What do these errors really mean?

[marcelstoer]

I have difficulties assessing the severity of errors reported by the library. The HTTPS exchange does succeed, no problem, but...

What is the system trying to tell me? Should I be worried? What should be done differently?

23:18:11.190 > Received 255847 bytes
23:18:12.157 > (EthernetSSLClient)(SSL_ERROR)(m_update_engine): Error writing to m_client
23:18:12.163 > (EthernetSSLClient)(SSL_ERROR)(m_update_engine): 0
23:18:12.168 > (EthernetSSLClient)(SSL_WARN)(connected): Socket was dropped unexpectedly (this can be an alternative to closing the connection)
23:18:12.180 > (EthernetSSLClient)(SSL_ERROR)(connected): Not connected because write error is set
23:18:12.186 > (EthernetSSLClient)(SSL_ERROR)(m_print_ssl_error): SSL_CLIENT_WRITE_FAIL
23:18:12.190 > (EthernetSSLClient)(SSL_ERROR)(available): SSL engine failed to update.
23:18:12.196 > (EthernetSSLClient)(SSL_ERROR)(connected): Not connected because write error is set
23:18:12.201 > (EthernetSSLClient)(SSL_ERROR)(m_print_ssl_error): SSL_CLIENT_WRITE_FAIL
23:18:12.212 > Total byte count: 268316
23:18:12.212 > 
23:18:12.212 > Disconnecting. Status code: 4
23:18:12.218 > (EthernetSSLClient)(SSL_ERROR)(connected): Not connected because write error is set
23:18:12.223 > (EthernetSSLClient)(SSL_ERROR)(m_print_ssl_error): SSL_CLIENT_WRITE_FAIL
23:18:12.229 > Received 268316 bytes in 21.8135 s, rate = 12.30 kbytes/second

[khoih-prog]

23:18:12.157 > (EthernetSSLClient)(SSL_ERROR)(m_update_engine): Error writing to m_client
23:18:12.163 > (EthernetSSLClient)(SSL_ERROR)(m_update_engine): 0

From

EthernetWebServer_SSL/src/SSLClient/SSLClient_Impl.h

Lines 660 to 667 in 15a1d4c

	// if the arduino client encountered an error
	if (m_client.getWriteError() || !m_client.connected())
	{
	m_error("Error writing to m_client", func_name);
	m_error(m_client.getWriteError(), func_name);
	setWriteError(SSL_CLIENT_WRTIE_ERROR);
	}

Nothing to worry because !m_client.connected() as m_client.getWriteError() == 0

We'd tried to write while client is not connected

2. The followings are the results of 1.,

23:18:12.168 > (EthernetSSLClient)(SSL_WARN)(connected): Socket was dropped unexpectedly (this can be an alternative to closing the connection)
23:18:12.180 > (EthernetSSLClient)(SSL_ERROR)(connected): Not connected because write error is set
23:18:12.186 > (EthernetSSLClient)(SSL_ERROR)(m_print_ssl_error): SSL_CLIENT_WRITE_FAIL
23:18:12.190 > (EthernetSSLClient)(SSL_ERROR)(available): SSL engine failed to update.
23:18:12.196 > (EthernetSSLClient)(SSL_ERROR)(connected): Not connected because write error is set
23:18:12.201 > (EthernetSSLClient)(SSL_ERROR)(m_print_ssl_error): SSL_CLIENT_WRITE_FAIL
23:18:12.212 > Total byte count: 268316
23:18:12.212 > 
23:18:12.212 > Disconnecting. Status code: 4
23:18:12.218 > (EthernetSSLClient)(SSL_ERROR)(connected): Not connected because write error is set
23:18:12.223 > (EthernetSSLClient)(SSL_ERROR)(m_print_ssl_error): SSL_CLIENT_WRITE_FAIL

We'd tried to write while client is not connected

So check the code to see where, then fix if any issue. Also check to be sure client is connected before writing something.

Possibly a bug somewhere in the library ??? or your code ??? I don't know

I don't think this can create any big issue because we'll rewrite if some data / packets are lost. But it's still better to find out the root cause.

As you're familiar with SSLClient library, you can also try to duplicate and make a Minimal, Reproducible Example and post an issue/ discussion there.

[marcelstoer]

After some more digging it appears to be this bug here: OPEnSLab-OSU/SSLClient#43