"oops, try again later" is not what is happening when your mail server reboots. Email uses asynchronous protocols.

> "oops, try again later" is not what is happening when your mail server reboots. Email uses asynchronous protocols.

Wha...? How do you think my server receives emails while it's rebooting?

The sending server will automatically try to deliver the email again for a few days. If the receiving server is occasionally down, there will be a delay, but if it's not down for very long (many days) the email will eventually be delivered.

self-hosting is generally done on cloud vps providers (like ec2, digital ocean). Also, email is asynchronous. Email has a lot of retry logic built into it. You seriously don't think it behaves you think it does, do you? Imagine the amount of emails dropped :-)

> Email has a lot of retry logic built into it. You seriously don't think it behaves you think it does, do you? Imagine the amount of emails dropped :-)

Retries on the order of a few minutes, maybe. I think I've very rarely seen maybe a handful of retries, one a day, in certain cases (thanks to mailer-daemon notifications from Gmail). I don't imagine servers keep retrying for days on end beyond that (maybe internet outage was a poor example here though). Am I wrong? How long do retries go on for? Like imagine if you were on a trip when your server crashed. Now you miss emails for two weeks and you imagine that when you reboot it after coming back the senders will keep retrying? Is that really how it works? And if it does, would you really want to have that level of availability? You never have to worry about that kind of thing with a service provider, but as soon as you maintain your own server you have to constantly monitor it and be able to fix it ASAP.

I have been self-hosting my email for a few years now. (I use Zimbra BTW) Whenever the server goes down for whatever reason, the sending SMTP will retry. Each server has their own configuration, and can be changed by the adminsitrator, but it's usually a few days. As an example, on their default configurations, Exim will retry every 24h, and give up after a week. IIS will retry every 2 hours and give up after 2 days.

nobody says you have to self-host on your personal pc using your home connection.

I thought that was the point, since you didn't trust other people not to be mining your data? If it's another person's machine then they could just read your emails...

No, you self-host because you retain the ownership and control of your data. You choose service providers whose main business is not to snoop your data. For example, if you choose a server from amazon ec2 or linode or your local vps provider, they are not going to snoop your data because they are in the business of selling servers and not mining all your servers.

Okay, different question: any reason to believe the government isn't making them share dumps of their servers behind your back? I thought paranoia about the government reading your emails was the other huge reason to want this sort of thing in the first place.

If you're that worried then you can encrypt your server or data folder if needed.

What's the point though? Wouldn't the key need to be on the server if I encrypt it? Otherwise how can my mail server even work?