Reverse DNS (formerly IP Whitelabel) allows mailbox providers to verify the sender of an email by performing a reverse DNS lookup upon receipt of the emails you send.
Reverse DNS is available for dedicated IP addresses only.
When setting up reverse DNS, Twilio SendGrid will provide an A Record (address record) for you to add to your DNS records. The A Record maps your sending domain to a dedicated Twilio SendGrid IP address.
A Reverse DNS consists of a subdomain and domain that will be used to generate a reverse DNS record for a given IP address. Once Twilio SendGrid has verified that the appropriate A record for the IP address has been created, the appropriate reverse DNS record for the IP address is generated.
You can also manage your reverse DNS settings in the Sender Authentication setion of the Twilio SendGrid App.
For more about Reverse DNS, see "How to set up reverse DNS" in the Twilio SendGrid documentation.
Retrieve all reverse DNS records
Base url: https://api.sendgrid.com
This endpoint allows you to retrieve all of the Reverse DNS records created by this account.
You may include a search key by using the
ip query string parameter. This enables you to perform a prefix search for a given IP segment (e.g.,
limit query string parameter to reduce the number of records returned. All records will be returned if you have fewer records than the specified limit.
offset query string parameter allows you to specify a non-zero index from which records will be returned. For example, if you have ten records,
?offset=5 will return the last five records (at indexes 5 through 9). The list starts at index zero.
- API Key
on-behalf-of header allows you to make API calls from a parent account on behalf of the parent's Subusers or customer accounts. You will use the parent account's API key when using this header. When making a call on behalf of a customer account, the property value should be "account-id" followed by the customer account's ID (e.g.,
on-behalf-of: account-id <account-id>). When making a call on behalf of a Subuser, the property value should be the Subuser's username (e.g.,
on-behalf-of: <subuser-username>). See On Behalf Of for more information.
The maximum number of results to retrieve.default: None
The point in the list of results to begin retrieving IP addresses from.default: None
The IP address segment that you'd like to use in a prefix search.default: None
The ID of the Reverse DNS.
The IP address that this Reverse DNS was created for.
The reverse DNS record for the IP address. This points to the Reverse DNS subdomain.
The users who are able to send mail from the IP address.
The username of a user who can send mail from the IP address.
The ID of a user who can send mail from the IP address.
The subdomain created for this reverse DNS. This is where the rDNS record points.
The root, or sending, domain.
Indicates if this is a valid Reverse DNS.
Indicates if this Reverse DNS was created using the legacy whitelabel tool. If it is a legacy whitelabel, it will still function, but you'll need to create a new Reverse DNS if you need to update it.
A Unix epoch timestamp representing the last time of a validation attempt.
Indicates if the a_record is valid.
The type of DNS record.
This is the web address that will be mapped to the IP address.
The IP address being set up with Reverse DNS.
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