Setup WSO2 Enterprise Integrator VFS connection towards Windows SFTP server - windows

Question

Running WSO2 Enterprise Integrator 6.5.0. on RHEL 7. We are in the proces of building flows to read files from an sftp server. But setting up the sftp connection towards a Windows SFTP server fails. We can access this Windows SFTP server correctly with Windows clients like FileZilla/WinSCP.
With netstat we see a connection is build towards the Windows SFTP server but the flow isn't moving - no files are being read. On the point of stopping the server the error as shown below is printed in the wso2carbon.log.
When setting up the connection towards a Linux sftp server ( Plain RHEL 7 box with SSHD ) we don't face any issues. We have the matching private key place under .ssh/id_rsa in the home dir of the user running WSO2 EI.
Searching for the error message ( see snippet below ) we should get it resolved by adding the transport.vfs.AvoidPermissionCheck=true parameter to the VFS URL but unfortunately this doesn't solve our issue.
This is the VFS URL we are using.
sftp://SFTPUSER#SERVER.ACMECORP.ORG/inputdir?transport.vfs.AvoidPermissionCheck=true;vfs.passive=true
Is this a configuration that should work and are we missing a configuration option? Or is this a bug in the WSO2 software?
These URL's mention the issue we are facing.
VFS2 Error cannot delete file and could not get the groups id of the current user (error code: -1)
https://issues.apache.org/jira/browse/VFS-617
https://github.com/wso2/product-ei/issues/3725
[2019-12-06 13:48:59,724] [-1] [] [vfs-Worker-2] ERROR {org.apache.synapse.transport.vfs.VFSTransportListener} - Error checking for existence and readability : sftp://SFTPUSER#SERVER.ACMECORP.ORG/inputdir?transport.vfs.AvoidPermissionCheck=true;vfs.passive=true
org.apache.commons.vfs2.FileSystemException: Could not determine if file "sftp://SFTPUSER#SERVER.ACMECORP.ORG/inputdir?transport.vfs.AvoidPermissionCheck=true;vfs.passive=true" is readable.
at org.apache.commons.vfs2.provider.AbstractFileObject.isReadable(AbstractFileObject.java:1494)
at org.apache.synapse.transport.vfs.VFSTransportListener.scanFileOrDirectory(VFSTransportListener.java:295)
at org.apache.synapse.transport.vfs.VFSTransportListener.poll(VFSTransportListener.java:188)
at org.apache.synapse.transport.vfs.VFSTransportListener.poll(VFSTransportListener.java:134)
at org.apache.axis2.transport.base.AbstractPollingTransportListener$1$1.run(AbstractPollingTransportListener.java:67)
at org.apache.axis2.transport.base.threads.NativeWorkerPool$1.run(NativeWorkerPool.java:172)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
at java.lang.Thread.run(Thread.java:748)
Caused by: com.jcraft.jsch.JSchException: Could not get the groups id of the current user (error code: -1)
at org.apache.commons.vfs2.provider.sftp.SftpFileSystem.getGroupsIds(SftpFileSystem.java:219)
at org.apache.commons.vfs2.provider.sftp.SftpFileObject.getPermissions(SftpFileObject.java:250)
at org.apache.commons.vfs2.provider.sftp.SftpFileObject.doIsReadable(SftpFileObject.java:264)
at org.apache.commons.vfs2.provider.AbstractFileObject.isReadable(AbstractFileObject.java:1492)
... 8 more
UPDATE
Using the same URL but then setting up the WSO2 flow to write a file towards the SFTP server works.

Answer 1

Got this resolved with support from WSO2.
The correct VFS url to use is.
sftp://SFTPUSER#SERVER.ACMECORP.ORG/inputdir?transport.vfs.AvoidPermissionCheck=true&vfs.passive=true So a '&' seperator instead of a ';'.
The documentation of WSO2 just is very fuzzy about the correct syntax to use.
They give different examples across their documentation.
https://docs.wso2.com/display/EI650/VFS+Transport
https://docs.wso2.com/display/EI650/File+Inbound+Protocol
https://docs.wso2.com/display/EI650/Configuring+File+Inbound+Protocol+for+FTP%2C+SFTP+and+FILE+Connections