Re: [exim] unblocking gmail

On Wed, 12 Nov 2008, Randy Bush wrote:

| is there an efficient hack to double map the inbound ip to see if it is
| google or yahoo?

Others have sugested the spf plan. But if you simply want to check the
DNS hostname, then add something like this to the ACL statement:

!hosts = *.google.com : *.yahoo.com

As I understand it, if your config is already doing DNS lookup for the
connecting IP, then the above line will not trigger an extra lookup, as
the data is already cached in the exim process.

If however you're not already doing DNS lookups, then the above line will
cause them to be done.