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.
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Reverse DNS - how to correctly configure for SMTP delivery
I started a new service and we need to send emails to our customers (new account confirms, etc).
My server is known as prod01.bidrodeo.com and resolves to 97.107.134.38 .
For reverse DNS, 97.107....
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answer
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Do internet standards require reverse DNS for every device?
The requirements surrounding reverse DNS are confusing! People frequently talk about everything breaking if reverse DNS is not present, and that sounds scary. Even in cases where applications don't ...
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Reverse DNS in a CIDR world
Reverse DNS seems to be strongly tied to class boundaries, what methods exist now that CIDR is the standard to delegate authority for a subnet? If multiple methods exist which one is best? Do you ...
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Multiple Reverse DNS Entries?
I'm a DNS noob, so here's a question:
Can a server have multiple reverse DNS entries? Or does one IP address just resolve to one DNS name?
Here is why I need this:
I have a number of sites hosted ...
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How does a Reverse DNS lookup work with regards to spam filters?
I have heard that most spam filters use a reverse DNS lookup on the originating IP address of the sending SMTP server (or something like that) as part of the verification process. I want to make sure ...
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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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What is reverse DNS?
I've lot of *.in-addr.arpa domains requests in my OpenDNS account. I know this should be normal and it's about reverse DNS.
I've been reading here and there but still I can't really get how it works ...
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Is it bad to have the reverse DNS for two IPs point to the same domain name?
I am in the process of setting up a new server for my web application (the site will be moved, it is not for load balancing or the like), which has a different IP address from my existing server. My ...
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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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sshd warning, "POSSIBLE BREAK-IN ATTEMPT!" for failed reverse DNS
Whenever I SSH somewhere I get something like this in the logs:
sshd[16734]: reverse mapping checking getaddrinfo for
1.2.3.4.crummyisp.net [1.2.3.4] failed - POSSIBLE BREAK-IN ATTEMPT!
And it ...
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Reverse DNS Lookup from the Command Line
I'd like to get a list of all domains pointed to a certain IP address. Is there a way to get this information from the command line?
Nothing like "host", "nslookup" or "dig -x". Those return the ...
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Is it good practice or too draconian to reject mails from mailservers with no RDNS
I've recently dropped SpamAssassin and am now basing spam rejection on DNSRBL's, grey-listing and other basic tests and I'm wondering whether I should also block hosts that don't have a valid RDNS ...
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Apache httpd won't stop doing reverse DNS requests for clients' IPs
Obviously my Apache httpd instance is doing reverse DNS (RDNS, give me the hostname for this IP address) lookups for each incoming client connection's IP address. This is bad. Especially since ...
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Remote connection to MySQL server takes very long
I have a MySQL 5.0.75 server running on my Linux notebook to which I want to connect from another machine in the local network.
This connection takes 5-6 seconds:
mysql -h 172.22.65.101 -u myuser -...
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Finding all domain names that resolve to the same ip?
Lately I've been tracking a spammer on craigslist. I recently discovered that he's added a new technique to his arsenal, he registered a whole bunch of domain names but they all resolve to the same ip ...
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SMTP host name vs. domain in "From:" address vis-a-vis Email Deliverability
I'm trying to implement (or make sure that I'm correctly following) email sending best practices to improve deliverability, but the role of the smtp server's host name vs the domain name of the From: ...
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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
)
...
4
votes
2
answers
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setting the reverse dns for a email server
'm having some trouble with email on a dedicated server, with Windows Server 2008. I've reached the conclusion I have to setup reverse dns for the mail server.
The current setup is this:
The mail ...
2
votes
1
answer
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Wildcard DNS like "*-test.example.com"
Is it possible to set up a wildcard domain like "*-test.example.com"?
The main reason I'm asking is because I'm in the process of setting up Continuous Integration with Jenkins, and we'd like to ...
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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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2
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How to append a domain to a PTR resolution?
I have a bind9 server authoritative for my domain example.com. Forward resolution works, PTRs as well up to a point.
I currently have
254.10.10 IN PTR srv.
in my PTR zone for 10.x, which ...
127
votes
15
answers
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What's the reverse DNS command line utility?
What's the command to find the name of a computer given its IP address?
I always forget what this command is, but I know it exists in Windows and I assume it exists on the *nix command-line.
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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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4
answers
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Reverse DNS Setup for an IP with multiple domains
I am trying to clarify my Reverse DNS PTR lookup for a domain. I have a server with a single IP addresses and multiple accounts, all sharing that IP address;
My PTR is currently:
24.210.31.in-addr....
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3
answers
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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
...
7
votes
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answers
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How do I change reverse DNS on Google Cloud Compute?
How do I change reverse DNS on Google Cloud Compute?
I want to add reverse DNS to Google Cloud Compute and can't figure out howto do it.
I want to map 11.97.196.104.bc.googleusercontent.com to ns1....
