On Jan 29, 2008 12:58 AM, Patrick W. Gilmore <patrick@ianai.net> wrote:
A general purpose host or firewall is NOTHING like a mail server. There is no race condition in a mail server, because the server simply waits until the DNS query is returned. No user is watching the mail queue, if mail is delayed by 1/10 of a second, or even many seconds, nothing happens.
Now magine every web page you visit is suddenly paused by 100ms, or 1000ms, or multiple seconds? Imagine that times 100s or 1000s of users. Imagine what your call center would look like the day after you implemented it. (Hint: Something like a smoking crater.)
There might be ways around this (e.g. zone transfer / bulk load), but it is still not a good idea.
Of course I could be wrong. You shouldn't trust me on this, you should try it in production. Let us know how it works out.
Andrew, IIUC, suggested that the default would be to allow while the check was performed. -Jim P.