SAP Connectivity fails with error failed: Connect from SAP gateway to RFC server failed

SYMPTOM

Connectivity test failed for config 'SAP_Config'. Application deployment will continue. 
Error was: com.sap.conn.jco.JCoException: (102) JCO_ERROR_COMMUNICATION: Initialization of destination 
a22fcabd-b376-4f0a-bcdb-b66cd249fb13 failed: Connect from SAP gateway to RFC server failed
Connection parameters: TYPE=A DEST=a22fcabd-b376-4f0a-bcdb-b66cd249fb13 ASHOST=X.X.X.X SYSNR=00 PCS=1

LOCATION    SAP-Gateway on host SAPECCDEV01 / sapgw00
ERROR       timeout during allocate
TIME        Wed Jun  9 13:23:45 2021
RELEASE     749
COMPONENT   SAP-Gateway
VERSION     2
RC          242
MODULE      /bas/749_REL/src/krn/si/gw/gwr3cpic.c
LINE        2211
DETAIL      no connect of TP sapdp00 from host X.X.X.X after 20 sec
COUNTER     3

com.mulesoft.connector.sap.internal.error.exception.UnableToReachDestinationException: 
com.sap.conn.jco.JCoException: (102) JCO_ERROR_COMMUNICATION: Initialization of destination 
a22fcabd-b376-4f0a-bcdb-b66cd249fb13 failed: Connect from SAP gateway to RFC server failed
Connection parameters: TYPE=A DEST=a22fcabd-b376-4f0a-bcdb-b66cd249fb13 ASHOST=X.X.X.X SYSNR=00 PCS=1

LOCATION    SAP-Gateway on host SAPECCDEV01 / sapgw00
ERROR       timeout during allocate
TIME        Wed Jun  9 13:23:45 2021
RELEASE     749
COMPONENT   SAP-Gateway
VERSION     2
RC          242
MODULE      /bas/749_REL/src/krn/si/gw/gwr3cpic.c
LINE        2211
DETAIL      no connect of TP sapdp00 from host X.X.X.X after 20 sec
COUNTER     3

	at com.mulesoft.connector.sap.internal.connection.JCoConnection.validate(JCoConnection.java:120)
	at com.mulesoft.connectors.commons.template.connection.provider.ConnectorConnectionProvider.validate
(ConnectorConnectionProvider.java:36)
	at com.mulesoft.connectors.commons.template.connection.provider.ConnectorConnectionProvider.validate
(ConnectorConnectionProvider.java:16)
	at org.mule.runtime.module.extension.internal.runtime.config.ClassLoaderConnectionProviderWrapper.validate
(ClassLoaderConnectionProviderWrapper.java:72)
	at org.mule.runtime.core.internal.connection.ReconnectableConnectionProviderWrapper.validate
(ReconnectableConnectionProviderWrapper.java:50)
	at org.mule.runtime.core.internal.connection.ErrorTypeHandlerConnectionProviderWrapper.validate
(ErrorTypeHandlerConnectionProviderWrapper.java:85)
	at org.mule.runtime.core.internal.connection.DefaultConnectionManager.doTestConnectivity
(DefaultConnectionManager.java:186)
	at org.mule.runtime.core.internal.connection.DefaultConnectionManager.lambda$testConnectivity$1
(DefaultConnectionManager.java:169)
	at org.mule.runtime.core.internal.connection.DefaultConnectionManager.doTestConnectivity
(DefaultConnectionManager.java:176)
	at org.mule.runtime.core.internal.connection.DefaultConnectionManager.testConnectivity
(DefaultConnectionManager.java:152)
	at org.mule.runtime.core.internal.connection.DelegateConnectionManagerAdapter$EagerConnectionManagerAdapter.
testConnectivity(DelegateConnectionManagerAdapter.java:176)
	at org.mule.runtime.core.internal.connection.DelegateConnectionManagerAdapter.testConnectivity
(DelegateConnectionManagerAdapter.java:98)
	at org.mule.runtime.module.extension.internal.runtime.config.LifecycleAwareConfigurationInstance$1.
doWork(LifecycleAwareConfigurationInstance.java:194)
	at org.mule.runtime.core.api.retry.policy.AbstractPolicyTemplate.execute(AbstractPolicyTemplate.java:62)
	at org.mule.runtime.core.internal.retry.async.RetryWorker.run(RetryWorker.java:56)
	at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
	at java.util.concurrent.FutureTask.run(FutureTask.java:266)
	at org.mule.service.scheduler.internal.AbstractRunnableFutureDecorator.doRun(AbstractRunnableFutureDecorator.java:111)
	at org.mule.service.scheduler.internal.RunnableFutureDecorator.run(RunnableFutureDecorator.java:54)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
	at java.lang.Thread.run(Thread.java:748)
Caused by: com.sap.conn.jco.JCoException: (102) JCO_ERROR_COMMUNICATION: 
Initialization of destination a22fcabd-b376-4f0a-bcdb-b66cd249fb13 failed: Connect from SAP gateway to RFC server failed
Connection parameters: TYPE=A DEST=a22fcabd-b376-4f0a-bcdb-b66cd249fb13 ASHOST=X.X.X.X SYSNR=00 PCS=1

LOCATION    SAP-Gateway on host SAPECCDEV01 / sapgw00
ERROR       timeout during allocate
TIME        Wed Jun  9 13:23:45 2021
RELEASE     749
COMPONENT   SAP-Gateway
VERSION     2
RC          242
MODULE      /bas/749_REL/src/krn/si/gw/gwr3cpic.c
LINE        2211
DETAIL      no connect of TP sapdp00 from host X.X.X.X after 20 sec
COUNTER     3

	at com.sap.conn.jco.rt.RfcDestination.initialize(RfcDestination.java:901)
	at com.sap.conn.jco.rt.RfcDestination.ping(RfcDestination.java:1295)
	at com.mulesoft.connector.sap.internal.connection.JCoConnection.validate(JCoConnection.java:115)
	... 21 more
Caused by: com.sap.conn.jco.JCoException: (102) JCO_ERROR_COMMUNICATION: Connect from SAP gateway to RFC server failed
Connection parameters: TYPE=A DEST=a22fcabd-b376-4f0a-bcdb-b66cd249fb13 ASHOST=X.X.X.X SYSNR=00 PCS=1

CAUSE

• The issue is in the internal SAP configuration, specifically to do with the connection between SAP Gateway and SAP RFC host. 
• This is not an issue in the MuleSoft configuration or on the MuleSoft side.

SOLUTION