OSPFv2 graceful restart (GR) is enabled by default, and can be disabled on a routing device.
device# configure terminal
device(config)# router ospf
device(config-router-ospf-vrf-default-vrf)# no graceful-restart
The following example disables GR.
device# configure terminal device(config)# router ospf device(config-router-ospf-vrf-default-vrf)# no graceful-restart