Wietse Venema: > The Postfix master daemon opens three sockets per master.cf entry: > the service endpoint (the first field in master.cf), plus one > socketpair. This single socketpair is used to receive updates from > all the child processes that implement the corresponding master.cf > service.
Additional note: your inet_interfaces lists two IP addresses, therefore the master daemon opens one socket for each IP address. This changes the calculation slightly. > The current stock master.cf file has 24 entries. One is a TCP service > and the remainder are UNIX-domain sockets. That corresponds with > one TCP socket and 71 UNIX-domain sockets. > > With older master.cf files, two of those UNIX-domain services used > to be FIFO services, That corresponds with one TCP socket, 69 > UNIX-domain sockets, and two FIFOs. > > Based on your count of 65 sockets, I suppose that your master.cf > file has 22 entries (one TCP service and 21 UNIX-domain services). > > System library routines may open other sockets or files, for example, > to talk to nsswitch.conf services. The Postfix master daemon has no > control over those sockets or files. > > Wietse >
