Free Tools for IT Administrators

RBL Lookup
   
Enter domain name or IP addresses to lookup in the RBLs

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PTR Check
Enter a domain name or IP address to lookup reverse PTR record

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Mail Server Configuration Check
Enter a domain name to perform a series of tests to determine if DNS, PTR, MX records are setup correctly and domain is not black listed in an RBL

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Mail Server Availibility Check
Enter domain name to check if the mail server is accepting e-mails and point out issues that could cause email delivery from the internet

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MX Check
Enter a domain name or IP address to lookup MX records

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SPF Check
Enter a domain name to lookup SPF record

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Name Servers Lookup
Enter domain name for DNS Servers lookup

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Whois Info
Enter a domain name to lookup registration information

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IP to Country lookup
Enter an IP address to find its country location

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Ping
Enter an IP address to use to see the ping response

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Tracert
Enter an IP address or hostname to use to see the trace command response

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IP v6 to IP v4 converter
Enter an IP v6 address to convert to IP v4 equivalent

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IP v4 to IP v6 converter
Enter an IP v4 address to convert to IP v6 equivalent

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Your IP : 38.107.191.108  

PTR Check

Enter a domain name or IP address to lookup reverse PTR record

What is a reverse PTR record?

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PTR record or more appropriately a reverse PTR record is a process of resolving an IP address to its associated hostname. This is the exact opposite of the process of resolving a hostname to an IP address. Example, when you ping a name mail.somedomain.com it will get resolved to the ip address using the DNS to something like 192.168.1.5. Reverse PTR record does the opposite; it looks up the hostname for the given IP address. In the example above the PTR record for IP address 192.168.1.5 will get resolved to mail.somedomain.com.

Why do you need a reverse PTR record?

The most common use for looking up a PTR record is done by spam filters. Concept behind this idea is that fly by night spammers who send e-mails out using fake domains generally will not have the appropriate reverse PTR setup at the ISP DNS zone. This criterion is used spam filters to detect spam. If your domain does not have an appropriate reverse PTR record setup then chances are most e-mail spam filtering software will block e-mails from your mail server.

How do you setup a reverse PTR?

You would most likely need to contact your ISP and make a request to create a reverse PTR record for your mail server IP address. For example, if your mail server is mail.somedoamin.com then ask your ISP to setup a reverse PTR record 192.168.1.5 (your internet public IP address) in their revesre DNS zone. Reverse DNS zones are handled by your ISP even though you may have your own forward lookup DNS zone that you manage.

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