I seen this with other versions of 12.1X44-D35 to 12.1X46-D30 but out of 100 firewalls only about 4 experienced this issue.
Issue:
SRX100H running 12.1X44-D40 was upgraded to 12.1X46-D72 via Junos SPACE. The upgrade reported as failed but the customer isn't complaining about access and I can ping the inside interface. When I attempt to ssh to the firewall I get: "ssh_exchange_identification: Connection closed by remote host".
I asked google but he didn't answer me. I only found references to upgraded to 17 and needing to enable a ssh command to correct it but that's not my problem.
I have about 130 more srx100H's that I need to upgrade to the recommended code version and I can't move forward if I'm going to lose management access.
Does anyone know how to prevent this from occuring?