Unable to SSH to SSP appliance after upgrading to ISG 2.5.x

Products

• SSP
• SSP-S210
• SSP-S210 PLATFORM
• SSP-S410
• SSP-S410 PLATFORM
• SSP-S620 PLATFORM

Issue/Introduction

After upgrading the SSP(ISG) appliance from 2.4.10.1 to the 2.5.x.x version unable to log in via SSH.

Getting "Remote side unexpectedly closed network connection" error.

Cause

The ECDSA SSH host key not generated after the upgrade. 

Resolution

Go to the SSP serial console and run the following commands:

> enable
Password: ********
# configure t
(config)# ssh-console
(config-ssh-console)# host-keys
(config-host-keys)# create key-type ecdsa key-curve nistp256

If "already exists" is returned, delete the existing key first using the commands below:

(config-host-keys)# delete key-type ecdsa
(config-host-keys)# create key-type ecdsa key-curve nistp256

This will be fixed in ISG 2.5.6.1 version.