krb5 commit: Add OpenLDAP advice to princ_dns.rst

https://github.com/krb5/krb5/commit/ecaf868e1abb443cd72a00956aeb71e18b71c4ba
commit ecaf868e1abb443cd72a00956aeb71e18b71c4ba
Author: Sam Morris <[email protected]>
Date:   Wed Sep 8 18:24:28 2021 +0100

    Add OpenLDAP advice to princ_dns.rst
    
    ticket: 9027 (new)

 doc/admin/princ_dns.rst |    9 +++++++++
 1 files changed, 9 insertions(+), 0 deletions(-)

diff --git a/doc/admin/princ_dns.rst b/doc/admin/princ_dns.rst
index b2db007..e558cd4 100644
--- a/doc/admin/princ_dns.rst
+++ b/doc/admin/princ_dns.rst
@@ -115,3 +115,12 @@ any key in its keytab when accepting a connection, rather than looking
 for the keytab entry that matches the host's own idea of its name
 (typically the name that ``gethostname()`` returns).  This requires
 krb5-1.10 or later.
+
+OpenLDAP (ldapsearch, etc.)
+~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+OpenLDAP's SASL implementation performs reverse DNS lookup in order to
+canonicalize service principal names, even if **rdns** is set to
+``false`` in the Kerberos configuration.  To disable this behavior,
+add ``SASL_NOCANON on`` to ``ldap.conf``, or set the
+``LDAPSASL_NOCANON`` environment variable.