Subject: [dhcwg] [Technical Errata Reported] RFC5007 (3763)

From: RFC Errata System <[email-masked]>
Date: Wed, 23 Oct 2013 04:16:41 -0700 (PDT)

The following errata report has been submitted for RFC5007,
"DHCPv6 Leasequery".

--------------------------------------
You may review the report below and at:
http://www.rfc-editor.org/errata_search.php?rfc=5007&eid=3763

--------------------------------------
Type: Technical
Reported by: Darpan Malhotra <[email-masked]>

Section: GLOBAL

Original Text
-------------
4.3.3. Receipt of LEASEQUERY-REPLY

1.  If the server had bindings for the requested client, the message
    includes an OPTION_CLIENT_DATA option and the requestor extracts
    the client data from the LEASEQUERY-REPLY and updates its binding
    information database.  If the OPTION_CLIENT_DATA contains no
    OPTION_CLT_TIME, the requestor SHOULD silently discard the
    OPTION_CLIENT_DATA option.

4.3.4. Handling DHCPv6 Client Data from Multiple Sources

   The requestor SHOULD use the OPTION_CLT_TIME to resolve data
   conflicts originated from different servers, and SHOULD accept data
   with most recent OPTION_CLT_TIME.

Corrected Text
--------------
4.3.3. Receipt of LEASEQUERY-REPLY

1.  If the server had bindings for the requested client, the message
    includes an OPTION_CLIENT_DATA option and the requestor extracts
    the client data from the LEASEQUERY-REPLY and updates its binding
    information database.  

4.3.4. Handling DHCPv6 Client Data from Multiple Sources

   The requestor SHOULD use the OPTION_CLT_TIME to resolve data
   conflicts originated from different servers, and SHOULD accept data
   with most recent OPTION_CLT_TIME. If OPTION_CLT_TIME is not
   present in a response, then response from other servers having
   OPTION_CLT_TIME should be preferred.

Notes
-----
Consider the scenario of DHCPv6 Failover (as mentioned in RFC 7031), there will be cases where only one server (Main) would have communicated with the client. Bindings for the client will be present on both servers, but the partner server (Backup) will not have Client Last Transaction Time. When a requestor sends Leasequery to the backup server, the response should not contain OPTION_CLT_TIME.

Further, consider the following scenarios:
1. Requestor gets response for Leasequery from both servers (main and backup).
In this scenario, response having OPTION_CLT_TIME should be preferred by the requestor. This is the justification for adding the text in Section 4.3.4.

2. Requestor gets response for Leasequery from only from one server (as other server is down).
Consider main to be down. So, the requestor gets response only from Backup. The requestor should still accept this data. This is justification of removing the text from Section 4.3.3.

Instructions:
-------------
This errata is currently posted as "Reported". If necessary, please
use "Reply All" to discuss whether it should be verified or
rejected. When a decision is reached, the verifying party (IESG)
can log in to change the status and edit the report, if necessary. 

--------------------------------------
RFC5007 (draft-ietf-dhc-dhcpv6-leasequery-01)
--------------------------------------
Title               : DHCPv6 Leasequery
Publication Date    : September 2007
Author(s)           : J. Brzozowski, K. Kinnear, B. Volz, S. Zeng
Category            : PROPOSED STANDARD
Source              : Dynamic Host Configuration
Area                : Internet
Stream              : IETF
Verifying Party     : IESG