$ ping -I <source IP in VRF>  <destination IP>
$ ping6 -I <vrf> -I <source IP> <destination IP>
$ ping6 -I <source IP in vrf> <destination IP>

iputils-20210202-9.el9.x86_64

#!/bin/bash
# create namespaces
sysctl -w net.ipv6.conf.all.forwarding=1
ip netns add ns2
ip -net ns2 link set lo up
ip netns add ns3
ip -net ns3 link set lo up
# create veth devices
ip link add veth2 type veth peer name veth3
# set them to nss
ip link set veth2 netns ns2
ip link set veth3 netns ns3
# add vlan and ips for ns2
ip netns exec ns2 ip link add link veth2 name veth2.100 type vlan id 100
ip netns exec ns2 ip link set veth2 up
ip netns exec ns2 ip link set lo up
ip netns exec ns2 ip link set veth2.100 up
ip netns exec ns2 ip addr add 192.168.90.102/24 dev veth2.100
# create vrf
ip netns exec ns2 ip link add vrf-2 type vrf table 1002
ip netns exec ns2 ip link set vrf-2 up
# set the lvan interface to the vrf
ip netns exec ns2 ip link set dev veth2.100 master vrf-2
# ipv6 
ip netns exec ns2 ip -6 addr add 2222::102/64 dev veth2.100
# add vlan and ips for ns3
ip netns exec ns3 ip link add link veth3 name veth3.100 type vlan id 100
ip netns exec ns3 ip addr add 192.168.90.103/24 dev veth3.100
ip netns exec ns3 ip link set veth3 up
ip netns exec ns3 ip link set veth3.100 up
ip netns exec ns3 ip link set lo up
# create vrf
ip netns exec ns3 ip link add vrf-3 type vrf table 1003
ip netns exec ns3 ip link set vrf-3 up
# set the lvan interface to the vrf
ip netns exec ns3 ip link set dev veth3.100 master vrf-3
# ipv6
ip netns exec ns3 ip -6 addr add 2222::103/64 dev veth3.100
sleep 2
echo ping_group_range: should not be 1 0
cat /proc/sys/net/ipv4/ping_group_range
echo
echo IPv4 test--
echo
echo "test1: ping -I <vrf> -I <source IP> <destination IP>"
ip netns exec ns2 ping -c3 -I vrf-2 -I 192.168.90.102 192.168.90.103
echo
echo "test2: ping -I <vrf> <destination IP>"
ip netns exec ns2 ping -c3 -I vrf-2 192.168.90.103
echo
echo "test3: ping -I <source IP in VRF>  <destination IP>"
ip netns exec ns2 ping -c3  -I 192.168.90.102 192.168.90.103
echo
echo
echo IPv6 test--
echo "test5: ip vrf exec <vrf> ping6 -I <source IP> <destination IP>"
ip netns exec ns2 ip vrf exec vrf-2 ping6 -c3 -I 2222::102 2222::103
echo
echo "test6: ping6 -I <vrf> -I <source IP> <destination IP>"
ip netns exec ns2 ping6 -c3 -I vrf-2 -I 2222::102 2222::103
echo
echo "test7: ping -I <vrf> <destination IP>"
ip netns exec ns2 ping6 -c3 -I vrf-2 2222::103
echo
echo "test8: ping6 -I <source IP in vrf> <destination IP>"
ip netns exec ns2 ping6 -c3 -I 2222::102 2222::103
echo
echo remove all ---
ip netns pids ns2 | xargs -r kill
ip netns del ns2
ip netns pids ns3 | xargs -r kill
ip netns del ns3
ip netns lista