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Showing posts from March, 2011

How to fix this ssh error from a Cisco switch: ssh_rsa_verify: RSA modulus too small: 512 < minimum 768 bits

Problemssh user@cisco_switch returns:
ssh_rsa_verify: RSA modulus too small: 512 < minimum 768 bits key_verify failed for server_host_key Solution The modulus of the ssh RSA key pair on the switch is too small. If you have access, generate a new key pair on the switch with a larger modulus.
ProcedureLogin with ssh protocol version 1 (ssh space dash one): ssh -1 user@cisco_switch(On the switch): enable(On the switch): Authenticate to "Privileged Exec Mode" mode on the switch.(On the switch): conf t(On the switch): crypto key generate rsa general-keys modulus 1024(On the switch): Press enter to accept that the current key pair for the switch will be replaced. You now should be able to log into the switch with ssh protocol version 2.