christian winter jprgeymazaz09de wietse venema wrote rolf e sonneveld due respect fail see stick dumptoafile technique era quadcore processors gigabit backbones etc cant simply use ldap queries smart caching results exactly bottleneck openldap client routines dont cache caching help sshole dictionary attack mail server cant cache nonexistent names sshole asks addition postfix smtpd nonpersistent processes implement caching nonpersistent ldap clients would store shared local cache might well run local ldap replica maybe helps point even microsoft exchange 2007 operate edge server naming relayonly mailserver role one installs local active directory instance adam active directory application mode 2003r2 feature gets filled subset ad data neccessary mail lookups happens noncontinuously might also worth consider mail systems ms provides active directory adam synchronizer one query agains standalone windows server maybe even dedicated network connection bandwidth issue instead raising load level global catalog servers chris thu 07 aug 2008 135059 0100 postfix making many queries ldap