Reverse DNS
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
GET /v3/whitelabel/ips
Base url: https://api.sendgrid.com
This endpoint allows you to retrieve a paginated list of all 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., ?ip="192.").
You can use the limit query parameter to set the page size. If your list contains more items than the page size permits, you can make multiple requests. Use the offset query parameter to control the position in the list from which to start retrieving additional items.
Authentication
- API Key
Headers
The 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.
Query String
limit sets the page size, i.e. maximum number of items from the list to be returned for a single API request. If omitted, the default page size is used.
The number of items in the list to skip over before starting to retrieve the items for the requested page. The default offset of 0 represents the beginning of the list, i.e. the start of the first page. To request the second page of the list, set the offset to the page size as determined by limit. Use multiples of the page size as your offset to request further consecutive pages. E.g. assume your page size is set to 10. An offset of 10 requests the second page, an offset of 20 requests the third page and so on, provided there are sufficiently many items in your list.
The IP address segment that you'd like to use in a prefix search.
default: NoneResponses
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.
Retrieving paginated results
To perform a request for the first page of the paginated list of all reverse DNS records using the default page size, you can omit the limit and offset query parameters:
If you want to specify a page size of your choice, you can use the limit query parameter. Assume you want a page size of no more than 5 items per request, to retrieve the first page you can use the limit parameter without specifying an offset:
If you want to retrieve items beyond the first page, you can use the offset parameter as follows. Assume you are still working with a page size of 5 as determined by your limit query parameter and you have more than 15 items. To request the fourth page of items, you can use the offset parameter to skip over the first 15 items, i.e. you start retrieving items starting after the first three pages of 5 items each:
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