Re: BGP configuration

The main difference is the first set of parameters will apply specifically to neighbor 2600:1:4006::6 within the group. The second set applies to the entire group i.e. additional neighbor statements can be added thus inheriting group-wide parameters. Note hierarchical stanza below:

1st:

WWW {
    protocols {
        bgp {
            group ASV6 {
                neighbor 2600:1:4006::6 {
                    description "eBGP peer";
                    multihop {
                        ttl 2;
                    }
                    local-address 2600:1:4006::1;
                    import C1_V6; ## 'C1_V6' is not defined
                    family inet6 {
                        unicast;
                    }
                    export DC1_V6; ## 'DC1_V6' is not defined
                    remove-private;
                    peer-as 478;
                }
            }
        }
    }
}

2nd:

WWW {
    protocols {
        bgp {
            group ASV6 {
                description "eBGP peer";
                multihop {
                    ttl 2;
                }
                import C1_V6; ## 'C1_V6' is not defined
                family inet6 {
                    unicast;
                }
                export DC1_V6; ## 'DC1_V6' is not defined
                remove-private;
                peer-as 478;
                neighbor 2600:1:4006::6 {
                    local-address 2600:1:4006::1;
                }
            }
        }
    }
}