On Wed, Feb 19, 2020 at 10:02:46PM +0000, Eric Wilkison wrote:
> Our virtual alias files are script generated and updated periodically.
> I had considered adding a map for each user for each of the domains.
> However, we have about 80 domains. That times our 30k users and we'd
> have almost 2.5 million aliases. Seems like a very large list that
> could cause performance issues under load. Would you agree?
No. You're not likely to see any significant performance difference.
That's why database tables are indexed. Yes, there's a small
logarithmic cost factor, but it won't matter in practice.
But I also recommend strongly against aliasing every user into every
variant domain. That just buys your users multiple copies of every spam
message, because spammers will treat each address as a separate
recipient.
Instead, allow users to opt-in to additional domains as needed,
and maintain a list of actual registered aliases, rather than
a machine generated cross-product.
> Doing more research yesterday I came up with another possible solution
> I'd like to get your opinion of. What do you think of using
> smtpd_command_filter to dynamically update the recipients.
A gross hack. Don't go there.
--
Viktor.
