Todd Vierling wrote:
A colleague asked me offlist about how to make a Sendmail secondary MX properly return 550 for invalid recipient addresses.
[snip] For those with an LDAP directory containing mailbox information, I'd recommend using sendmail's built-in LDAP capabilities. I've found it a good way to test for existence of mailboxes at border MTAs. My example (NOTE: I've pulled out the LDAP stuff from a rather complex .mc file, and it can be done in a more straightforward way without all of the other hacks I'm simultaenously supporting in my rulesets), LOCAL_CONFIG Kldap_rcpt ldap -b dc=example,dc=com -h directory.example.com -T<TMPF> -v mail -k (&(objectClass=inetLocalMailRecipient)(!(inetUserStatus=deleted))(!(inetMailGroupStatus=deleted))(|(mail=%0)(mailAlternateAddress=%0)(mailEquivalen tAddress=%0))) LOCAL_RULESETS # Check if local addresses really exist on central server. SLocal_check_rcpt R< $+ > $1 R$+ @ $=R $: $1 @ $2 $| $(ldap_rcpt $1@$2 $: <NOMATCH> $) R$* $| <NOMATCH> $#error $@ 5.1.1 $: 550 User unknown -- Crist J. Clark crist.clark@globalstar.com Globalstar Communications (408) 933-4387 The information contained in this e-mail message is confidential, intended only for the use of the individual or entity named above. If the reader of this e-mail is not the intended recipient, or the employee or agent responsible to deliver it to the intended recipient, you are hereby notified that any review, dissemination, distribution or copying of this communication is strictly prohibited. If you have received this e-mail in error, please contact postmaster@globalstar.com