Broken SSH connection
Any of the following types of error messages are logged, according to the type of session that is running (SSH, SCP, or SFTP):
ssh: read error Bad file number, session aborted I 01/01/90 00:06:11 00636 ssh: sftp session from ::ffff:10.0.12.35 W 01/01/90 00:06:26 00641 ssh: sftp read error Bad file number, session aborted I 01/01/90 00:09:54 00637 ssh: scp session from ::ffff:10.0.12.35 W 01/01/90 ssh: scp read error Bad file number, session aborted
The Bad file number is from the system error value and may differ depending on the cause of the failure. In the third example, the device file to read was closed as the device read was about to occur.
If an ssh connection is broken at the wrong moment (for instance, the link goes away or spanning tree brings down the link), a fatal exception occurs on the switch. If this happens, the switch gracefully exits the session and produces an Event Log message indicating the cause of failure.