Hi Arcady,
I think we would need to take a closer look at the environment and log file from dbmlsync, but I can see that dbmlsync will also note a 'Protocol Error' as a MobiLink communication error code - see: DocCommentXchange.
As mentioned previously, a 'Protocol Error' communication error still indicates that the issue should be with the MobiLink protocol commands themselves and we would expect that some connectivity has happened. Not finding the server at all should result in:
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I. 2015-02-19 14:19:40. Connecting to MobiLink server at 'host=missinghost' using 'TCPIP'
E. 2015-02-19 14:19:46. The host name 'missinghost' could not be found. The system-specific error code is 11001 (hex 00002af9).
E. 2015-02-19 14:19:46. Unable to connect to MobiLink server.
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We know that some HTTP proxies will buffer HTTP requests before forwarding them on, so a misconfigured (buffering) proxy could also result in protocol errors if it is not flushing the HTTP requests immediately.
Regards,
Jeff Albion
SAP Active Global Support
