Re: CE 5.0 DHCP problems with short lease times

Coming back to this, I have been looking at the code .. but in testing,
discovered another oddity. If DHCP responses come slowly, WinCE seems to
ignore them in some cases.

For example, if a DHCPNAK response comes ~1 or more seconds after a
DHCPREQUEST, the NAK is completely ignored. On the other hand, if I decrease
the delay to just 0.9 seconds, then the NAK is handled and the net is taken
down, followed by a DISCOVER, etc.. to bring the net back up.

With other responses (i.e. DHCPOFFER, DHCPACK), it seems to be OK at
handling them even if they are slow to come back (but this may be because
WinCE sends multiple DISCOVERs and REQUESTs when in the state in which the
net is down) -- however in the renewing state, it only sends one REQUEST (as
expected), but then ignores a NAK if it receives it 1 second or more beyond
the time the REQUEST was sent.

Windows XP still handles the NAK if it receives it and restarts
configuration of the network. Even at ~3, 4, or 5 seconds.

Any idea on where this probable 1 second timer is, or if I can extend it
somehow?

Thanks,
D

"Tom Gensel (eMVP)" wrote:

It looks as if something is definitely rounding the T1 time, but the
DHCP client just does a simple divide by two on the lease time ( >>
1). The answer may lie in the implementation of the event timers used
to schedule the renewals. If you have the source look also in
\PRIVATE\WINCEOS\COMM\cxport directory to see the code used by the
DHCP client for scheduling. I never taken the time to study that area
of the source before.

Tom

On Wed, 30 Jul 2008 11:20:50 -0700, "Paul G. Tobey [eMVP]" <p space
tobey no spam AT no instrument no spam DOT com> wrote:

Do you have the source installed? It seems to me that the DHCP code is
found in the PRIVATE branch of the folder structure, if you do. Maybe
they're rounding to the nearest minute ;-)

Paul T.


.

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