On Mon, 28 Aug 2000 15:19:00 -0700, Adam Audette <[log in to unmask]> wrote: >We use passive probing for our lists (some of which have nearly >12,000 subscribers) and plan on using it for much larger lists soon >(over 150k). Is this a bad idea? Is it a big resource hog? Not if your server uses LSMTP and you have USE_LSMTP_MAIL_MERGE=1 in the site.cfg file. This makes LISTSERV handle passive probing as an internally generated mail-merge job which takes almost no extra resources. If you aren't using LSMTP then yes, there is a resouce impact.