Questions tagged [domain-name-system]
The Domain Name System, usually referred to by the acronym DNS, is a hierarchical, distributed database where the keys are domain names. Questions involving publicly accessible domains should include the real, Fully Qualified Domain Name (FQDN)
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AD DNS update for Samba client works for initial registration, fails renewal refresh of record
We have a large AD domain with three Windows Server 2022 DCs. DNS registration and renewal works with Windows domain members. I do not have control over the DCs (although I can access them for ...
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Domain Name Service (DNS) resolving Content Delivery Network (CDN) name
We have contracted a company to provide the new web server, and they use a company called Vercel to provide infrastructure for the site. They demand that we make the DNS for the site a CNAME which ...
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Support for CNAMEs in the pfSense DNS Resolver
Some background
I have a home network built on a NetGate 1100 with pfSense. This has been running well for a couple of years with IPv4 only. I have upgraded it now to pfSense 25.07.1
With an IPv4 ...
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How to forbid a domain to send emails? (Prevent spoofing.)
We have a few domains, which are not expected to send emails, therefore I would like to know if there is a way to effectively forbid those domains to send emails to prevent spoofing my company various ...
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File uploads fail when outbound Internet is restricted to specific IP addresses [closed]
I have a CentOS 7 server where outbound Internet is restricted using iptables to specific external IP addresses.
For example using Perplexity’s IP addresses:
sudo iptables -A OUTPUT -d 104.18.26.48 -j ...
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Postfix reverse DNS fails with DNSSEC resolver when there's a lame `in-addr.arpa` DNS zone delegation
I'm running Postfix 3.10 on an Ubuntu 24.04 server, with these settings in /etc/postfix/main.cf:
smtpd_client_restrictions =
# previous entries omitted for brevity
warn_if_reject ...
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How to set DNS for incorporating Email to mail.domain.org as well as domain.org?
NOTE: I wanted to ask this on StackOverflow but they state that DNS questions must be programming related so this doesn't quite fit that bill.
We have a bunch of domains on a server.
Typical DNS for ...
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Sudden issues with subdomain resolution to reserved IP
I've been hosting a static site via github for a few years on the domain shown. Recently I added a number of sub domains to reserved IPs on my network.
s01.pixeloven.com
d01.pixeloven.com
w01....
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Exchange Hybrid Split DNS
Our internal domain is domain.local, and external is domain.com.
Typical split DNS situation. My question is how do people typically handle this?
We are about to start our Exchange migration, and ...
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Active Directory DNS - how to create internal records for accessing external web sites
I am trying to use Active Directory DNS to create "easier" to use URLs for staff.
enroll.domain.org --> https://aka.ms/mysecurity
reset.domain.org --> https://passwordreset....
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What are the benefits of storing a hostname in a DNS NS record, instead of the IP?
This question builds on Why don't NS records contain IP addresses?.
I understand that a domain nameserver - say ns1.com - stores NS records as mappings domain-to-hostname. If a client wants to get ...
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DNS lookup fails even though an A record exists in Oracle Cloud DNS for it in the public zone
I have an OCI tenancy with a compute instance in the public subnet.
I purchased a donraikes.com domain through godaddy.com.
I associated donraikes.com with my tenancy by creating a public zone in the ...
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Why does Apple have many PTR records and others have none? [closed]
I am investigating reverse DNS (PTR) records and how they are used today.
For example stackoverflow.com resolves to 104.18.32.7 and that IP has zero PTR records (neither does the domain's other IP).
...
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NetworkManager-run dnsmasq doesn't pickup upstream servers from .conf file
NetworkManager-run dnsmasq doesn't pickup upstream servers from .conf file if I remove dns= from NetworkManager connection config
I am running WireGuard VPN server on a VPS and want to avoid DNS leaks ...
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Unbound Cache Stats Not Increasing - still Showing Same Hits/Misses After Days
We configured Unbound on a RHEL-based server ( RHEL 7.9 ) to provide DNS caching. Here’s the relevant part of our /etc/unbound/unbound.conf:
server:
chroot: ""
verbosity: 1
port: ...
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