
votes
2answers
752 views

Wireshark - capture all packets for HTTP request

I want to launch a HTTP request to a website I've never visited before. I would like to pick up all of the packets related to this request; so DNS packets, TCP packets, et cetera. Is there a way to ...
2
votes
3answers
525 views

connect a cisco router to the internet through a cable modem

The router gets an External IP address via DHCP from the Cable modem Clients inside the network get an IP address from Router's DHCP server I can ping that the external IP address from a client inside ...
1
vote
1answer
47 views

How do I find the IP of the DNS server that respond for a specific domain name?

So as the title says I want to get the IP of the DNS server that respond when I'm trying to reach a specific domain, using bash commands. If I understood it right, when I'm trying to reach www....
1
vote
1answer
49 views

Quanta switch not resolving addresses

I've got this brand new Quanta T3048. I've configured the VLANs we need but it came to my attention that the switch won't resolve any address even though I've set it (according to the configuration ...
0
votes
1answer
85 views

It's not showing the DNS why it is called reverse IP lookup?

I have searched a lot but I didn't get the reason that even after giving the IP address it never shows the DNS. If it doesn't give the DNS then why it is said to be reverse IP lookup?
0
votes
2answers
657 views

Why do I capture all DNS queries from everyone in the network when I port forward port 53 to my computer?

I'm seeing some things in Wireshark I can't explain. My setup is as follows: A router with a single global IP doing NAT for the devices behind it. I am also behind it with my computer. I port forward ...
1
vote
1answer
185 views

Access internal webserver with domainname points to external IP

We have a webserver on our LAN. Externally, we can use the public domainname (let's say business.com) to access the website. Internally, we need to use the local IP. We also want to use the public ...
1
vote
0answers
123 views

Different DNS resolution for same domain name [closed]

I am getting different DNS resolution for www.google.com. When I am using Google Public DNS i.e 8.8.8.8 then by using nslookup then it is giving IP address of Non-authoritative answer: Name: www....
1
vote
1answer
321 views

Can I ping a specific site without DNS server information? [closed]

If I clear DNS cache and remove DNS server information, how can I ping to a specific site?
1
vote
2answers
1k views

How to force users on my LAN to use a specific DNS server using ARP poisoning?

I'm attempting to force all hosts on my LAN to use a specific DNS server to filter certain material, however I'm running into problems. I've had problems in the past trying to configure my router's ...
1
vote
1answer
32 views

TZ205W DNS Issue

I have a firewall that is setup but need to have all users inside the network to use a preset dns server. While I know that I can set up this in the DHCP it does not stop a user from changing it in ...
0
votes
2answers
58 views

How can a public DNS server know the hostname of a machine on a private network [closed]

Example: a home LAN a simple SOHO router (both DHCP and DNS server at 192.168.1.1) 2 client machines (192.168.1.2 and 192.168.1.3) Is it possible for the Google public DNS server located at 8.8.8.8 (...
0
votes
1answer
84 views

Iterative queries of a default DNS server

I have just started to study networks and I have a confusion about what happens when a default DNS server does iterative queries to other DNS servers to resolve a name in an IP address. I am very ...
4
votes
1answer
215 views

How are IPv4 Addresses provided uniquely to domains?

this question has been bothering me for sometime and I've yet to receive a clear answer (it bothers me whenever I go to sleep). I would like to receive expert answers on this matter. Who mainly ...
3
votes
3answers
221 views

Can I see what happens when I run a DNS query?

My understanding is that when my computer wants to resolve a host name, it will ask the DHCP-assigned DNS servers first. If those don’t know, it goes and asks the ‘root servers’ who then defer to ...
0
votes
1answer
50 views

SRV Record for Service X [closed]

I've got a quite common question, which I can't find an answer for. Is it possible to create a SRV Record for any possible service I'm running? For example: I want webinterface.example.com to ...
-1
votes
1answer
30 views

Is it possible to convert a public IP and port to a DNS? [closed]

Must be said, I'm a complete ignorant on these matters. Is there a way or service so I can take and IP address and its port and make it a DNS? Is it possible or am I doomed?. Thank you.
0
votes
1answer
53 views

WHOIS request with nodejs package failing [closed]

I'm trying to do a bulk whois lookup of around 7000 domains. I use the node js package whois. This worked while I tested with individual domains. After I made a bulk request for batch of 50 domins, ...
3
votes
1answer
160 views

rate-limit dns queries on HP procurve 8212zl

I had ast week the situation that a user accidentally got our DNS server to its knees by sending over 270K DNS queries to our dnsmasq. I was looking for a reliable method to prevent this Happening in ...
1
vote
1answer
404 views

Tracert getting timeout on second packet consistenly

I'm on a vpn and tracing to virtualmachines that live in the VPN Server. I've been experiencing slow queries, when they should be fast. below is what the trace is returning. I'm curious as to why the ...
0
votes
1answer
131 views

resolving IP address to FQDN effectively [closed]

We use Netflow to control traffic, when i want to resolve the IP addresses from netflow's outside destinations list, i get local google cache server's IP address, never the web sites that users has ...
1
vote
0answers
24 views

Should static IPs be set on the DNS/DHCP server, the host, or both? [closed]

Assuming a pretty regular business setup, when assigning static IPs for servers to use, should they be assigned on the DNS/DHCP server? Should they be configured individually on the hosts? Or should ...
3
votes
1answer
267 views

ASA as a local DNS resolver

I have an site to site VPN access configured by ASAs. My remote site needs to connect to the domain through the tunnel which will required DNS located on the main site. I would like to use DNS server ...
7
votes
3answers
5k views

Why is DNS an application layer protocol?

The main role of DNS is to translate Domain Names to their corresponding IP adresses, so why is necessary to be an application layer protocol? I think that DNS is an application layer protocol ...
0
votes
2answers
112 views

Is DNS geo-redundant if my traceroute to each NS shows the same location?

Some providers employ BGP anycast for their NS servers. As a user, when doing a traceroute, many may show an identical location for both servers, for a given client. When he.net used to anycast ...
2
votes
1answer
652 views

Is it possible to set up (geographic) anycast on the Internet?

The top level DNS-servers use geographic anycast. Is it possible to set up geographic anycast on your own (DNS) servers on the Internet? The top level DNS-servers use geographic anycast. Is this set ...
2
votes
2answers
943 views

Preferred anycast paths for DNS with Quagga BGP

Background and goal Am setting up high availability DNS servers based on Unbound. Both DNS servers has in reality twelve BGP sessions against different routers but to make this easier only one router ...