Troubleshooting JBoss Server Migration Tool in JBoss EAP

Issue

jboss-server-migration.sh failing to migrate with this error:

ERROR [logger] Migration failed: org.jboss.migration.core.ServerMigrationFailureException: org.jboss.migration.wfly10.config.management.ManagementOperationException: org.wildfly.core.embedded.EmbeddedProcessStartException: WFLYEMB0021: Cannot start embedded process
    at org.jboss.migration.cli@1.10.0.Final-redhat-00023//org.jboss.migration.core.task.TaskExecutionImpl.run(TaskExecutionImpl.java:174)
        ...
Caused by: org.jboss.migration.wfly10.config.management.ManagementOperationException: org.wildfly.core.embedded.EmbeddedProcessStartException: WFLYEMB0021: Cannot start embedded process
    at org.jboss.migration.cli@1.10.0.Final-redhat-00023//org.jboss.migration.wfly10.config.management.impl.EmbeddedStandaloneServerConfiguration.startConfiguration(EmbeddedStandaloneServerConfiguration.java:91)
        ...
Caused by: org.wildfly.core.embedded.EmbeddedProcessStartException: WFLYEMB0021: Cannot start embedded process
    at org.wildfly.embedded@15.0.22.Final-redhat-00001//org.wildfly.core.embedded.EmbeddedStandaloneServerFactory$StandaloneServerImpl.start(EmbeddedStandaloneServerFactory.java:324)
        ...
Caused by: java.util.concurrent.ExecutionException: JBTHR00005: Operation failed
    at org.jboss.threads@2.4.0.Final-redhat-00001//org.jboss.threads.AsyncFutureTask.get(AsyncFutureTask.java:253)
        ...
Caused by: java.lang.Exception: WFLYSRV0056: Server boot has failed in an unrecoverable manner; exiting. See previous messages for details.
    at org.jboss.as.server@15.0.22.Final-redhat-00001//org.jboss.as.server.BootstrapListener.bootFailure(BootstrapListener.java:87)
...