I'll give that book a try and return to this thread with any remaining questions.
On Fri, Oct 15, 2021, 1:13 AM Viktor Dukhovni <postfix-us...@dukhovni.org> wrote: > On Fri, Oct 15, 2021 at 12:53:03AM -0500, Tyler Montney wrote: > > > Perfect, all of that makes sense. Here's 3 more: > > You might try the book by Patrick and Ralf, the basics haven't changed. > > > - The way I understand master.cf is that it spins up services. > > On demand, unless some idle instances of the service are already up and > running and waiting for requests. > > > For instance, the smtpd service to accept incoming connections on > > port 25, > > These spin up on demand and exit after a number of requests or when idle > too long. A lightly loaded system might not have any running much of > the time. > > > or qmgr that handles the various queues (like active and deferred). > > The qmgr(8) daemon runs indefinitely, until a "stop" or "reload". > > > For other services that wish to interact with say 'verify', how do > > they do this? > > By connecting to the service socket. > > > Would it be accurate to compare it to an HTTP routing table? > > The inetd(8) service and inetd.conf file is a better analogy. > > > They call postfix with the service name, and in turn get the > > executed command? > > No. They connect to the relevant public or private socket, and the > service is started if not already running or busy and the process limit > has not been reached. > > > - Why are Postfix manual pages for these services identical? > > - smtp/lmtp > > Same program implements multiple services. > > > - bounce/defer/trace > > Same program implements multiple services. > > > - Is there any documentation for the service 'relay'? > > It is an smtp(8) transport, see smtp(8) and ADDRESS_CLASS_README. > > For more basic background questions, let Patrick and Ralf earn some > royalties, and: > > http://www.postfix.org/OVERVIEW.html > http://www.postfix.org/BASIC_CONFIGURATION_README.html > http://www.postfix.org/STANDARD_CONFIGURATION_README.html > > and other documents at: > > http://www.postfix.org/documentation.html > > -- > Viktor. >
