Add SFTP TSG

Author: Clare-Zheng82

articles/data-factory/connector-troubleshoot-ftp-sftp-http.md

@@ -6,7 +6,7 @@ author: jianleishen
 ms.service: data-factory
 ms.subservice: data-movement
 ms.topic: troubleshooting
-ms.date: 10/01/2021
+ms.date: 03/11/2022
 ms.author: jianleishen
 ms.custom: has-adal-ref, synapse
 ---
@@ -172,6 +172,12 @@ This article provides suggestions to troubleshoot common problems with the FTP,
     1. On the ADF portal, hover on the SFTP linked service, and open its payload by selecting the code button.
     1. Add `"allowKeyboardInteractiveAuth": true` in the "typeProperties" section.
 
+### Unable to connect to SFTP due to key exchange algorithms provided by SFTP are not supported in ADF
+
+- **Symptoms**: You are unable to connect to SFTP via ADF.
+
+- **Cause**: The key exchange algorithms provided by the SFTP vendor are not supported in ADF. The key exchange algorithms supported by ADF are `diffie-hellman-group-exchange-sha256 [Redacted] diffie-hellman-group14-sha1`, while the key exchange algorithms in the SFTP vendor's list are `curve25519-sha256 ecdh-sha2-nistp256 ecdh-sha2-nistp384 ecdh-sha2-nistp521 diffie-hellman-group14-sha256 diffie-hellman-group15-sha512 diffie-hellman-group16-sha512 diffie-hellman-group17-sha512 diffie-hellman-group18-sha512`. 
+
 ## HTTP
 
 ### Error code: HttpFileFailedToRead