Subject: what's new in draft-ietf-dhc-failover-08.txt

From: Kim Kinnear <[email-masked]>
Date: Wed, 22 Nov 2000 11:31:22 -0500

I just submitted the -08 version of the failover draft:
draft-ietf-dhc-failover-08.txt.

It will no doubt be available on the IETF web site in a few days.
I will be more than happy to send a copy of it to anyone who
simply can't wait for it to wend its way through to the IETF
site.

The point of this email is to give anyone interested the
list of what changed in this revision, which I've listed below.

Cheers -- Kim

---------------------------------------------------------

Changes to DHCP failover draft in November 2000 revision:

1.  Removed BACKUP-RESERVED IP address state, and added IP-flags
option to contain a RESERVED and a BOOTP flag.  Modified text to
remove BACKUP-RESERVED state and add words for RESERVED and BOOTP
flag.

2.  Added a new section 5.4, IP address allocations between
servers, which explains in considerably more detail the reasoning
behind the IP address allocations process between server as well
as the specific techniques that should be used by the primary and
secondary servers in dealing with available addresses.  Included
directions to consider loadbalancing and the most recent client
MAC address when making decisions as to which server gets which
addresses.

3.  Added section 5.13, What is sent in response to an UPDREQ or
UPDREQALL message, to better explain the issues surrounding
change of failover partner and how to handle total update of
failover partner.

4.  Fixed Table 7.9.1 to have two columns, one for accept and one
for reject to make it agree with the text and to respond to Ted's
comments.

5.  Fixed startup section to talk about states than partner down.
In particular, for other connected states (other than NORMAL,
which is mentioned).  Corrected RECOVER state to show it as
either communications OK and no OK in figure 9.2-1.  Also
renumbered the steps to get them in order.

6.  Added the state RESOLUTION-INTERRUPTED to the table in 9.4.3.

7.  Added information on what to do if in RECOVER state and
communications is interrupted.

8.  In section 9.5.2, made the time listed as "the current time"
be "the time the server came up".  These could be different in
this case because there is an UPDREQALL->UPDDONE sequence between
when the server came up and the current time.

9.  Added information to the NORMAL state in the text and in the
transition diagram on how to handle the SHUTDOWN and PAUSED
transitions that might be received from another server.

10.  Ted said that you could make transitions into SHUTDOWN state
from lots of other states, but that wasn't called out anywhere.
When looking into this, Kim realized that you don't really
transition into SHUTDOWN or PAUSED state, but rather tell your
partner that (but leave your own current state the same).  Added
some words to the intro of the figure 9.2-1 describing this.

11.  Clarified the hash-bucket-assignment option as being
directed to the secondary server.

12.  Added a new state, CONFLICT-DONE, to handle differing degree
of responsiveness as primary transitions out of
POTENTIAL-CONFLICT state.  This is analogous to the
RECOVER/RECOVER-DONE synchronization point (which is needed for a
different reason).  Modified the state transition diagram as
well as added a new section describing the state.

13.  Added new port 847 in place of port TBD throughout the
draft.

14.  Tied reject reasons to sections of the draft where they
appear, and (in general), included specifics of numbers and
message text in the text of the draft.

-------------------

Pg.  91: Ted said that he had a situation where two servers would
go into COMMUNICATIONS-INTERRUPTED state and NORMAL state and
back again.  He felt that it probably wasn't the draft's fault,
but it still happened and he finally fixed it.

Kim said that he would see if the draft could be tightened up in
this area.  He didn't find anything to change.