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1
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Reverse DNS is not a valid Hostname error from MXToolBox
I can't send email messages from my server. However, I can receive email messages. I set up my server the exact same way I did many times which I've proven it works and it's pretty straightforward and ...
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How to configure bind9 to be a local DNS only with no internet access?
I want to configure bind9 to be a local DNS only with no internet access at all. So I have 5 PCs in my virtual domain xy.com. Within this domain there is no access to the internet.
The DNS server ...
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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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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 ...
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2
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Why SMTP Reverse DNS Mismatch Reverse DNS does not match SMTP Banner?
I have set rDNS to mail.simplyislam.biz for IP 178.32.48.104 with my hosting server and also in DNS control panel.
However, I am still failing this test
Result: SMTP Reverse DNS Mismatch Warning - ...
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5
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How do I configure reverse DNS for a SMTP server [duplicate]
We use iis 6 to send out emails for our website but some email addresses bouce backs. It only appears to be 2 addresses. There is at least 100 different email addresses sent to at the same time as ...
4
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2
answers
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Delivered to internal network by a host with no rDNS
Recently our emails started going to spam for recipients at Gmail and Yahoo mail.
I ran a SpamAssassin test, and have found the following:
pts rule name description
0.0 ...
4
votes
1
answer
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Hotmail/Outlook dumping apparently valid emails
I've written some software that operates a non-commerical contact list for clubs, where the server sends out admin mails to the entire club. The emails are received Ok on Yahoo, gmail, and AOL, but ...
4
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2
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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 ...
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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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DNS, should I be using A instead of CNAME?
I'm doing a big reshuffle of our websites and hosting, moving about 10 domains to a new server. In doing so I had to make some changes to the DNS, pointing all of the domains at the new server.
...
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4
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Does sending e-mail in the name of customers increase the risk of being marked as spammer?
We are developing a SaaS website application that lets users send invoices to their clients. Ideally, these e-mails should appear to be originating from our customers, so the sender e-mail address ...
2
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2
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ISPs and reverse DNS lookups
I read in easyDNS that, in order to set up reverse DNS, "The IP block must be delegated to our nameservers by your ISP." Is that always the case? What if you decide to host your name servers? Will ...
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3
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Reverse DNS does not match SMTP Banner [duplicate]
I'm new to this site but I have found many good answers on this site before. I have also searched for my actual question but I didn't found the answer or at least I didn't understand what should I do ...
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Domain whitelisting in Kubernetes DNS Service
Can I use Kubernetes dns service to whitelist the domains for my pods? I want to restrict the outgoing (egress) calls using Kubernetes dns service. if I can achieve this, can someone let me know the ...
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Postfix/Spamassassin can't determine rDNS too often
I am running a Debian 7.9 server with Postfix 2.9.6 and Spamassassin 3.3.2.
One of the standard checks Spamassassin does, is to check for a rDNS record. I am assuming that it gets that info from the ...
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1
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Reverse dns for web/mail server with single ip
I have a single server with single ip running a web server, mail server and bind (all for a single domain).
In my DNS zone file I created A records for www.domain.com, mail.domain.com, ns.domain.com ...
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3
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Hotmail wants me to modify my SPF record
This is my current SPF record. It works well with gmail and yahoo but hotmail was ignoring. So i used their submit system and now they replied me with the text below.
This is my current spf
v=spf1 a ...
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Why create a reverse DNS record for every device that connects to a wireless network?
There's this network I connect to often. After some experimentation, I figured out that when you connect to the network, the DHCP server assigns you an FQDN that usually follows the scheme <your-...
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1
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Reverse PTR record lookup not working with dig
As mentioned here, having a Reverse PTR record is key for successful email sending and delivery from one's own server. In order to check if it's correctly set for my server, I tried:
dig -x 111.111....
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Reverse DNS record can't point to Domain name but it can point to IP [closed]
I am using parallels plesk for hosting my websites,
Some days ago I tried to send emails from my mail server and the mails were going to spam,So i tried spam assassin to detect whats wrong. Here is ...
0
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2
answers
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rDNS 'zone [xxx] has no address record (A or AAAA)
teaching myself some server tricks.
Getting trouble with bind9 on debian8.
named-checkzone pro.lan db.pro.lan.inv
zone pro.lan/IN: NS 'server.pro.lan' has no address records (A or AAAA)
my db.pro....
0
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1
answer
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Reverse DNS issue with Mailserver (Postfix) [duplicate]
My mail server is set to server.mailtuner.com, but when i try sending to a hotmail user, it goes into the spam folder.
Results on mailtester show the following reverse DNS issue: https://www.mail-...
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2
answers
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Some advise needed on how to setup reverse PTR on web and mail server
I'd appreciate some advise on how to run DNS with both httpd and mail running on the same server.
I have one server running on AWS, and i want to run both httpd and mail on it. Currently it just runs ...