For a ISR4451 there is a SM-D-ES3G-48-P Module, is this module hotplugable or should I power down the ISR for install the SM Module?
UPDATE
sh hw-module all attribute
Slot 0 Bay 0 Board 0 Module[ISR4451-X-4x1GE] spa_type 0x76E Daughter Board Not Present
Basic attributes : length 11, version [2], module-type [ngio-virtual], width [unknown]
Power Rating [0], Control Endpoint count [0], Daughter Board Count [0]
KR Support [0x00], 16-bit GPIO [Not present], Submodule reset support [Not required]
Extended Attributes for [Front Panel 4 ports Gigabitethernet Module]
Port Count 4 Per-port Information : Type [Ethernet] Max IID [0] Connector [RJ45] Network clocking [disable]
Module OID: 1 3 6 1 4 1 9 12 3 1 9 92 21
Port OID: 1 3 6 1 4 1 9 12 3 1 10 109