PTR is a type of record in DNS system used for reverse DNS lookups (IP address to hostname)

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Why multiple PTR records in DNS is not recommended?

I often read that using multiple PTR records in a DNS configuration is not recommended. However, the reasons are often vague, or not so obvious, naming: "it can cause problems", "can trigger ...
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How do I check a reverse PTR record?

I need to check a reverse PTR record to make sure that a script I have is sending emails which will actually received by my users and not incorrectly marked as spam. I understand that the ISP which ...
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How important are PTR records for Email Servers?

Does anyone know of any studies done to show how much email will be rejected if there is not ptr record for the SMTP banner name of an email server? Are reverse checks always done when enabled, or ...
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Reverse DNS records not registered when using DHCP

I've stumbled upon a strange behaviour with Windows machines, which seems to be fairly consistent between all Windows versions from Vista/2008 to 8.1/2012 R2; it doesn't happen instead when using ...
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How to setup PTR (Reverse DNS) at Godaddy DNS manager

My hosting provider already did PTR setup. Now i have to setup it at my DNS holder i guess. What am i supposed to do at my Godaddy account. thank you. my ip : 64.250.113.235 and you can check my ptr ...
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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 ...
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Importance of PTR records on nameserver IP's?

I have not yet experienced any DNS failures due to a missing PTR record, but am wondering: Is there any added value in having a valid PTR record on a nameserver IP-address?
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How to determine which DNS server has the authority to set rDNS (PTR records)?

or to re-phrase... How to determine to whom authority has been delegated to set rDNS? Background In a multi-tier environment, where a block of IP's is assigned, then further split and assigned ...
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how to add a REverse PTR Record on Amazon Route 53?

if i have the below ip 168.144.254.X and i would like to add a ptr record in amazon in the form of X.254.144.168.in-addr.arpa what should be in the name field and what should be in the value field ...
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What services require properly configured PTR records?

I manage a few DNS servers (Bind9, Windows Server 2008 R2) that are used internally. I have always taken the time to make sure that the correct corresponding PTR records were configured for Reverse ...
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How are DNS PTR records managed?

As I understand it, an IP address-owner can set up a DNS PTR record for his IP address to map the IP addresses to its host names. There are some things about this I don’t understand. I’ve managed ...
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SMTP Reverse DNS Mismatch

My dedicated server ns382087.ovh.net resolves to 46.105.98.72 and hosts multiple domain with several dedicated IP addresses. Each new IP address is added to /etc/network/interfaces Among them, the ...
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How to determine if my mail server is configured correctly?

Does anyone know of an online service (similar to the ones that tell you if a site is up or down) that can connect to a specified mail server and perform checks to see if it is configured correctly? ...
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Does a PTR record prove anything about the sender's email domain?

My outgoing mail server has problems reaching some recipients. This happened after we changed ISP for our dedicated IP address. I think it might be due to PTR records, but I cannot be sure. My ...
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3answers
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Moving from one ISP to another; DNS PTR question

We are going to be moving from one ISP to another in the next month or so, and I will be changing the TTL's down to 60 seconds on the DNS servers that I have authority for, but our current ISP has ...
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5answers
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DNS, PTR, Mail Server HELP!

I am not really sure which route to take. Here is my current setup. We host our web server on RackSpace Cloud (moved from EC2) Previously we hosted our own name servers, now we use RS (RackSpace) ...
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2answers
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PTR record (rDNS) for multiple domains on a shared IP address

I host multiple domains on a single IP address: cats.com A @ --> 10.20.30.40 A mail --> 10.20.30.40 MX @ --> mail dogs.com A @ --> 10.20.30.40 A mail --> 10.20.30.40 MX @ --> ...
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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.
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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 ...
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1answer
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Is it possible to set a PTR record for Github Pages hosting?

Icelandic domains (.is) require that their domains support reverse DNS, which means configuring PTR records on the hosting server. Is it possible to set up a PTR record for GitHub Pages site hosting? ...
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2answers
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Configuring PTR records!

One of our client requires PTR records to be configured. Their ISP does not support the same. Can I create a PTR record on my name servers for an IP owned by a different ISP?
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3answers
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DNS PTR record when domain on shared IP address

I own a typical shared IP hosting plan and domain. I can modify the DNS of the domain from the control panel. The mailserver shares the same IP address, so my typical DNS config is: www.mydomain.com ...
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1answer
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PTR record needed? Where?

I have a problem which I think can be resolved by adding a PTR record. Email isn't working for xx@example.com. I looked up the SMTP issues on mxtoolbox.com which returned the following: SMTP ...
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2answers
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PTR and A record must match?

RFC 1912 Section 2.1 states the following: Make sure your PTR and A records match. For every IP address, there should be a matching PTR record in the in-addr.arpa domain. If a host is ...
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1answer
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My ISP set up a PTR record for my mail server, but some places aren't seeing it

I have a VPS running Windows 2008 server with plesk 9, which I am using for email. I asked to my ISP to add a PTR record, which they did but my mails still droping into spam box. I have checked ...
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1answer
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$GENERATE'd records competing with real PTR records

I have a zone (1.168.192.IN-ADDR.ARPA) $GENERATEing PTR records from 1-254. However, I also have some custom PTR records, within that range, that are declared aside from the generate directive. ...
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How to add PTR record for a /16 IP block in BIND using $GENERATE directive?

