Hi Riccardo,
„epoch 0, seqn 0“:
The errors occurs on the wakaama client side?
Are you using a Wakaama server? Or Leshan?
If your using Leshan Server and Wakaama client, this may be caused by the DTLS role exchange,
I’m not sure, if tinyDTLS is aware of that feature.
If you could provide a WireShark capture, this would help.
By the way, calling “dtls_renegotiate” may not work, it assumes a valid DTLS session.
See https://sourceforge.net/p/tinydtls/tickets/12/
Mit freundlichen Grüßen / Best regards
Achim Kraus
Bosch Software Innovations GmbH
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Von: wakaama-dev-bounces@xxxxxxxxxxx [mailto:wakaama-dev-bounces@xxxxxxxxxxx]
Im Auftrag von Riccardo Pozza
Gesendet: Montag, 16. Januar 2017 10:46
An: 'Wakaama developer discussions' <wakaama-dev@xxxxxxxxxxx>
Betreff: [wakaama-dev] DTLS handshake errors
Hi all,
I’ve upgraded recently to DTLS communication on my lwm2m client.
Sometimes I need to re-handshake with DTLS for re-registration and I rarely get errors, but I do get them during the handshake procedure.
Examples thereof:
è
Error DTLS handling message -552.
o
The message sequence number is too small, expected XXXX, got 0:
è
WARN, Wrong epoch, expected X, got 0
Sometimes I just see the initial ClientHello packet sent and no reply whatsoever.
The issue in this case is that the client blocks and never gets out unless rebooted, which I’d like to avoid.
What is the behaviour on the failed DTLS handshake?
Is it possible to render this non-blocking?
Thanks and Kind Regards,
Riccardo.