Managing TXT Records
A TXT (text record) record contains supplemental information for a host. For example, if you have a sales server that serves only North America, you can create a text record stating this fact. You can create more than one text record for a domain name.
Use TXT Records for SPF
SPF (Sender Policy Framework) is an anti-forgery mechanism designed to identify spam e-mail. SPF fights e-mail address forgery and makes it easier to identify spam, worms, and viruses. Domain owners identify sending mail servers in DNS. SMTP receivers verify the envelope sender address against this information, and can distinguish legitimate mail from spam before any message data is transmitted.
SPF makes it easy for a domain to say, "I only send mail from these machines. If any other machine claims that I'm sending mail from there, they're not valid." For example, when an AOL user sends mail to you, an email server that belongs to AOL connects to an email server that belongs to you. AOL uses SPF to publish the addresses of its email servers. When the message comes in, your email servers can tell if the server that sent the email belongs to AOL or not.
You can use TXT records to store SPF data that identifies what machines send mail from a domain. You can think of these specialized TXT records as reverse MX records that e-mail servers can use to verify if a machine is a legitimate sender of an e-mail.
SPF Record Examples:
site.utexas.edu. in txt "MS=ms43561293"
site.utexas.edu. in txt "v=spf1 include:amazonses.com ~all"
Add a TXT Record From Within Your DNS Zone – Quick Start
- After logging in to the Grid Manager, navigate to the DNS zone in which you will create a TXT record.
- For instructions on navigating to the DNS zone of your choice, open the Managing Host Records page and follow steps 1 through 7 in the “To add a Host record from within the zone - quick start:” section.
- To add TXT record:
- Click the down arrow to the right of the Plus button to the left of the central pane.
- Select Record and then TXT Record.
- The Add TXT Record > Step 1 of 3 window will appear. NOTE: Notice that the zone “Infoblox1.utexas.edu” is already next to the Name section. This is because we drilled down into the DNS zone rather than adding this entry from some other location within the DNS tab.
NOTE: In most cases, the Name field will be left blank. Most TXT records in UT DNS zones are created for a domain whose name matches the selected zone. The appliance automatically adds the domain name (the same as the zone name) to the TXT record. If you wish to have the TXT record associated with a specific host, rather than the zone, you can enter the hostname in the Name box.
- The Name box is left blank because this record is for the “infobloxtest1.utexas.edu” DNS zone rather than a specific host.
- Key in the desired text – in our example we are adding an spf text record.
- Add comment (optional).
- Click Next.
- d. Click Next in the “Add TXT Record > Step 2 of 3” window e. Click Save & Close in the “Add TXT Record > Step 3 of 3” window.
Modify And Delete TXT Records
When you modify a TXT record, you can change the information you previously entered in the General tab. You can also enter or edit information in the *TIL, Extensible Attributes and Permissions tabs. For information on modifying and deleting resource records, see Modifying, Disabling, and Deleting Host and Resource Records.
For instructions on how to access Infoblox Online documentation such as the Administrator Guide, review the following document: Accessing Infoblox Documentation.