multi container ping failed

My project requires multiple container environments, and each lxc needs to be able to ping with each other. I use settings similar to the following

config.vm.define :"lxc1" do |node_conf|
    node_conf.vm.network "private_network", ip: "192.168.45.2",lxc__bridge_name: "project"
    ...
end

config.vm.define :"lex2" do |node_conf|
    node_conf.vm.network "private_network", ip: "192.168.42.3",lxc__bridge_name: "project"
    ...
end

Host can ping each container,

root@lxc:~/lxc/vagrantlxcTest# ping 192.168.42.3
PING 192.168.42.3 (192.168.42.3) 56(84) bytes of data.
64 bytes from 192.168.42.3: icmp_seq=1 ttl=64 time=0.059 ms
64 bytes from 192.168.42.3: icmp_seq=2 ttl=64 time=0.037 ms

but I can't ping from one container to another,

vagrant@lxc1:~$ ping 192.168.42.3
PING 192.168.42.3 (192.168.42.3) 56(84) bytes of data.

Do I need to add other settings to do that?

I did not do any settings for the project bridge, which is directly used.

I use default lxcbr0 and match the appropriate IP allows the containers to ping each other

I would very appreciate it if you guys can give me some advice or solutions.

fgrehm / vagrant-lxc

multi container ping failed #487