When you get your brand new Cisco ASR1000 series router, Stateful Switchover (SSO) is disabled by default:
Router# show redundancy states
my state = 13 -ACTIVE
peer state = 1 -DISABLED
Mode = Simplex
Unit ID = 6
Redundancy Mode (Operational) = Non-redundant
Redundancy Mode (Configured) = Non-redundant
Redundancy State = Non Redundant
Enable SSO …