Bizarre limit alert.

Conrad Minshall conrad at
Tue Feb 25 08:48:53 GMT 2003

I don't use ECHO yet, but I debugged much the same symptom on a 
WRITE.  I recall the conclusion was that maximum buffer size includes 
the NB wrapper, but I'd have to revisit the code changed to be sure. 
NT dropping the WRITE had bad consequences of course :(

>I've been testing the SMB Echo message and found a very odd thing.
>If I send an echo request message to NT4 SP6 with a payload of 4323 bytes
>NT4 responds just fine.  If the payload is 4324 bytes NT4 does not reply.
>Of interest, the payload of 4323 bytes generates one ECHO Request and two
>continuation messages on the (Ethernet) wire.  The ECHO Request and first
>continuation message are 1514 bytes in (total) length.  The last
>continuation message is 1498 bytes...16 bytes less than 1514.  Hmmm...
>I like weird stuff like this.
>Chris -)-----
>PS.  W2K doesn't have the same problem.  I can send an ECHO Request with
>      a payload as big as 16611 bytes.  Curiously, at 16612 bytes and above
>      W2K will reset the connection.  "Connection reset by peer".
>Samba Team --     -)-----   Christopher R. Hertel
>jCIFS Team --   -)-----   ubiqx development, uninq.
>ubiqx Team --     -)-----   crh at
>OnLineBook --    -)-----   crh at

Conrad Minshall h:408-446-2323 rad at / w:408-974-2749 conrad at

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