[1372] added IXFR specific log messages

src/bin/xfrout/xfrout.py.in

@@ -383,34 +383,41 @@ class XfroutSession():
                     auth_rrset.get_class() != zone_class:
                 continue
             if auth_rrset.get_rdata_count() != 1:
-                # TBD: log it.
+                logger.info(XFROUT_IXFR_MULTIPLE_SOA,
+                            format_addrinfo(self._remote))
                 return Rcode.FORMERR()
             remote_soa = auth_rrset
         if remote_soa is None:
-            # TBD: log it.
+            logger.info(XFROUT_IXFR_NO_SOA, format_addrinfo(self._remote))
             return Rcode.FORMERR()
 
         rcode, self._soa = self._get_zone_soa(zone_name)
         if rcode != Rcode.NOERROR():
             return rcode
         try:
+            begin_serial = get_soa_serial(remote_soa.get_rdata()[0])
+            end_serial = get_soa_serial(self._soa.get_rdata()[0])
             code, self._jnl_reader = self._datasrc_client.get_journal_reader(
-                zone_name, get_soa_serial(remote_soa.get_rdata()[0]),
-                get_soa_serial(self._soa.get_rdata()[0]))
+                zone_name, begin_serial, end_serial)
         except isc.datasrc.NotImplemented as ex:
             # The underlying data source doesn't support journaling.
-            # Fallback to AXFR-style IXFR.
-            # TBD: log it.
+            # Fall back to AXFR-style IXFR.
+            logger.info(XFROUT_IXFR_NO_JOURNAL_SUPPORT,
+                        format_addrinfo(self._remote),
+                        format_zone_str(zone_name, zone_class))
             return self.__axfr_setup(zone_name)
         if code == ZoneJournalReader.NO_SUCH_VERSION:
-            # fallback to AXFR-style IXFR
-            # TBD: log it.
+            logger.info(XFROUT_IXFR_NO_VERSION, format_addrinfo(self._remote),
+                        format_zone_str(zone_name, zone_class),
+                        begin_serial, end_serial)
             return self.__axfr_setup(zone_name)
         if code == ZoneJournalReader.NO_SUCH_ZONE:
             # this is quite unexpected as we know zone's SOA exists.
             # It might be a bug or the data source is somehow broken,
             # but it can still happen if someone has removed the zone
             # between these two operations.  We treat it as NOTAUTH.
+            logger.warn(XFROUT_IXFR_NO_ZONE, format_addrinfo(self._remote),
+                        format_zone_str(zone_name, zone_class))
             return Rcode.NOTAUTH()
 
         return Rcode.NOERROR()

src/bin/xfrout/xfrout_messages.mes

@@ -178,3 +178,34 @@ on, but the file is in use. The most likely cause is that another
 xfrout daemon process is still running. This xfrout daemon (the one
 printing this message) will not start.
 
+% XFROUT_IXFR_MULTIPLE_SOA IXFR client %1: authority section has multiple SOAs
+An IXFR request was received with more than one SOA RRs in the authority
+section.  The xfrout daemon rejects the request with an RCODE of
+FORMERR.
+
+% XFROUT_IXFR_NO_SOA IXFR client %1: missing SOA
+An IXFR request was received with no SOA RR in the authority section.
+The xfrout daemon rejects the request with an RCODE of FORMERR.
+
+% XFROUT_IXFR_NO_JOURNAL_SUPPORT IXFR client %1, %2: journaling not supported in the data source, falling back to AXFR
+An IXFR request was received but the underlying data source did
+not support journaling.  The xfrout daemon fell back to AXFR-style
+IXFR.
+
+% XFROUT_IXFR_NO_VERSION IXFR client %1, %2: version (%3 to %4) not in journal, falling back to AXFR
+An IXFR request was received, but the requested range of differences
+were not found in the data source.  The xfrout daemon fell back to
+AXFR-style IXFR.
+
+% XFROUT_IXFR_NO_ZONE IXFR client %1, %2: zone not found with journal
+The requested zone in IXFR was not found in the data source
+even though the xfrout daemon sucessfully found the SOA RR of the zone
+in the data source.  This can happen if the administrator removed the
+zone from the data source within the small duration between these
+operations, but it's more likely to be a bug or broken data source.
+Unless you know why this message was logged, and especially if it
+happens often, it's advisable to check whether the data source is
+valid for this zone.  The xfrout daemon considers it a possible,
+though unlikely, event, and returns a response with an RCODE of
+NOTAUTH.
+