unreliable DDNS updates by W2K clients

[Linsenbardt, Duane L.]

Hello:
We are experiencing intermittent DDNS registrations with Windows 2000,
Service Pack 1, clients to BIND V8 running under Solaris V2.6.  Below are
snippets from a failing and a successful trace.  Note difference between DNS
response packet 55 in first snippet and 60 in the second.  Any assistance
would be appreciated.

-Duane

Failing scenario:
50 DNS 0x7:Std Qry for d81000-41.ssd.jhuapl.edu. of type SOA on class INET
addr.
51 DNS 0x7:Std Qry Resp. Auth. NS is ssd.jhuapl.edu. of type SOA on class
INET addr. : Name does not exist
52 DNS 0x8:Std Qry for dallas.jhuapl.edu. of type Host Addr on class INET
addr.        
53 DNS 0x8:Std Qry Resp. Auth. NS is dallas.jhuapl.edu. of type Host Addr on
class INET addr.
54 DNS 0x9:Dyn Upd PRE records to d81000-41.ssd.jhuapl.edu. of type
Canonical name
55 DNS 0x9:Dyn Upd Resp.

Successful scenario:
55 DNS 0x7:Std Qry for d81000-41.ssd.jhuapl.edu. of type SOA on class INET
addr.
56 DNS 0x7:Std Qry Resp. Auth. NS is ssd.jhuapl.edu. of type SOA on class
INET addr. : Name does not exist
57 DNS 0x8:Std Qry for dallas.jhuapl.edu. of type Host Addr on class INET
addr. 
58 DNS 0x8:Std Qry Resp. Auth. NS is dallas.jhuapl.edu. of type Host Addr on
class INET addr.
59 DNS 0x9:Dyn Upd PRE records to d81000-41.ssd.jhuapl.edu. of type
Canonical name
60 DNS 0x9:Dyn Upd Resp. : RR set that ought to exist, does not exist
61 DNS 0xA:Std Qry for d81000-41.ssd.jhuapl.edu. of type SOA on class INET
addr.
62 DNS 0xA:Std Qry Resp. Auth. NS is ssd.jhuapl.edu. of type SOA on class
INET addr. : Name does not exist
63 DNS 0xB:Std Qry for dallas.jhuapl.edu. of type Host Addr on class INET
addr.
64 DNS 0xB:Std Qry Resp. Auth. NS is dallas.jhuapl.edu. of type Host Addr on
class INET addr.
65 DNS 0xC:Dyn Upd PRE/UPD records to d81000-41.ssd.jhuapl.edu. of type
Canonical name
66 DNS 0xC:Dyn Upd Resp.