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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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Is it possible to set up a reverse DNS record on AWS for address from a different registrar?

I don't have control over the registrar for the domain we use but the elastic ip and domain have been registered to each other - now I need to set up a mail server on my EC2 instance and therefore be able to set up a reverse DNS record as well. Will…
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Do I need to Set-up PTR record in SPF Setting?

I have set-up the RDNS from my hosting provider for the ip address to resolve to "maximus.example.com". After that, do I also need to add the PTR records to the SPF Text details in my DNS zone file as well like this? v=spf1 include:_spf.google.com…
Neel
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Are PTR records added only by the ISPs that provide and manage the IPs?

I am administering a network with many locations and work with multiple providers I checked out with my DNS provider to change the PTR records for one of the IPs, they replied: Dear Sir, We can not modify the PTR records of the IP addresses that…
Eduard Florinescu
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server can't find XXX.in-addr.arpa: NXDOMAIN

I am facing a problem while configuring BIND DNS showing server can't find XXX.in-addr.arpa: NXDOMAIN while reverse dns check! everything works on forward DNS lookup but reverse DNS lookup fails. Here are my configuration files: named.conf options…
Ashwin Mekala
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ping -a sometimes returns host name and sometimes returns FQDN. Why? Does this mean DNS is corrupt somehow?

I have a Windows machine called abcd for example and it uses DHCP to receive an IP address (172.28.45.5 for example) When I perform ping -a 172.28.45.5 sometimes I receive abcd as the hostname. Sometimes I receive the FQDN, for example…
Blue Tongue
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Ping hostname returns another hostname in output : what does it mean?

When I ping the server sip3.voip-centrex.net, I get this output: PING sip3.voip-centrex.net (194.98.81.144) 56(84) bytes of data. 64 bytes from mpfrrelay.michaelpage.fr (194.98.81.144): icmp_req=1 ttl=50 time=35.7 ms 64 bytes from…
alci
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With regard to anti-spam practices, what exactly does a typical reverse DNS check look for?

My understanding is that a typical reverse DNS lookup will compare the SMTP hostname (provided in the EHLO/HELO command) of an incoming connection and verify that it matches the PTR record for the source IP the connection it is coming from. Is that…
Mike B
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Postfix & client IP reverse DNS

I explicitly added reject_unknown_client_hostname and several other reject rules to slow down SPAM in our server. So far that's working nicely. However, there is an important client that keeps getting rejected by our mail server, either because…
Mike Darrow
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BIND9 reverse DNS, /16 zone

I'm trying to set up a reverse zone for the entire 10.200.x.x/16 subnet. I've configured everything according to named.conf and several different blog posts, but no luck. Note that the A-records resolve correctly, the problem is reverse lookups. Can…
pauska
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Mac OSX Server 10.6 DNS Issues

The server was upgraded from 10.5 from 10.6, during the upgrade the Reverse Zones were lost so I tried to recreate these but found that it's best to delete all zones, definitions and start again. So I've started again and Reverse Zones are appearing…
dallasclark
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Create PTR Records from Existing A Records (Windows DNS)

I am migrating DNS zones (both forward and reverse) from Bind to Windows DNS. The reverse entries in the existing Bind server have not been maintained all that well for the static zones and I would rather not just import all the records. I have…
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How to confirm who is responsible for serving reverse DNS (PTR) requests an IP block?

Before anyone answers "ask your ISP" or "ask your hosting provider", please read in full. Scenario: I own a domain name mydomain.example, and a publically routed IP block (say 192.0.2.0/28) The NS records (GLUE) for this domain are configured at my…
rgb255_255_255
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sshd_config AllowUsers and IPv6

Have two servers communicating via ssh and crontab, a "master" and a "slave". Only the master can connect (execute command) on the slave. Authentication was done automatically (IPv4) thanks to master's ~/.ssh/id_rsa.pub added to slave's…
Déjà vu
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How do you know if reverse dns is setup correctly on your server

Total newb question I know, but I just want to be sure.
trustfundbaby
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How do you configure BIND to forward reverse DNS queries to another DNS server?

I've got 2 domains in my environment. One of them is an active directory domain for 'myproductionlab.local' at 10.60.0.0/16 Then I have a debian box running bind9 for a domain, 'mytestlab.local' I have added an entry into my named.conf.local: zone…
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