In this case Using Cisco ISR 1841 15.1(4)M10.
ipv6 unicast-routing ipv6 nd ra suppress ! or ipv6 nd ra suppress all
R3#conf t Enter configuration commands, one per line. End with CNTL/Z. R3(config)#ipv6 uni R3(config)#ipv6 unicast-routing R3(config)#int f0/1 R3(config-if)#ipv6 nd ra su R3(config-if)#ipv6 nd ra suppress a R3(config-if)#ipv6 nd ra suppress ? all Suppress all IPv6 Router Advertisements <cr> R3(config-if)#ipv6 nd ra suppress all R3(config-if)#ipv6 nd ra suppress all R3(config-if)#int f0/0 R3(config-if)#no ipv R3(config-if)#no ipv6 nd R3(config-if)#no ipv6 nd ra R3(config-if)#no ipv6 nd ra su R3(config-if)#no ipv6 nd ra suppress R3(config-if)#^Z R3#sh ru *Jul 9 00:36:19.443: %SYS-5-CONFIG_I: Configured from console by console R3#sh run | i ipv6 ipv6 unicast-routing ipv6 cef ipv6 nd ra suppress all R3#sh run int f0/0 Building configuration... Current configuration : 83 bytes ! interface FastEthernet0/0 no ip address shutdown duplex auto speed auto end R3#sh run int f0/1 Building configuration... Current configuration : 108 bytes ! interface FastEthernet0/1 no ip address shutdown duplex auto speed auto ipv6 nd ra suppress all end R3#
R3#conf t Enter configuration commands, one per line. End with CNTL/Z. R3(config)#int f0/0 R3(config-if)#ipv R3(config-if)#ipv6 nd R3(config-if)#ipv6 nd ma R3(config-if)#ipv6 nd managed-config-flag R3(config-if)#ipv R3(config-if)#ipv6 nd other R3(config-if)#ipv6 nd other-config-flag R3(config-if)#