How important are PTR records for Email Servers?

Posted by Kyle Brandt on Server Fault See other posts from Server Fault or by Kyle Brandt
Published on 2009-12-09T15:02:27Z Indexed on 2010/04/04 17:33 UTC
Read the original article Hit count: 597

Filed under:

ptr

|

dns

|

reverse-dns

|

email

|

smtp

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 is it sometimes configured so if an spam program considers an email 'iffy', the reverse check is done?

© Server Fault or respective owner

Related posts about ptr

How important are PTR records for Email Servers?

as seen on Server Fault - Search for 'Server Fault'
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 is it sometimes configured so if an spam program considers an email 'iffy', the reverse check is done? >>> More
DHCP and DNS on none AD 2003 Server PTR is updating but no A records

as seen on Server Fault - Search for 'Server Fault'
I have a strange issue, I have a DHCP and DNS server running in a non AD environment, on Windows 2003 server. I setup DHCP to update DNS A and PTR records even if the client doesnt request it, but I only see PTR records updated, the A records are not created at all. The domain is "local" forward zone… >>> More
Importance of PTR records on nameserver IP's?

as seen on Server Fault - Search for 'Server Fault'
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? >>> More
TTL for PTR records on Windows 2003 Server DNS

as seen on Server Fault - Search for 'Server Fault'
When I look at the TTL (Time to Live) for PTR records (Reverse Lookup Zone) on one of our Windows 2003 DNS servers I see some are at 15 minutes, others are at 20. They have "Delete this record when it becomes stale" checked. These PTR records are for workstations that get IPs from Windows DHCP… >>> More
Maddening Linked List problem

as seen on Stack Overflow - Search for 'Stack Overflow'
This has been plaguing me for weeks. It's something really simple, I know it. Every time I print a singly linked list, it prints an address at the end of the list. #include <iostream> using namespace std; struct node { int info; node *link; }; node *before(node *head); node *after(node… >>> More

Related posts about dns

Master/Slave DNS setup vs. rsync'ed DNS servers

as seen on Server Fault - Search for 'Server Fault'
We currently have primary and secondary DNS servers on our corporate network. They are setup in a master/slave type setup, where the slave gets its DNS information from the master. I'm trying to figure out what the real advantage is for the master/slave setup instead of just setting up an automated… >>> More
Updating Windows DNS records from a remote windows DNS server

as seen on Server Fault - Search for 'Server Fault'
Does anyone know if it is possible for a windows 2003 DNS server to update the records for a domain so that it contains all the records of a domain of of a remotely based DNS server? Im almost certain that doesn't quite explain the problem so I shall illustrate with an example: We have two offices… >>> More
OpenVPN DNS: VPN DNS stomping local VPN

as seen on Super User - Search for 'Super User'
I've finally noodled with OpenVPN enough to get it working. Even better, I can mount samba drives, ping network machines through the TUN device, etc - it's all great. However, I'm noticing that if I have the directive: push "dhcp-option DNS 10.0.1.1" # Push our local DNS to clients Then some of… >>> More
Random DNS Client Issue with BIND9/Windows Server 2003 DNS

as seen on Stack Overflow - Search for 'Stack Overflow'
Within our office, we have a local server running DNS, for internal related "domains", (e.g. .internal, .office, .lan, .vpn, etc.). Randomly, only the hosts configured with those extensions will stop resolving on the Windows-based workstations. Sometimes it'll work for a couple weeks without issue… >>> More
DNS Tools - DNS and Few of its Concerning Terms and Tools

as seen on Article City - Search for 'Article City'
A DNS or Domain Name System lets you locate computers on a network or the Internet TCP/IP network by domain name. The DNS server sustains a database of domain names or host names along with their cor... [Author: Daisy Osbaldo - Computers and Internet - April 02, 2010] >>> More