CKB:SFTP Configuration Error

Applies To

Applies to: Cryptshare Ai> Transfer Processing > Archiving > Secure File Transfer Connector

Remote Host OS Version: openSUSE Leap 16.0 (upgraded from 15.6)

Problem

If the remote host is a VM with OS version openSUSE Leap 16.0, the SFTP connection test fails.

The Cryptshare logs show:

net.schmizz.sshj.sftp.SFTPException: EOF while reading packet   at net.schmizz.sshj.sftp.SFTPEngine.init(SFTPEngine.java:103)

The error appears at: Transfer Processing → Archiving → Secure File Transfer Connector Configuration → Test Connection.

Cause

The SSH daemon (sshd) is configured to launch the SFTP subsystem via a binary path that no longer exists on openSUSE 16.0.

openSUSE 16.0 relocated the sftp-server binary as part of a filesystem reorganization:

openSUSE 15.6 (old path)	openSUSE 16.0 (new path)
/usr/lib/ssh/sftp-server	/usr/libexec/ssh/sftp-server

The default sshd_config shipped with openSUSE 16.0 still references the old path. When sshd cannot find the binary, it closes the SFTP channel immediately — before sending any response — causing the EOF error in Cryptshare server.

Verification

On the remote host, confirm which path sshd is currently using:

sshd -T | grep subsystem

Incorrect output (causes the error):

subsystem sftp /usr/lib/ssh/sftp-server

Correct output (expected after fix):

subsystem sftp /usr/libexec/ssh/sftp-server

Solution

Run the following commands on the remote host as root:

echo 'Subsystem sftp /usr/libexec/ssh/sftp-server' > /etc/ssh/sshd_config.d/99-sftp-fix.conf

systemctl restart sshd

This creates a drop-in configuration file that overrides the incorrect default path without modifying the base sshd_config, making it upgrade-safe.

Once complete, retry the connection test in Cryptshare server: Transfer Processing → Archiving → Secure File Transfer Connector Configuration → Test Connection.

Note:

Do not edit /etc/ssh/sshd_config directly. Drop-in files under /etc/ssh/sshd_config.d/ are the recommended approach on openSUSE 16.0 and are preserved across package updates.