Filter
Top Products
C-16
Troubleshooting
Unusual Network Activity
SSH-Related Problems
Switch access refused to a client. Even though you have placed the cli-
ent’s public key in a text file and copied the file (using the copy tftp pub-key-
file command) into the switch, the switch refuses to allow the client to have
access. If the source SSH client is an SSHv2 application, the public key may
be in the PEM format, which the switch (SSHv1) does not interpret. Check the
SSH client application for a utility that can convert the PEM-formatted key
into an ASCII-formatted key.
Executing ip ssh does not enable SSH on the switch. The switch does
not have a host key. Verify by executing show ip host-public-key. If you see
the message
ssh cannot be enabled until a host key is configured
(use 'crypto' command).
then you need to generate an SSH key pair for the switch. To do so, execute
crypto key generate. (Refer to “Generating the Switch’s Public and Private Key
Pair” in the Access Security Guide for your switch.)
Switch does not detect a client’s public key that does appear in the
switch’s public key file (show ip client-public-key). The client’s public key
entry in the public key file may be preceded by another entry that does not
terminate with a new line (CR). In this case, the switch interprets the next
sequential key entry as simply a comment attached to the preceding key entry.
Where a public key file has more than one entry, ensure that all entries
terminate with a new line (CR). While this is optional for the last entry in the
file, not adding a new line to the last entry creates an error potential if you
either add another key to the file at a later time or change the order of the keys
in the file.
An attempt to copy a client public-key file into the switch has failed
and the switch lists one of the following messages:
Download failed: overlength key in key file.
Download failed: too many keys in key file.
Download failed: one or more keys is not a valid RSA
public key.