Synchronisation error: Timed out trying to read

[Former Member]

Dear Experts,

I am trying to synchronise data from SQL Anywhere to HANA db via Remote Data Sync Service. I am getting the error "Timed out trying to read". Kindly help with a solution. Following are the few log items before the error:

row_id,conn_id,result_time,result_type,parm_id,parm_message 131,198,2017-05-02 16:37:02.252,'DBSC_EVENTTYPE_PROGRESS_TEXT',0,Uploading... 132,198,2017-05-02 16:37:02.252,'DBSC_EVENTTYPE_INFO_MSG',0,Begin upload 132,198,2017-05-02 16:37:02.252,'DBSC_EVENTTYPE_INFO_MSG',1,1021 133,198,2017-05-02 16:37:02.252,'DBSC_EVENTTYPE_INFO_MSG',0,Negotiating communication protocol with MobiLink server. 133,198,2017-05-02 16:37:02.252,'DBSC_EVENTTYPE_INFO_MSG',1,1450 134,198,2017-05-02 16:41:03.739,'DBSC_EVENTTYPE_ERROR_MSG',0,Timed out trying to read 7 bytes. 134,198,2017-05-02 16:41:03.739,'DBSC_EVENTTYPE_ERROR_MSG',1,1285

[Former Member]

There is very little to go on here other than dbmlsync was waiting for the RDSync service (MobiLink) to respond but the response that came back was incomplete or was missing entirely.

That could be due to any number of different causes. The MobiLink server could have stopped, there was a broken link, a congested network or routing problem, or the MobiLink server was under an excessive load.

All we know (from the client side error) is we were expecting a 7 byte protocol unit/sequence and it never arrived.

You might find out more if you check this out from the server side but if this is rare and subsequent synchronizations work, then I would expect some transient networking issue hit you. If all syncs fail for a period of time after the first occurrence of this error then you could have a crashing or shutdown issue on the server side.

[Former Member]

This is my first attempt at Remote Data Synchronisation. Could there be any configuration mistake? Any parameter that I missed while creating the Synchronisation Profile?

[Former Member]

If the log shows that the rdsync server has received the synchronization request, you may want to confirm that you are using the same protocol on each end. By default rdsync server uses tcpip, but it can also listen for http requests (with and without encryption). The SYNCHRONIZATION SUBSCRIPTION defines the protocol on the SQL Anywhere side. On HANA, there is a configuration option (I would have to look it up, but it is in rdsyncserver.ini on the Configuration tab of the Administation pane) that sets the protocol. The trace file lists the protocol whenever the rdsync server is (re)started.

[Former Member]

The issue was the port number. How can I change the uploaded scripts since I uploaded the wrong schema.

[Former Member]

I have converted the comment suggesting the port number and log file to an answer. I don't really understand the "uploaded scripts" comment. Perhaps you could accept the answer on this question and open a new question?

[Former Member · Accepted solution]

Can you look at the RDSync Server log file and see if it received the synchronization request?

If you are using HANA Studio, you can do that by - connecting to HANA, - opening the Configuration and Monitoring > Administration page, - opening the trace file tab - looking for the most recent "rdsync" trace file - looking to see if there is any indication of a synchronization request.

If there is no synchronization request showing up in the log, you may have the wrong address in your synchronization subscription at SQL Anywhere. You should check that the host is correct, and that the port is 3NN28 (NOT 3NN27) where NN is the System ID.