2679285 - Unable to open connection to backend system - SAP Cloud Connector

The on-premise system mapped in the SCC (SAP Cloud Connector) cannot be reached.

This issue might generate malfunctions in the applications that connects to on-premise systems through SCC.

In the SCC traces "ljs_trace.log", located in the path "../<SCC_Install_Folder>/log", the following error is present:

+0000#ERROR#com.sap.core.connectivity.spi.processing.AbstractProtocolProcessor#tunnelclient-84-2# #Unable to open connection to backend system: java.nio.channels.UnresolvedAddressException
java.nio.channels.UnresolvedAddressException
at sun.nio.ch.Net.checkAddress(Net.java:164)
at sun.nio.ch.SocketChannelImpl.connect(SocketChannelImpl.java:704)
at io.netty.channel.socket.nio.NioSocketChannel.doConnect(NioSocketChannel.java:209
............

Or

+0000#ERROR#com.sap.core.connectivity.spi.processing.AbstractProtocolProcessor#tunnel-client-86-1#0xac546f25#Unable to open connection to backend system: <internal_hostname>
java.net.UnknownHostException: <internal_hostname>
    at java.net.InetAddress.getAllByName0(InetAddress.java:1335)
    at java.net.InetAddress.getAllByName(InetAddress.java:1247)
    at java.net.InetAddress.getAllByName(InetAddress.java:1175)
    at java.net.InetAddress.getByName(InetAddress.java:1125)
    at io.netty.util.internal.SocketUtils$8.run(SocketUtils.java:156)
    at io.netty.util.internal.SocketUtils$8.run(SocketUtils.java:153)
    at java.security.AccessController.doPrivileged(Native Method)
    at io.netty.util.internal.SocketUtils.addressByName(SocketUtils.java:153)
...........

SAP Cloud Connector

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