500-230: Cisco Service Provider Routing for Field Engineers

Answer: A Before configuring a VRF under MP-BGP for L3VPN service, the router must instantiate the VPNv4 or VPNv6 address family. Route distinguishers provide VPN-prefix uniqueness, whereas route targets control route import and export; their values need not match, and import and export route targets can differ. **Learn more:** [Cisco IOS XR MPLS Layer 3 VPN Configuration Guide](https://www.cisco.com/c/en/us/td/docs/routers/asr9000/software/asr9k-r7-9/lxvpn/configuration/guide/b-l3vpn-cg-asr9000-79x/implementing-mpls-layer-3-VPNs.html) · [Cisco MPLS VPN VRF CLI for IPv4 and IPv6 VPNs](https://www.cisco.com/c/en/us/td/docs/ios-xml/ios/mp_l3_vpns/configuration/xe-17/mp-l3-vpns-xe-17-book/mpls-vpn-vrf-cli-for-ipv4-and-ipv6-vpns.html)

Answer: B In Cisco IOS XR, `dumpcore` manually generates a core dump for a running or suspended process, providing diagnostic data for troubleshooting. [Cisco IOS XR System Management Command Reference](https://www.cisco.com/c/en/us/td/docs/iosxr/ncs5500/sysman/b-system-management-cr-ncs5500/b-system-management-cr-ncs5500_chapter_01016.html) **Learn more:** [Cisco IOS XR System Management Command Reference — dumpcore](https://www.cisco.com/c/en/us/td/docs/iosxr/ncs5500/sysman/b-system-management-cr-ncs5500/b-system-management-cr-ncs5500_chapter_01016.html)

Answer: B Cisco IOS XR BGP does not enable any address family by default. Each needed address family must be explicitly configured under the BGP router and, when applicable, under the neighbor. Parser defaults of IPv4 and unicast for command entry do not activate an MP-BGP address family. **Learn more:** [Cisco IOS XR BGP address family configuration and behavior](https://www.cisco.com/c/en/us/td/docs/iosxr/cisco8000/bgp/bgp-config-cisco8000/r-wrapper-core-bgp-configurations/r-bgp-address-family-configuration-and-behavior.html)