migration revision d8417b5f3406f4ace0f3bdb228b05a7b701976d6
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark AndrewsCopyright (C) 2000 Internet Software Consortium.
1fdd2470b625a58b57d0b155e6caf8c4fc0afe8aAutomatic UpdaterSee COPYRIGHT in the source root or http://www.isc.org/copyright for terms.
4a14ce5ba00ab7bc55c99ffdcf59c7a4ab902721Automatic UpdaterBIND 8 to BIND 9 Migration Notes
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark AndrewsBIND 9 is designed to be mostly upwards compatible with BIND 8, but
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrewsthere is still a number of caveats you should be aware of when
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrewsupgrading an existing BIND 8 installation to use BIND 9.
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews1. Configuration File Compatibility
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews1.1. Unimplemented Options and Changed Defaults
f8e3e03cacd16ffb923a9603fca23a9e1a1fee07Automatic UpdaterBIND 9.0.0 supports most, but not all but not of the named.conf
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrewsoptions of BIND 8. Unimplemented options include those for selective
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews(per-domain) forwarding, sortlists, statistics, and process limits;
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrewsfor a complete list, see doc/misc/options. We plan to implement most
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrewsof these in in BIND 9.1.
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark AndrewsIf your named.conf file uses an unimplemented option, named will log a
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrewswarning message. A message is also logged about each option whose
2a31bd531072824ef252c18303859d6af7451b00Francis Dupontdefault has changed unless the option is set explicitly in named.conf.
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews2. Zone File Compatibility
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews2.1. Strict RFC1035 Interpretation of TTLs in Zone Files
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark AndrewsBIND 8 allowed you to omit all TTLs from a zone file, and used the
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrewsvalue of the SOA MINTTL field as a default for missing TTL values.
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark AndrewsBIND 9 enforces strict compliance with the RFC1035 and RFC2308 TTL
2cbb4ab75757fbb656997a82c14ca07db37d481aAutomatic Updaterrules. The default TTL is the value specified with the $TTL
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrewsdirective, or the previous explicit TTL if there is no $TTL directive.
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark AndrewsIf there is no $TTL directive and the first RR in the file does not
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrewshave an explicit TTL field, the error message "no TTL specified" is
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrewslogged and loading the zone file fails.
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark AndrewsTo avoid problems, use a $TTL directive in each zone file.
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrews2.2. Periods in SOA Serial Numbers Deprecated
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark AndrewsSome versions of BIND allow SOA serial numbers with an embedded
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrewsperiod, like "3.002", and convert them into integers in a rather
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrewsunintuitive way. This feature is not supported by BIND 9; serial
f8e3e03cacd16ffb923a9603fca23a9e1a1fee07Automatic Updaternumbers must be integers.
f8e3e03cacd16ffb923a9603fca23a9e1a1fee07Automatic Updater2.3. Handling of Unbalanced Quotes
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark AndrewsTXT records with unbalanced quotes, like 'host TXT "foo', were not
d71e2e0c61df16ff37c9934c371a4a60c08974f7Mark Andrewstreated as errors in some versions of BIND. If your zone files
0a7ed88633a680bb881868b75ded4d09a7bbbc50Automatic Updatercontain such records, you will get potentially confusing error
0a7ed88633a680bb881868b75ded4d09a7bbbc50Automatic Updatermessages like "unexpected end of file" because BIND 9 will interpret
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrewseverything up to the next quote character as a literal string.
ad671240d635376dd8681550eebee799d2e3d1fdAutomatic Updater3. Interoperability Impact of New Protocol Features
ad671240d635376dd8681550eebee799d2e3d1fdAutomatic UpdaterBIND 9 uses EDNS0 (RFC2671) to advertise its receive buffer size. It
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrewsalso sets the AD bit in queries to indicate that it wishes to receive
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark AndrewsDNSSEC responses (this usage of the AD bit is not yet standard, but
f8e3e03cacd16ffb923a9603fca23a9e1a1fee07Automatic Updaterhopefully it will be soon).
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark AndrewsMost older servers that do not support EDNS0 and/or DNSSEC, including
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrewsall known versions of BIND, will send a FORMERR or NOTIMP response to
5a4557e8de2951a2796676b5ec4b6a90caa5be14Mark Andrewsthese queries. When this happens, BIND 9 will automatically retry the
0a7ed88633a680bb881868b75ded4d09a7bbbc50Automatic Updaterquery without EDNS0 and AD.
0a7ed88633a680bb881868b75ded4d09a7bbbc50Automatic UpdaterUnfortunately, there exists at least one non-BIND name server
0a7ed88633a680bb881868b75ded4d09a7bbbc50Automatic Updaterimplementation that silently ignores these queries instead of sending
0a7ed88633a680bb881868b75ded4d09a7bbbc50Automatic Updateran error response. Resolving names in zones where all or most
0a7ed88633a680bb881868b75ded4d09a7bbbc50Automatic Updaterauthoritative servers use this server will be very slow or fail
0a7ed88633a680bb881868b75ded4d09a7bbbc50Automatic Updatercompletely. We have contacted the manufacturer of the name server in
0a7ed88633a680bb881868b75ded4d09a7bbbc50Automatic Updatercase and are trying to resolve the issue with them.
0a7ed88633a680bb881868b75ded4d09a7bbbc50Automatic Updater$Id: migration,v 1.2 2000/07/12 05:06:33 gson Exp $