#!/bin/bash

#egress interface, this should be part of bridge.
INTERFACE="eth3"
MTU_SIZE=1986
#this IP can be set on incoming nic interface .
MY_IP="2002:b001:1001:2000::1"
setup_gre_tunnel(){
    echo "Setting up tunnel $1 with remote end $2"
    ip link add "$1" type ip6gretap remote "$2" local "$3" ttl 255
    ip link set dev "$1" mtu "$MTU_SIZE"
    ip link set dev "$1" master br0
    sleep 5
    ip link set dev "$1" up
}
IDX=1
# Add CN lo v6 address here
declare -a remote_ips=(
"2002:b001:1001:2002::10"
"2002:b001:1001:2002::12"
)

 # Create a bridge  containing uplink nic interface
 ip link add name br0 type bridge
 #remove any L3 address associated on this interface
 ip -4 addr flush dev "$INTERFACE" 2>/dev/null
 ip -6 addr flush dev "$INTERFACE" 2>/dev/null
 #bring down the interface so that routes get deleted
 ip link set dev "$INTERFACE" down 2>/dev/null
 #add to bridge
 ip link set dev "$INTERFACE" master br0 2>/dev/null
 ip link set dev "$INTERFACE" up 2>/dev/null
 # in the end enable bridge
 ip link set dev br0 up


# Add all l2gre in this bridge
for i in "${remote_ips[@]}"
do
   setup_gre_tunnel l2gre$IDX "$i" "$MY_IP"
   IDX=$(($IDX + 1))
done