Re: CE 5.0 DHCP problems with short lease times

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I've done some more testing and confirmed that in a Renewal state, the DHCP
client will not update its lease time and lease expiry time if the ACK
received in response to a REQUEST is not received within 1 second. Same goes
for the NAK that I previously mentioned.

So it seems as though the CE 5.0 DHCP client is ignoring any responses after
1 second has expired since a REQUEST sent.

Windows XP doesn't have this problem.

Hmm... I wonder if this is intended behaviour or not.

Thanks,
D

"Paul G. Tobey [eMVP]" wrote:

Again, you'd have to look at the code (PRIVATE). I doubt that you can
extend it without editing the code and you probably don't have enough of the
code to actually rebuild the DHCP DLL. However, if you find an error, you
might be able to get Microsoft to release a fix...

Paul T.

"dataiv" <dataiv@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote in message
news:FAA2CCF5-53A4-4FD0-9538-034625490431@xxxxxxxxxxxxxxxx
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
.

Relevant Pages

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