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- If set protocols ospf network area has been configured on the device first, you have to delete it before configuring command set protocols ospf interface area.
- If set protocols ospf vrf interface area has been configured on the device first, and if the configuration is in a specified VRF, you have to delete all OSPF configurations under the specified VRF by using command delete protocols ospf vrf before before configuring the command set protocols ospf vrf network area. Or if these configurations are in the default VRF, you have to delete all OSPF configurations of all VRFs on the device by using command delete protocols ospf before configuring set protocols ospf network area.
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