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Automatic IP Warmup

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    When your business is looking to accomplish any kind of sending, it is always good to put your best foot forward. The same can be said for IP reputation. Email Service Providers (ESPs) will be monitoring their incoming traffic, and IPs with no reputation doing an incredible amount of sending can be a warning flag for them. Mailgun has developed an automated IP warmup process that takes the guesswork out of the numbers game for you when it comes to email volume and warmup, and it only takes a few clicks to get you started on this! 


    Why should I warm up an IP?

    If a high volume of traffic is coming from a single IP that has little to no reputation, delivery issues are a possible outcome. This can range from messages being greylisted or throttled, to more severe issues like filtering of the incoming messages or including a block on the IP. A solid, positive reputation is crucial to a dedicated IP functioning properly. How can our customers avoid the negatives?

    The best way to introduce your traffic to an ESP is through a gradual but consistent increase. In this manner, an ESP will be able to determine that the traffic flowing through this particular IP is expected in both content and volume. Our automatic IP warmup process allows us to handle the numbers while you focus on sending your business's emails and monitoring how ESPs are handling your messages. At different message totals, we will automatically cap the sending on that IP. 

    What happens if you send over the daily allowed limit on the warmup plan? Our plan automatically takes care of that for you by rolling over additional traffic to either your other dedicated IPs on the domain or provided shared IPs. With this kind of feature, you have the flexibility to get your content out at the pace your business needs while also working to improve the reputation of your dedicated IP. 


    What does the warmup look like?

    Our team of email experts at Mailgun by Sinch has created a warmup schedule. This schedule will adjust the sending limits of the IP without any manual input on your behalf, acting as a sort of barrier or railing to allow for that gradual increase within a 24-hour period. You can see the breakdown of the schedule below:

    To borrow an example from our blog: let’s say in stage 1 you sent out exactly 100 emails every hour until all 1,000 emails went out.

    1,000 emails per day / 100 emails per hour = daily volume cap hit in 10 hours

    You basically sent the maximum daily volume of emails for stage 1 in about 8 hours, which means you have to wait a full 24 hours before you can move on to stage 2. Once that cap is hit, a full stop throttle is in place to prevent the IP from being overused. The 24 hour period starts with the first message that goes out. As an example, if you sent your first email at 10am and send 100 messages every hour, by 8pm, you would reach your daily quota. This means that the throttle on that IP will be closed until 10am next day.

    Now, on the flip side, if you don’t send the maximum volume of emails per hour, it could take you much longer to reach stage 2. Assuming you’re sending a lower volume per hour – something like 50 emails, and we still have the 1,000 email cap in the first stage:

    1,000 emails per day / 50 emails per hour = daily volume cap hit in about 20 hours

    The same volume of emails could take roughly 2 days to send, but you’re not in danger of hitting the daily cap for that stage. In this case, daily email volume and the 24-hour wait period between stages are mutually exclusive. Once you’ve sent out the 1,000 emails in stage 1, you will move on to stage 2 regardless of how many hours it takes you to send those emails (a 24-hour wait period still occurs).


    How do I get started?

    Once your Mailgun account is created, you can click on your username in the top right, scroll to "Send Settings," and select Dedicated IPs. Click on the "Add new IP" option to get started with your dedicated IP request.


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    Note: Please ensure the correct region is selected when creating this request. If your domains are on the US side of Mailgun, you'll select the US. If your domains are set up with Mailgun on the EU side, then please ensure you've selected the EU region. The account from this screenshot is a demo account that is on our Scale plan, which includes a dedicated IP request. If you have a dedicated IP included with your plan, the above is what you should expect. If it is not included, please refer to our pricing page for more information


    Frequently asked questions

    If Stage 2 is 2,500 emails, is that total cumulative to Stage 1's 1,000 emails, or is this starting from 0?

    Your sending will start at 0, so you'll need 2,500 emails once stage 2 begins in order to move on to Stage 3. 

    Is there anything I should worry about when it comes to deliverability if my sending isn't consistent (ie. only sending out announcements regarding seasonal deals)?

    If a dedicated IP is not sending consistently and with a sufficient volume, our advice is to re-warm ahead of time. If you suspect this might be the case, please let our Support team know and we can enable the warmup process during this time. 

    I saw the 50,000 number up above regarding sufficient sending. What if I don't intend on ever hitting that mark?

    Our recommendation is that you go through the warmup process up to the point where you're at the peak, consistent sending. Once this is achieved, you can let our Support team know, and we can remove the warmup plan for that IP. 


    Further resources


    Need Support?

    Our Support Team here at Sinch Mailgun is happy to help! Reach out to us in the Support section of your Mailgun Control Panel, and we'll be with you shortly!