I'm trying to reverse map a block of IP using PTR record to some special name so their usage can be easily reflected by a simple nslookup. For example, here's a nslookup result: # nslookup ...
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1answer
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PTR Webserver and Appserver

I'm a little confused about the setup of a PTR record for reverse dns lookup. We are hosted at Rackspace and we have a front end webserver and behind that an appserver. Users don't access the ...
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2answers
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How should I set up my PTR Record?

I am trying to properly set up my ptr record as I have noticed that some email notifications sent from my website have gone to spam for certian people, and I am having trouble figuring out exactly ...
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1answer
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SMTP DNS Validation with multiple mail servers behind multiple Public IPs

I know when a Mail server receives an e-mail, it performs a "DNS 3 way check" (I think this is also sometimes called FCrDNS) as a simply test against spammers. The way I understand it to work is as ...
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3answers
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Is the Reverse PTR record fine

I've checked my email headers at http://mxtoolbox.com which says it is ok. But I'm not sure. MY server's FQDN is host.tariffplansindia.com and for my server's IP( 23.239.30.81) the reverse PTR record ...
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1answer
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How to match PTR record with a different domain?

I am a bit confused about PTR records and how to set it up correctly. This is the current setup: A website: domain.com, on this website I have a mailaddress info@domain.com. On domain.com I have an ...
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A and PTR records and redundant Internet connections

Want to set up PTR record(s) to handle the following: Site with mail server (Exchange 2010) has three Internet connections, with the firewall handling load balancing. I know that if the Internet ...
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1answer
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Where did dedicated.abac.net. come from in my rDNS and PTR records?

So I followed this guide to the letter: http://docs.cpanel.net/twiki/bin/view/AllDocumentation/WHMDocs/RdnsForBind I did so for 3 domains. When I "test" the records and enter: host 64.150.176.81 on ...
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How to set PTR record on Windows Server 2008?

I'm having some problems sending out emails from my SMTP Server... apparently I need to setup the PTR record for Reverse-DNS Lookups. I have no clue how to do this. Some instructions point ask to ...
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What should my reverse DNS be for my inhouse email server?

So I have an inhouse exchange server for the domain visaustralia.com. (email addresses are email@visaustralia.com) And when checking the reverse DNS of my static IP address with ...
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How do I set up a reverse zone file?

I have this zone file in bind: $TTL 86400 mysite.net. IN SOA ns1.mysite.net. admin.mysite.net. ( 2006012008 86400 3600 604800 86400 ) ...
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1answer
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PTR records are not valid. but they should be!! - PTR quandary

I have a perplexing problem from my point of view. Not a mail server expert though so here goes; Using mail-tester.com, done a spam test for my mailserver and it's telling my PTR record is invalid, ...
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PTR record and dyndns

I have domain name at dyndns.com and set at home smtp server. I try send mail to other servers but get error: 550 We cannot accept email from IP 92.46.76.192 without a DNS PTR record. Contact your ...
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Discover server responsible for serving a PTR for a specific IP?

Just as the title reads: How do I discover what nameserver is the authoritative nameserver for PTR records for a specific IP?
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1answer
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What steps to do to set the DNS PTR record, is the IP in reverse in the name needed?

I had the following error: <xxxxxxxxxxxxxxxx@xxxxxxxxxxxx.de>: host yyyyyyyyyyyy.yyyyyyyyyyyyy.de[33.33.33.33] refused to talk to me: yyyyyyyyyyyy.yyyyyyyyyyyyy.de (mxeue106) Nemesis ESMTP ...
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1answer
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PTR record created, but not found

We are a small ISP, using linux DNS servers. Recently a client has asked us to create a rDNS zone for a specific IP address, which is used for a mail server. They keep getting message failures for ...
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1answer
888 views

Windows 7 PTR records with Cisco DHCP server

I would like to have my windows 7 clients register their own PTR records since I use a Cisco DHCP servers. DNS is Active Directory integrated. How can I go about doing so without setting up a ...
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1answer
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One server, one external IP, several virtual domains --> one PTR?

I've got some problem with ptr and domains. Here is situation: external ip: 123.123.123.132 domain1: example.com domain2: elpmaxe.net mailserver is on exim4. PTR 123.123.123.123 matches example.com ...
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Is this PTR record / DNS set up correctly?

Received the following error from a user: WARNING: Forward-DNS does NOT match Reverse-DNS. DNS is INCONSISTENT. Some users are having their email marked as spam. I looked in the PTR records and ...
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DNS and PTR for SMTP: shared IPs and subdomains

This question is similar to others about PTR and DNS for SMTP, but one specific aspect was unanswered: what if one machine does SMTP and HTTP on the same IP address. For example: SMTP at ...
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1answer
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PTR Record setup with separate incoming and outgoing servers [duplicate]

The situation: Even though SPF, DKIM, and the entire mail formatting is optimized to score 10/10 on mail-tester, many outgoing mails are marked as spam in yahoo and outlook. The primary server sends ...
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1answer
103 views

The correct PTR record in DNS

I'm confused with my DNS records. I own a domain (e.g. example.com).I've set A record for my SMTP server (e.g. smtp.example.com) for outgoing emails. The email address is (e.g. ...
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2answers
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Assist in diagnosing reverse dns mismatch

We seem to have an occasional issue, whereby mail is bypassing our first three MX records, and going to our 4th MX record. This is purely a backup, and we think that the reason it is skipping the ...
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1answer
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Postfix sending emails via multiple broadband lines

I have a site that send out emails from a postfix server. They have multiple broadband lines for load balancing and failover. I want them to be able to send out emails though both lines without the ...