The behavior seems as expected - the SCP code sends this warning/error via its STDERR stream and then aborts the channel.
The problem seems obvious and not related to SSHD - the target device/partition where the files are copied into has run out of space. There is nothing that SSH/SCP or anyone can do since this is not something that is signaled or handled in any way as part of the standard protocol. I believe the behavior you are seeing shows the quality of the SSH code - it has failed, but it leaves enough "traces" in the log in order to provide some useful information as to the problem and thus help you fix it/ >> I'm trying to upload files using mina sshd SCP connection. After uploading some of the files scp starts failing with the below exception, but If I see the logs from mina sshd it showing me a WARNING as "WARN (ScpHelper.java:820) - readAck(ScpHelper[ClientSessionImpl[david@/192.168.33.23:22]])[EOF=false] - Received warning: scp: /tmp/testcase4//36.bdf: No space left on device" But the exception I'm getting is different org.apache.sshd.common.channel.exception.SshChannelClosedException: write(ChannelOutputStream[ChannelExec[id=196, recipient=1]-ClientSessionImpl[david@/192.168.33.23:22]] SSH_MSG_CHANNEL_DATA) len=8192 - channel already closed at org.apache.sshd.common.channel.ChannelOutputStream.write(ChannelOutputStream.java:110) at org.apache.sshd.common.util.io.IoUtils.copy(IoUtils.java:128)Channel initialized: 198