migration revision 816e576f77e2c46df3e3d97d65822aa8aded7c4b
ba287763fb250c9244e7a7afc1abff9387b94e43vboxsyncCopyright (C) 2000 Internet Software Consortium.
ba287763fb250c9244e7a7afc1abff9387b94e43vboxsyncSee COPYRIGHT in the source root or http://isc.org/copyright.html for terms.
ba287763fb250c9244e7a7afc1abff9387b94e43vboxsync BIND 8 to BIND 9 Migration Notes
ba287763fb250c9244e7a7afc1abff9387b94e43vboxsyncBIND 9 is designed to be mostly upwards compatible with BIND 8, but
ba287763fb250c9244e7a7afc1abff9387b94e43vboxsyncthere is still a number of caveats you should be aware of when
ba287763fb250c9244e7a7afc1abff9387b94e43vboxsyncupgrading an existing BIND 8 installation to use BIND 9.
ba287763fb250c9244e7a7afc1abff9387b94e43vboxsync1. Configuration File Compatibility
ba287763fb250c9244e7a7afc1abff9387b94e43vboxsync1.1. Unimplemented Options and Changed Defaults
ba287763fb250c9244e7a7afc1abff9387b94e43vboxsyncBIND 9.0.0 supports most, but not all but not of the named.conf
ba287763fb250c9244e7a7afc1abff9387b94e43vboxsyncoptions of BIND 8. Unimplemented options include those for selective
ba287763fb250c9244e7a7afc1abff9387b94e43vboxsync(per-domain) forwarding, sortlists, statistics, and process limits;
ba287763fb250c9244e7a7afc1abff9387b94e43vboxsyncfor a complete list, see doc/misc/options. We plan to implement most
ba287763fb250c9244e7a7afc1abff9387b94e43vboxsyncof these in in BIND 9.1.
ba287763fb250c9244e7a7afc1abff9387b94e43vboxsyncIf your named.conf file uses an unimplemented option, named will log a
ba287763fb250c9244e7a7afc1abff9387b94e43vboxsyncwarning message. A message is also logged about each option whose
ba287763fb250c9244e7a7afc1abff9387b94e43vboxsyncdefault has changed unless the option is set explicitly in named.conf.
ba287763fb250c9244e7a7afc1abff9387b94e43vboxsync1.2. Logging
ba287763fb250c9244e7a7afc1abff9387b94e43vboxsyncThe set of logging categories in BIND 9 is different from that
ba287763fb250c9244e7a7afc1abff9387b94e43vboxsyncin BIND 8. If you have customized your logging on a per-category
ba287763fb250c9244e7a7afc1abff9387b94e43vboxsyncbasis, you need to modify your logging statement to use the
ba287763fb250c9244e7a7afc1abff9387b94e43vboxsyncnew categories.
ba287763fb250c9244e7a7afc1abff9387b94e43vboxsyncAnother difference is that the "logging" statement only takes effect
ba287763fb250c9244e7a7afc1abff9387b94e43vboxsyncafter the entire named.conf file has been read. This means that when
ba287763fb250c9244e7a7afc1abff9387b94e43vboxsyncthe server starts up, any messages about errors in the configuration
ba287763fb250c9244e7a7afc1abff9387b94e43vboxsyncfile are always logged to the default destination (syslog) when the
ba287763fb250c9244e7a7afc1abff9387b94e43vboxsyncserver first starts up, regardless of the contents of the "logging"
ba287763fb250c9244e7a7afc1abff9387b94e43vboxsyncstatement. In BIND 8, the new logging configuration took effect
ba287763fb250c9244e7a7afc1abff9387b94e43vboxsyncimmediately after the "logging" statement was read.
ba287763fb250c9244e7a7afc1abff9387b94e43vboxsync2. Zone File Compatibility
ba287763fb250c9244e7a7afc1abff9387b94e43vboxsync2.1. Strict RFC1035 Interpretation of TTLs in Zone Files
e54b16ce4a8dbf2ade96b5d4c9e59ccea044c817vboxsyncBIND 8 allowed you to omit all TTLs from a zone file, and used the
e54b16ce4a8dbf2ade96b5d4c9e59ccea044c817vboxsyncvalue of the SOA MINTTL field as a default for missing TTL values.
