Ben Rosengart:
> Dear all,
> I am trying to resolve some LDAP issues, and I've been asked about
> Postfix's connection management behavior. How many concurrent
> connections to a given LDAP server will proxymap(8) open?
One proxymap process should make zero or one LDAP connection per LDAP
configuration file. By design it uses the same LDAP handle for all
queries that resolve to the same LDAP configuration file.
There are as many proxymap processes as needed to handle the query
load. A new proxymap process is created when a client process wants
to look up something, and all proxymap servers are busy (this is
an over-simplification, as a client will reuse its proxymap handle
for a limited time).
> When does
> it close a connection, and when does it open a new one? I checked the
> man page, but it didn't go into this kind of detail.
I don't know when (if ever) an LDAP or *SQL connection is closed
other than by process termination. As for connections between
proxymap clients and servers, that has changed over time. Many
connections between Postfix daemons are controlled by ipc_idle,
ipc_timeout, and ipc_ttl, but some daemons have their own because
their requirements differ. For example the queue manager can't
afford to wait 3600 seconds.
Wietse
