ISC DHCP 4.1.0a1 is now available

Evan Hunt Evan_Hunt at
Sat Feb 9 01:32:11 UTC 2008

ISC DHCP 4.1.0a1 is now available for download.

This is FIRST ALPHA release of ISC DHCP 4.1.0, a feature release focused
on expanding support for DHCPv6.  A list of changes in this release has
been appended to this message.  For a full list of changes since any
historical version, please consult the RELNOTES file in the software
distribution, or on our website:

ISC DHCP 4.1.x will have several new DHCPv6 features that were not in
DHCP 4.0.x.  These will include:

- Support for the rapid-commit option on the client side

- Prefix Delegation support

- IA_TA address support

- A basic DHCPv6 relay agent, dhcrelay6

There are a number of DHCPv6 limitations and features missing in this
release, which will be addressed in the future:

- Only Solaris, Linux, FreeBSD, NetBSD, and OpenBSD are supported.

- Only a single address is supported per IA.

- DHCPv6 includes human-readable text in status code messages. These
  should be configurable, and probably localized via gettext() or the

- The "host-identifier" option is limited to a simple token.

- The client and server can only operate DHCPv4 or DHCPv6 at a time,
  not both.  To use both protocols simultaneously, two instances of the
  relevant daemon are required, one with the '-6' command line option.

For information on how to install, configure and run this software, as
well as how to find documentation and report bugs, please consult the
README file.

ISC DHCP uses standard GNU configure for installation. Please review the
output of "./configure --help" to see what options are available.

The system has only been tested on Linux, FreeBSD, and Solaris, and may not
work on other platforms. Please report any problems and suggested fixes to
<dhcp-users at>.

			Changes since 4.0.0 (new features)

- Added DHCPv6 rapid commit support.

- Added explicit parser support for zero-length DHCP options, such as
  rapid-commit, via format code 'Z'.

- It's now possible to update the "ends" field of a lease with OMAPI.
  This is useful if you want not only to release a lease, but also make
  it available for reuse right away.  Hat tip to Christof Chen.

- Fixed definition of the iaaddr hash functions to use the correct 
  functions when referencing and dereferencing memory.

- Some definitions not in phase with the IANA registry were updated.

- Allocated interface IDs are better controlled ('u' bit set to zero,
  reserved IDs avoided).

- Unicast options are taken into account only for RENEWs.

- NoAddrsAvail answers to SOLICITs are always ADVERTISEs even when a SOLICIT
  carries a rapid-commit option.

- Return in place of raise an impossible condition when one tries to release
  an empty active lease.

- Timer granularity is now 1/100s in the DHCPv6 client.

- The dhclient-script was updated to create a host route for the default
  gateway if the supplied subnet mask for an IPv4 address was a /32.  This
  allows the client to work in 'captive' network environments, where the
  operator does not want clients to crosstalk directly.

- MINUS tokens should be parseable again.

- Multiple (up to "delayed-ack x;" maximum) DHCPv4 packets are now queued and
  released in bursts after single fsync() events when the upper limit is
  reached or if the receiving sockets go dry.  The practical upshot is
  that fsync-coupled server performance is now multiplicitively increased.
  The default delayed ack limit is 28.  Thanks entirely to a patch from
  Christof Chen.

			Changes since 4.0.0 (bug fixes)

- DHCP now builds on AIX.

- Exit with warning when DHCPv6-specific statements are used in the
  config file but -6 is not specified.

- Fixed "--version" flag in dhcrelay

- The 'min-secs' configuration parameter's log message has been updated to
  be more helpful.

- The warning logged when an address range doesn't fit in the subnets
  they were declared has been updated to be more helpful and identify the
  typo in configuration that created the spanning addresses.

- A bug in failover pool rebalancing that caused POOLREQ message ping-pongs
  was repaired.

- A flaw in failover pool rebalancing that could cause POOLREQ messages to
  be sent outside of the min-balance/max-balance scheduled intervals has
  been repaired.

- A cosmetic bug during potential-conflict recovery that caused the peer's
  'conflict-done' state message to be logged as 'unknown-state' has been
  repaired.  It is now logged correctly.

- A bug was fixed where the 'giaddr' may be used to find the client's subnet
  rather than its own 'ciaddr'.

- A log message was introduced to clarify the situation where a failover
  'address' parameter (the server's local address) did not resolve to an
  IPv4 address.

- The minimum site code value was set to 224 in 3.1.0 to track RFC3942.  This
  broke a lot of legacy site local configurations.  The new code in place will
  track site local space minimum option codes and logs a warning to encourage
  updates and exploration of site local code migration problems.  Option
  codes less than 128 in site local spaces remain inaccessible.

- A possible relay agent option bug was repaired where random server
  initialization state may have been used to signal the relay agent
  information options sub-option code for the 'END' of the option space.

- Fixes to allow code to compile and run on Solaris 9.

- Fixes to allow code to compile on Mac OS X Leopard (10.5).

- When server is configured with options that it overrides, a warning is
  issued when the configuration file is read, rather than at the time the
  option is overridden. This was important, because the warning was given
  every time the option was overridden, which could create a lot of 
  unnecessary logging.

- Fixed a compilation problems on platforms that define a value for FDDI,
  which conflicts with a dhcp configuration syntax token by the same name.

- When a failover server suspects it has encountered a peer running a
  version 3.0.x failover server, a warning that the failover wire protocol
  is incompatible is printed.

- The failover server no longer issues a floating point error if it encounters
  a previously undefined option code.

Evan Hunt -- evan_hunt at
Internet Systems Consortium, Inc.
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