![]() 2659 IN TXT “v=spf1 ip4:172.217.0.0/19 ip4:108.177.96.0/19 ~all” The Resultsīased on what the DIG command reports back, as of September 2017 the public Gmail IP address ranges currently include: The results come back here showing 3 different FQDNs: We need to issue another DIG command against that. We can see here that the results come back with the FQDN of _. (or you can use an online tool as shown in the following picture) You can do this with the following command: DIG txt The first step is to issue a DIG command to get the SPF record used for (TXT record) (Note – if you don’t have DIG on your computer, there are numerous online tools that support DIG commands that can be utilized with ease, such as ) Steps to find the Gmail IP address ranges So how can someone determine the public Gmail IP address ranges that Google seems to change from time to time? The steps below utilizing the DIG command will provide you this information. Using the DIG command to determine the IP address ranges used by Gmail can help to better determine which IP address ranges to allow through your firewall. ![]() While Google tends to publish this information in various tech notes on their webpages, the information on those webpages is usually outdated and not completely up to date. Setting your firewall up to limit outbound SMTP to ONLY those specific public IP address ranges, can help limit your exposure, and allows the email client to work properly without random error messages stating it couldn’t properly send outbound mail. Getting these public Gmail IP address ranges can easily be accomplished using the DIG command. When using a full (or fat) email client such as Outlook, Mail, or eM Client (instead of using web-based email) for sending and receiving email with Gmail based email accounts, it is important to know all the public Gmail IP address ranges used by Google for SMTP. In general, security conscious firewall administrators will limit outbound port 25, 465, and 587 traffic through the firewall to specific destinations and sometimes from specific internal sources as well – such as an SMTP relay server. ![]() In this article, we walk you through the steps to find the Gmail IP address ranges you need. ![]() Doing so can result in your organization’s public IP address getting blacklisted in a hurry if any of your internal devices get infected with malware, or viruses, that start sending out massive amounts of email spam from bots. If you’re like most firewall administrators, you dislike the idea of opening up port 25, 465, and 587 for outbound traffic to the -entire- internet. ![]()
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