Infrastructure
Cold email infrastructure: domains, mailboxes and DNS, provisioned and capped
Cold email infrastructure is everything on the sending side: separate sending domains, the mailboxes on them, SPF, DKIM and DMARC records, and the caps and monitoring that keep them healthy. Dooxout provisions domains and mailboxes through its registrar integration and runs a preflight check before launch. The platform warns and recommends, and you decide.
What cold email infrastructure includes
Email infrastructure has four layers, and a gap in one cannot be made up by the others.
| Layer | What it is | What Dooxout does |
|---|---|---|
| Sending domains | Domains you send from, kept apart from your main brand domain so that sending trouble never reaches it. | Recommends look-alike names, checks availability and the registrar quote, and registers a domain only after a person approves the spend. |
| Mailboxes | The inboxes that send and receive. Each is a sender identity with its own history and its own daily cap. | Creates hosted mailboxes through the registrar integration, or connects your own Google, Microsoft or SMTP and IMAP mailboxes. |
| DNS authentication | SPF, DKIM and DMARC records that prove a message really comes from your domain. | Checks the records before the first send and flags what is missing. |
| Caps and monitoring | Daily limits per mailbox, domain and workspace, plus a watch on bounces and complaints. | Starts new mailboxes on low caps that rise with age, pauses on bounce and complaint thresholds, and shows mailbox metrics. |
Sending domains and mailboxes
Mailbox providers judge a message partly by the reputation of the domain it comes from. That is why cold email goes out from separate sending domains and not from the domain of your main site.
Cold email mailboxes
Each mailbox is one sender identity with its own caps and history. Dooxout can create hosted mailboxes for you, or connect your own: Google and Microsoft with the provider sign-in, or any mailbox over SMTP and IMAP. Replies are read over IMAP into one inbox.
DNS: SPF, DKIM and DMARC
SPF lists the servers allowed to send for a domain, DKIM signs each message and DMARC tells receivers what to do when checks fail. Dooxout checks the records before the first send. For setup details, read SPF, DKIM and DMARC for cold email and the full infrastructure guide.
Caps by mailbox age, and domain rotation
A new mailbox has no sending history, so it starts on a low daily cap and the cap rises with the age of the mailbox. The defaults are conservative and editable. Dooxout shows the numbers in the console and promises no schedule, because mailbox providers do not publish one.
Dooxout has no warm-up network. It limits volume and watches the results: sending pauses automatically when bounces or complaints pass a threshold. Read why in Cold email without warm-up.
Spreading volume across domains
A campaign can send from several sender identities in rotation, so no single mailbox carries the whole load. The sizing is plain arithmetic: divide the volume you want per day by the cap per mailbox. With an assumed cap of 30 a day and a goal of 300 a day, you need ten mailboxes spread over a few domains. Your real caps will differ.
How Dooxout provisions domains and mailboxes
- 01
Recommend
You or the SDR agent work out how many domains and mailboxes your target volume needs. The agent only recommends.
- 02
Check
Dooxout checks that each domain name is available and shows the registrar quote.
- 03
Approve
A person approves the purchase, inside the budgets you set.
- 04
Provision
The domain is registered, DNS is set and mailboxes are created, with passwords stored encrypted.
- 05
Cap
Each new mailbox starts on a low daily cap that is yours to edit.
- 06
Preflight
Before the campaign launches, a preflight check looks at DNS, the list and a test message.
The SDR agent recommends and never buys
The built-in SDR agent works out how many domains and mailboxes your volume needs under the current caps, suggests names, estimates the cost from the registrar quote and marks what you already have. The result is a recommendation card with a button into the order wizard.
Calls that register a domain, create a mailbox or spend money are refused for the SDR agent at every autonomy level, and a person completes the order. See AI outbound sales for the whole agent flow and security for how the limits are enforced.
The preflight check before launch
Before a campaign starts, preflight runs checks with no side effects and returns blocking items and warnings.
- SPF, DKIM and DMARC records exist for the sending domain.
- The sender identity is verified.
- The audience is scrubbed against suppressed addresses, and the verification status of the list is shown.
- Many leads without recorded consent trigger a warning.
- A test message from each sending mailbox goes through the deliverability check. See email deliverability.
A failing check blocks the launch. A person with the right to override can launch anyway after a warning, and the override is written to the audit log. The agent cannot override.
You own the decision
The platform warns and recommends, and you decide. On your own mailboxes or Amazon SES, SparkPost or Elastic Email account, it shows the risks of a cold list and asks you to confirm responsibility once. The one rule you cannot turn off is suppression of addresses that unsubscribed or complained.
Where to go next
- See unit billing on pricing and connectors on integrations.
- Drive it from your own agent with the email MCP quickstart.
- Run it for clients with agency workspaces and the white label cold email platform.
- Read the blog or return to the home page.
Infrastructure questions
What is cold email infrastructure?
It is everything on the sending side of cold email: separate sending domains, mailboxes on them, SPF, DKIM and DMARC records, daily caps per mailbox and monitoring of bounces and complaints.
How many mailboxes does one domain need?
Mailbox providers publish no such number, so Dooxout claims none. It divides your target volume by the per-mailbox caps that apply and shows how many mailboxes and domains that takes.
Does the SDR agent buy domains or mailboxes?
No. The agent recommends domains, mailboxes and an estimated cost, and a person makes the purchase. The agent has no permission to buy, whatever autonomy level it runs at. See AI outbound sales.
Can I use my own Google Workspace or Microsoft 365 mailboxes?
Yes. Connect them with the provider sign-in or over SMTP and IMAP. For cold lists the platform recommends its own mailboxes and small volumes on yours, and asks you to confirm responsibility once per source.
Is there a warm-up network?
No. New mailboxes start on low caps that rise with age, and sending pauses when bounces or complaints pass a threshold.
Plan your sending infrastructure with us
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