Hi!
> I know I have seen references to doing this, but I can't find them now.
> What I want to have is a secondary MX that, when it receives a rcpt to,
> attempts to query the primary, and do the following:
> 2xx - defer (I don't want ot accept if the primary is up)
> 5xx - reject
> 4xx or no response - accept. This is the only valid use of the backup,
> as I see it, anyway.
>
> I have tried
>
> defer message = The primary MX is up, please try them
> verify = recipient/callout=30s,no_cache
> domains = +backup_domains
>
> accept domains = +backup_domains
> endpass
> message = No such user
> !verify = recipient/callout=30s,defer_ok,no_cache,use_sender
What if your primary is unreachable for the sending host due to routing
issues? You wanna drop those also ? I mean, its not ALL spam thats going
to higher priority MXes...
Bye,
Raymond.
