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Questions tagged [reverse-dns]

Reverse DNS lookup is the determination of a domain name that is associated with a given IP address using the Domain Name System (DNS) of the Internet.

Reverse DNS lookup or reverse DNS resolution (rDNS) is the determination of a domain name that is associated with a given IP address using the Domain Name System (DNS) of the Internet.

Computer networks use the Domain Name System to determine the IP address associated with a domain name. This process is also known as forward DNS resolution. Reverse DNS lookup is the inverse process, the resolution of an IP address to its designated domain name.

Source: Wikipedia.

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How to configure Reverse DNS (PTR) records correctly for multiple domains on a single IP

I run a Virtual Private Server on which I host a number of websites using a single IP address. I need to configure Reverse DNS for each domain. Is this possible and what is the best way to go about this? My server is running Cpanel/WHM and is…
Luke McCallum
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Reverse DNS Delegation from ISP

I get a /29 Delegated to me from Verizon(Fios) and I got them to delegate rDNS to my Name servers, I Notice that with some systems that it works and is able to get my PTR record, but on some it isn't able to get the PTR. Is this just a issue with…
Jacob
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Should my dedicated static IP address point to my domain?

I purchased a dedicated static IP address from my hosting company to host my domain name. The IP will point to me domain when I ping it. However, when I conduct reverse DNS lookup, my dedicated IP points to somewhere else - other domain. when I…
need-help
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Slow connect on ssh on Ubuntu

I've recently installed Ubuntu 10.10 as a second OS on my desktop, but I'm having a strange problem: it takes several tens of seconds to connect to other linux machines via ssh. On Windows, I have no such problem, it connects instantly. So, again,…
evilpenguin
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Apache: allow from domain without using reverse lookup

I want to allow access to a folder from a "domain name" instead of IP address in apache. Now, allow from accepts domains as arguments, but I think it also does a reverse DNS lookup to cross check (which is good but too strict for me). Is there a way…
JP19
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Configuring a PTR record in domains.google for an SMTP server

I've found several threads related to this, but they are all very dated so I want to get some clarification. I use an AWS ec2 instance with an elastic-ip, I've set up an SMTP (sendonly) mail-server using postfix on ubuntu 18.04, and I manage my DNS…
David N
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How do I configure reverse DNS for a 6to4 site?

I'm using 6to4. How do I configure reverse DNS for my site? It's a Linux server, I'm using freedns.afraid.org and am not running bind.
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How to check for the existence of deep subdomains even if the intermediate ones don't exist?

Suppose that test.example.com don't exists and gives NXDOMAIN when runnning dig on it , but i know that subdomain.test.example.com exists and gives NOERROR when doing the same, is there a way to check that a deep subdomain exists even though the…
mehdi nejjari
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Who is responsible to set up reverse DNS (PTR) for a domain, the DNS host or the MX host?

I have the dns for a domain on GoDaddy and the MX configured for Gmail. All set up ok with spf, dkim and dmarc, and all passes all online tests, beside: intodns.com reports this error for the domain and marks it as severe: Reverse MX A records (PTR)…
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rDNS issue in Cloudflare and AWS ec2 instance

I have installed centos7, whm/cpanel and mailwizz on amazon ec2 instance, managing DNS through cloudflare.com. Everything is fine i have issue with rDNS even i have created PTR records in Route53 and WHM. WHM still shows following issue with PTR in…
Wasif
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PTR not showing in dig request

I am trying to set up a PTR for reverse DNS so that mail that gets sent from me scripts doesn't get blocked due to reverse DNS failure. I beleive my zone is set up correctly, however me "thinking" it's correct and "knowing" it's correct are 2…
Zak
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Windows AD DNS is automatically adding PTR records for CNAMEs and I want this to stop

Preface: I am not a Windows admin. I am a Linux admin. I have a Windows 2016 server with AD DNS that handles internal DNS forward and reverse lookups. Somewhere, somehow, some process is automatically adding PTR reverse lookup records for CNAMEs.…
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Postfix setup with different domain name, reverse lookup and SPF

I would like to set up Postfix properly to serve multiple virtual domains while complying to all standards and being able to enable security measures like SPF. The server has the hostname server.domain.tld. Postfix has mydomain set to…
StackExchange42
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Why Gmail's SMTP server Reverse lookup does not match

I am reading about setting up SMTP server and almost all articles suggest to ensure that the SMTP server's name has a matching reverse lookup (PTR) entry in DNS. However, When I casually checked the gmail settings, none of its smtp servers have a…
slayedbylucifer
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Why does SSH report "reverse mapping checking getaddrinfo failed" even when PTR record is set?

I'm trying to setup a cluster using a private network on subnet 10. One machine has two interfaces, one to connect to the regular network and the other to connect to all the nodes on subnet 10. This CentOS 6 machine (let's call it "zaza.domain.com")…
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