In NSX 4.0.X/4.1.X releases, backup fails when using a user name that starts with “sftp”.

Products

• VMware NSX Networking

Issue/Introduction

• NSX Manager backups are failing intermittently after upgrade to 4.0/4.1 release
• The SFTP user name used for backup is a user name starting with “sftp” such as “sftpbackup” , “sftpuser” , etc.
• From NSX Manager syslog(/var/log/syslog.log), the following error messages are observed.
  
  YYYY-MM-DDTHH:MM:SS <hostname> NSX ##### - [nsx@#### comp="nsx-manager" subcomp="node-mgmt" username="root" level="ERROR" errorCode="NOD110"] Cluster backup file copy operation failed due to 404 Not Found#015#012Content-Type: application/json#015#012Content-Length: 333#015#012#015#012{"error_code": 36219, "error_message": "Specified uri '<backup_path>' not found.", "module_name": "node-services"}
YYYY-MM-DDTHH:MM:SS <hostname> NSX ##### SYSTEM [nsx@#### comp="nsx-manager" errorCode="MP29111" level="ERROR" subcomp="manager"] Cluster backup for NSX_UFO_BACKUP_RESTORE had error
YYYY-MM-DDTHH:MM:SS <hostname> NSX ##### - [nsx@#### comp="nsx-manager" errorCode="MP29111" level="ERROR" s2comp="backup-restore" subcomp="manager"] Cluster backup failed with ; BackupAsyncStatus [BackupStatus [status=URI_NOT_FOUND, statusDetail=Specified uri '<backup_path>' not found., remoteUri=sftp://<remote_backup_path>, errorCode=null, startTime=<unixtime>, endTime=<unixtime>]; responseBody=null].
YYYY-MM-DDTHH:MM:SS <hostname> NSX ##### - [nsx@#### comp="nsx-manager" subcomp="node-mgmt" username="root" level="ERROR" errorCode="NOD110"] REPEATS: 1 repeats in 6 sec: Cluster backup file copy operation failed due to 404 Not Found#015#012Content-Type: application/json#015#012Content-Length: 333#015#012Vmw-Task-Id: <uuid>#012#015#012{"error_code": 36219, "error_message": "Specified uri '<backup_path>' not found.", "module_name": "node-services"}

Environment

VMware NSX 4.0.X
VMware NSX 4.1.X

Cause

This issue happens due to following configuration at the end of sshd_config.
Customer has configured "ChrootDirectory /sftpfiles" for sftp user group.

------------
Match group sftp
ChrootDirectory /sftpfiles
#X11Forwarding no
#AllowTcpForwarding no
ForceCommand internal-sftp
------------

Resolution

This issue is resolved in VMware NSX 4.2.0

Workaround:
On the backup server side, prepare a user that does not start with “sftp” and specify it as the SFTP user name for backup.

Additional Information

If it is difficult to prepare new users on the backup server, the following KB can also help.
KB 324251 - NSX Manager backups are failing intermittently after upgrade to 4.0/4.1 release