On 08/06/12 23:41, Wietse Venema wrote: > This was discussed in my reply three weeks ago. > [...] > Maybe they installed a "security" "firewall" that mis-implements > SMTP PIPELINING.
Yes I see now that this is the same issue. To add some data points, for future googlers if nothing else. In this thread: http://tech.groups.yahoo.com/group/postfix-users/message/286239 "Curtis" writes that Lunarpages (which was previously mentioned in this thread, as lunarservers.com) and Bluehost show this problem and that he started seeing it in May. And I am seeing this with a third provider. Again, very recent development. All three of these providers use cPanel/WHM, as far as I know, that's all they have in common. It would not be surprising to me if this is a problem brought in by a roll out of a new cPanel/WHM version. If it is, a lot of people are going to be experiencing this over time. The trouble is, that the failure isn't obvious, and that it seems that postfix is more affected than other senders (perhaps other senders do not use PIPELINING unless there are multiple RCPT's or something). Obviously, the task for fixing the problem lies with those who caused it (be it cPanel/WHM, some flunky firewall, or a ham fisted admin) and not with postfix who i, but perhaps this will help people to find that point of responsibility.
