+---mgr_keys
| authorized_keys
\---oper_keys
| authorized_keys
\---core
| port_1-24.cor core-dump for ports 1-24 (
stackable switches only
)
| port_25-48.cor core-dump for ports 25-48 (
stackable switches only
)
Once you have configured your switch for secure file transfers with SCP and SFTP, files can be copied to or from
the switch in a secure (encrypted) environment and TFTP is no longer necessary.
Troubleshooting SSH, SFTP, and SCP operations
Cause
You can verify secure file transfer operations by checking the switch's event log, or by viewing the error messages
sent by the switch that most SCP and SFTP clients print out on their console.
NOTE:
Messages that are sent by the switch to the client depend on the client software in use to
display them on the user console.
Broken SSH connection
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. The following three examples show the error
messages that may appear in the log, depending on 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
NOTE:
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.
Attempt to start a session during a flash write
If you attempt to start an SCP (or SFTP) session while a flash write is in progress, the switch does not allow the
SCP or SFTP session to start. Depending on the client software in use, the following error message may appear
on the client console:
Received disconnect from 10.0.12.31: 2: Flash access in
progress
lost connection
Failure to exit from a previous session
This next Example: shows the error message that may appear on the client console if a new SCP (or SFTP)
session is started from a client before the previous client session has been closed (the switch requires
approximately ten seconds to timeout the previous session):
Chapter 11 File Transfers
353
