Hello everyone,
I am currently running a server with the Pterodactyl panel for various game servers, and it has been working great for several years. However, I would like to set up a system for Pterodactyl to send out password reset emails when necessary. I am considering using Mailcow on the same host specifically for this purpose. Currently, I am using an application named DDNS-Updater to automatically update all records on Cloudflare when my IP changes. While my IP doesn’t change often, it can happen; it occurred once this year. Would this pose an issue for a mail server? If the emails end up in the spam folder, it is not a major concern since they are only password reset emails. However, it is crucial that the emails reach the intended recipients.
Thank you.
Just an FYI, zoho has a free tier with SMTP outgoing and 1 address that would work perfectly for this.
Acronyms, initialisms, abbreviations, contractions, and other phrases which expand to something larger, that I’ve seen in this thread:
Fewer Letters More Letters DNS Domain Name Service/System IP Internet Protocol SMTP Simple Mail Transfer Protocol
3 acronyms in this thread; the most compressed thread commented on today has 6 acronyms.
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On incoming side of things:
In between your IP change, your script update your DNS record, and finally sender’s server gets the new IP address, you may lose emails coming to you. Most mail providers will eventually, at their chosen cadence and frequency, attempt to re-deliver the messages, so you might get them eventually on a delay. There is no way of knowing what you’re not missing in the event the sender’s server not retrying. Mails coming to you is delivered into folders per your configuration, and should not end up in spam because of your IP change.
On the outgoing side of things:
Every IP address has some reputation attached to it. Residential addresses tends to score lowly because of people getting virus/malware and become part of a bot net to spam. As you’ve got no control over the IP address you’d receive from your provider, there’s no guarantee if you will receive a clean IP or not. Worst case scenario here is you might end up with a blacklisted IP, and your mail never gets accepted (or silently discarded) by receiver’s mail server. You may also run into SPF record needing the IP address but you can probably get your DDNS script to update this as well or, maybe just use an A record.
If your intention is to receive emails, it might work, but you might miss a message or few.
If your intention is to send mails, it is cheaper and easier to just get a transactional mail provider and pay pennies per thousand mails, and never worry about it.
If your intention is to make a full fledged mail service with send and receive… it’s just not worth the hassle and headache.
You need to create an MX record in the DNS zone of your domain. Something like:
@ IN MX 10 my.zome. @ IN MX 20 server1.my.zome.
You can create 1 MX record or more. 10 and 20 server priority for input mails.
Then you need to create an spf record. There are several options here. For example
allows you to send emails from A domain records, then from MX domain records and prohibits from all other hosts.
Theoretically, you can only create an SPF record with A but without MX and dont create MX DNS records. Although I have not tried this configuration.
This is the minimum set after which you will get into spam, but at least the letters will reach.
You also need to make a PTR record to avoid spam folder, but this is not possible on a dynamic IP.
If A and MX point to the same server you do not need the MX record.
Quite a few mail providers will also just blacklist all dynamic IPs in general.
I would recommend sending the mails via a smarthost (i.e. some authenticated SMTP connection).
I also have mailcow behind a dynamic in. I wrote a script that updates my cloud flare dns entries as soon as it detects that the ip changed. https://github.com/tinkermesomething/scripts-stuff/blob/main/cloudflare_DNS_updater.sh
I then use online services to check if they’re likely to get marked as spam
New Lemmy Post: Can i use mailcow on a dynamic IP with DDNS-updater for my usecase? (https://lemmy.world/post/9518022)
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