ba287763fb250c9244e7a7afc1abff9387b94e43vboxsyncBIND 9 enforces strict compliance with the RFC1035 and RFC2308 TTL
ba287763fb250c9244e7a7afc1abff9387b94e43vboxsyncrules. The default TTL is the value specified with the $TTL
ba287763fb250c9244e7a7afc1abff9387b94e43vboxsyncdirective, or the previous explicit TTL if there is no $TTL directive.
ba287763fb250c9244e7a7afc1abff9387b94e43vboxsyncIf there is no $TTL directive and the first RR in the file does not
ba287763fb250c9244e7a7afc1abff9387b94e43vboxsynchave an explicit TTL field, the error message "no TTL specified" is
ba287763fb250c9244e7a7afc1abff9387b94e43vboxsynclogged and loading the zone file fails.
ba287763fb250c9244e7a7afc1abff9387b94e43vboxsyncTo avoid problems, use a $TTL directive in each zone file.
ba287763fb250c9244e7a7afc1abff9387b94e43vboxsync2.2. Periods in SOA Serial Numbers Deprecated
ba287763fb250c9244e7a7afc1abff9387b94e43vboxsyncSome versions of BIND allow SOA serial numbers with an embedded
ba287763fb250c9244e7a7afc1abff9387b94e43vboxsyncperiod, like "3.002", and convert them into integers in a rather
6dd8f5023a9ba7588212331db90059553136fe33vboxsyncunintuitive way. This feature is not supported by BIND 9; serial
ba287763fb250c9244e7a7afc1abff9387b94e43vboxsyncnumbers must be integers.
ba287763fb250c9244e7a7afc1abff9387b94e43vboxsync2.3. Handling of Unbalanced Quotes
ba287763fb250c9244e7a7afc1abff9387b94e43vboxsyncTXT records with unbalanced quotes, like 'host TXT "foo', were not
ba287763fb250c9244e7a7afc1abff9387b94e43vboxsynctreated as errors in some versions of BIND. If your zone files
ba287763fb250c9244e7a7afc1abff9387b94e43vboxsynccontain such records, you will get potentially confusing error
ba287763fb250c9244e7a7afc1abff9387b94e43vboxsyncmessages like "unexpected end of file" because BIND 9 will interpret
ba287763fb250c9244e7a7afc1abff9387b94e43vboxsynceverything up to the next quote character as a literal string.
ba287763fb250c9244e7a7afc1abff9387b94e43vboxsync3. Interoperability Impact of New Protocol Features
ba287763fb250c9244e7a7afc1abff9387b94e43vboxsyncBIND 9 uses EDNS0 (RFC2671) to advertise its receive buffer size. It
ba287763fb250c9244e7a7afc1abff9387b94e43vboxsyncalso sets the AD bit in queries to indicate that it wishes to receive
ba287763fb250c9244e7a7afc1abff9387b94e43vboxsyncDNSSEC responses (this usage of the AD bit is not yet standard, but
ba287763fb250c9244e7a7afc1abff9387b94e43vboxsynchopefully it will be soon).
ba287763fb250c9244e7a7afc1abff9387b94e43vboxsyncMost older servers that do not support EDNS0 and/or DNSSEC, including
ba287763fb250c9244e7a7afc1abff9387b94e43vboxsyncall known versions of BIND, will send a FORMERR or NOTIMP response to
ba287763fb250c9244e7a7afc1abff9387b94e43vboxsyncthese queries. When this happens, BIND 9 will automatically retry the
ba287763fb250c9244e7a7afc1abff9387b94e43vboxsyncquery without EDNS0 and AD.
ba287763fb250c9244e7a7afc1abff9387b94e43vboxsyncUnfortunately, there exists at least one non-BIND name server
ba287763fb250c9244e7a7afc1abff9387b94e43vboxsyncimplementation that silently ignores these queries instead of sending
ba287763fb250c9244e7a7afc1abff9387b94e43vboxsyncan error response. Resolving names in zones where all or most
ba287763fb250c9244e7a7afc1abff9387b94e43vboxsyncauthoritative servers use this server will be very slow or fail
ba287763fb250c9244e7a7afc1abff9387b94e43vboxsynccompletely. We have contacted the manufacturer of the name server in
ba287763fb250c9244e7a7afc1abff9387b94e43vboxsynccase and are trying to resolve the issue with them.
ba287763fb250c9244e7a7afc1abff9387b94e43vboxsync$Id: migration,v 1.5 2000/08/09 04:37:41 tale Exp $