build a bgp config for backing anycast

wow.sh

#!/bin/bash

apt-get install -y bird jq

# Ask for the metadata of the VM to build the bird config
curl http://169.254.169.254/v1.json -o /tmp/serverdata.json

RID=$(cat /tmp/serverdata.json | jq -r '.bgp.ipv4."my-address"')

echo "router id $RID;" > /tmp/bird6.conf


REGION=$(echo -n 0)
DEPLOYMENT=$(echo -n 0)
LOCALAS=$(cat /tmp/serverdata.json | jq -r '.bgp.ipv6."my-asn"')
LOCALIP=$(cat /tmp/serverdata.json | jq -r '.bgp.ipv6."my-address"')
AIRPORTCODE=$(cat /tmp/serverdata.json | jq -r .region.regioncode)

case "$AIRPORTCODE" in
        LHR)
            REGION=1 # EU
            DEPLOYMENT=1
            ;;

        AMS)
            REGION=1 # EU
            DEPLOYMENT=2
            ;;

        CDG)
            REGION=1 # EU
            DEPLOYMENT=3
            ;;

        FRA)
            REGION=1 # EU
            DEPLOYMENT=4
            ;;

        EWR) # New Jersy USA
            REGION=2 # E USA
            DEPLOYMENT=1
            ;;
         
        MIA) # Miami USA
            REGION=2 # E USA
            DEPLOYMENT=2
            ;;
         
        ATL) # Atlanta USA
            REGION=2 # E USA
            DEPLOYMENT=3
            ;;

        ORD) # Chicago USA
            REGION=2 # E USA
            DEPLOYMENT=4
            ;;

        SJC) # Bay area USA
            REGION=3 # W USA
            DEPLOYMENT=1
            ;;

        LAX) # Los Angeles USA
            REGION=3 # W USA
            DEPLOYMENT=2
            ;;

        SEA) # Seattle USA
            REGION=3 # W USA
            DEPLOYMENT=3
            ;;

        DFW) # Dallas USA
            REGION=3 # W USA
            DEPLOYMENT=4
            ;;

        NRT) # Tokyo Asia
            REGION=4 # Asia
            DEPLOYMENT=1
            ;;

        SGP) # Singapore
            REGION=4 # Asia
            DEPLOYMENT=2
            ;;

        SYD) # Sydney, Kind of Asia for the case of testing
            REGION=4 # Asia
            DEPLOYMENT=3
            ;;
esac

cat <<EOF | tee /tmp/generic
protocol kernel {
	persist;		# Don't remove routes on bird shutdown
	scan time 20;		# Scan kernel routing table every 20 seconds
    export none;
    import none;
}

protocol device {
	scan time 10;		# Scan interfaces every 10 seconds
}
EOF

cat <<EOF | tee /tmp/bgpsession
protocol bgp vultr
{
    local as $LOCALAS;
    source address $LOCALIP;
    import none;
    graceful restart on;
    multihop 2;
    neighbor 2001:19f0:ffff::1 as 64515;
    password "xxxxxxxxx";
EOF

echo "    export filter {" >> /tmp/bgpsession

cat /tmp/generic >> /tmp/bird6.conf

echo "protocol static" > /tmp/statics
echo "{" >> /tmp/statics

HACK="0"

for UserGroup in {1..2};
do
    printf "\troute 2a07:1500:$UserGroup$HACK$HACK$HACK::/36 via $LOCALIP;\n"
    ip -6 route add local "2a07:1500:$UserGroup$HACK$HACK$HACK::/36" dev lo
    printf "\troute 2a07:1500:$UserGroup$REGION$HACK$HACK::/40 via $LOCALIP;\n"
    printf "\troute 2a07:1500:$UserGroup$REGION$DEPLOYMENT$HACK::/44 via $LOCALIP;\n"
    for Link in {"1,2914","2,174","3,3356","4,1299","5,2516","6,3257","7,6939","8,63956","9,17819","A,7922","B,0"};
    do
        address=$(echo $Link | awk -F "," '{print $1}')
        upstream=$(echo $Link | awk -F "," '{print $2}')
        printf "\troute 2a07:1500:$UserGroup$REGION$DEPLOYMENT$address::/48 via $LOCALIP;\n"
        if [ "$upstream" -eq "0" ]
        then
            printf "\tif (net = 2a07:1500:$UserGroup$REGION$DEPLOYMENT$address::/48) then {$TRANSITLIST }\n" >> /tmp/bgpsession
        else
            printf "\tif (net = 2a07:1500:$UserGroup$REGION$DEPLOYMENT$address::/48) then { bgp_community.add((20473,6000)); bgp_community.add((64699,$upstream)); }\n" >> /tmp/bgpsession
            TRANSITLIST=$(printf "$TRANSITLIST bgp_community.add((64600,$upstream));")
        fi
    done
done >> /tmp/statics

echo "}" >> /tmp/statics
echo "accept;};}" >> /tmp/bgpsession

cat /tmp/statics >> /tmp/bird6.conf
cat /tmp/bgpsession >> /tmp/bird6.conf

cp /tmp/bird6.conf /etc/bird/bird6.conf
systemctl restart bird6