... and on a -somewhat- related note: Does anyone here recommend 'premium' e-mail hosting, such as Rackspace E-mail? (http://www.rackspace.com/apps/email_hosting/rackspace_email/). What are the benefits of such services? I am trying to understand the benefits of these premium e-mail services to a postfix on a self-managed VPS.
One major advantage of premium hosting services (and other SaaS providers such as SendGrid) is that for outgoing mail, your mail will be delivered and not marked as spam/blacklisted/dropped silently.
Because of the low volume of outgoing mail from a VPS, it's very easy to end up on blacklists.
Wait, how does sending little emails can get your server blacklisted? Is it because they don't care about the small guy, or is there some technical reason ?
It's really about how much a false positive affects your IP's reputation.
When you are sending out a lot of email, recipients see a volume of mail. If a few of these get marked as spam, no big deal, you sent out 5,000 mails in an hour, of which 2-3 were marked as a false positive.
If you are running your own VPS you are sending out comparatively fewer mails so the decision on whether you are a spammer or not is made with a lot less information -- and most recipients will assume you are a spammer immediately.
It's mostly because you're not yet proved to be NOT spam. When you start a new mail server on an IP there's zero diference between a legimate email server and a spamhost. Your IP will not be in spamhaus and other blacklists, but you might get stuck in McAffee and other more enterpricey filters, especially if some other IPs in your subnet are known to send spam.
If you only need a small handful of email addresses, often the hosted service can provide those for a lower (or similar) monthly cost to that of a VPS (assuming you're dedicating the VPS to just email).
The blacklist issues others have pointed out are real. Some IPs are on blacklists and you will not be able to get them removed without an outrageous amount of leg work. Most of the premium email hosting places make sure they're not on those blacklists.
Personally, I use FastMail.fm. I've gotten the impression that if TSHTF, they'll fix it fast. The price is reasonable. They're not Google. When I get a website up that can't be served via static pages, I'll be going the VPS or other cloud service, but for email, I'm much happier leaving that to a premium provider.
I was on the wrong end of blacklisting situation and it was extremely frustrating. First, you don't know that your customers aren't receiving the emails. Second, you have very little clout in getting things cleared up. Third, it's just a huge PITA that wastes a lot of time.
I'm running a very small operation, but one bad instance of my IP being blacklisted prompted me to shell out the extra $3 /months to have Rackspace send my emails.
I have used pobox.com for years for email. They have excellent spam filtering. They also have excellent remediation for the few false positives I've had over the years. I can also only remember a couple of times they've actually been down that I have noticed, and I access my email fairly constantly (at home and via my phone)
