Many thanks for the reply. In fact I found a small workaround, which of course adds more text to the log file. But it serves the purpose.
smtp_header_checks /^Subject:(.*)/ INFO $1 Best Regards Dhammika Gunawardena On Thu, Jan 19, 2023 at 7:15 PM Wietse Venema <wie...@porcupine.org> wrote: > Dhammika Gunawardena: > > Hi > > I have setup smtp_header_checks to log subject lines in my mail log. > > However the issue is messages are truncated to about 50 characters. > > Is there any method to get the full Subject into log? > > I suspect that you would like to have no limit on the amount of > header text that will be logged, but that is not going to happen. > > All logging must be limited in size, so that it cannot be abused > to bloat buffers or to spam logfiles. This is not a hypothetical > problem: some logging systems are so inefficient that they use up > more resources than the entire Postfix mail system. > > If you want to log headers longer than 200 bytes, then I suggest > that you use a Milter (C/C++, Perl, Python, Rust, ...). Be aware > that Postfix limits all header content with header_size_limit > (default 102400 byes). > > Wietse >