White ip doesn't work on KVM guest, what's wrong?

Question

linux

Good afternoon!
The situation is as follows: The
provider gives 2 white ip, I use one for the host system, the second for the guest.
There is a server with ubuntu 16.04 on board, it has 2 network cards, a wire from the provider comes to one network card, the second looks into the local network. Both network cards are configured in bridge modes respectively. One virtual machine looks into the local network. The second is configured with a static ip address from the provider, but the Internet does not work.
From a host the guest on white ip responds, from a guest nothing at all responds. What's wrong?
ip a

lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet 127.0.1.1/8 scope host secondary lo
       valid_lft forever preferred_lft forever

eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq master br3 state UP group default qlen 1000
    link/ether ec:eb:b8:d1:45:07 brd ff:ff:ff:ff:ff:ff

eth1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq master br1 state UP group default qlen 1000
    link/ether ec:eb:b8:d1:45:08 brd ff:ff:ff:ff:ff:ff

br1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
    link/ether ec:eb:b8:d1:45:08 brd ff:ff:ff:ff:ff:ff
    inet 192.168.0.253/24 brd 192.168.0.255 scope global br1
       valid_lft forever preferred_lft forever

virbr0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc noqueue state DOWN group default qlen 1000
    link/ether 52:54:00:99:57:20 brd ff:ff:ff:ff:ff:ff
    inet 192.168.122.1/24 brd 192.168.122.255 scope global virbr0
       valid_lft forever preferred_lft forever

virbr0-nic: <BROADCAST,MULTICAST> mtu 1500 qdisc pfifo_fast master virbr0 state DOWN group default qlen 1000
    link/ether 52:54:00:99:57:20 brd ff:ff:ff:ff:ff:ff

vnet1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast master br1 state UNKNOWN group default qlen 1000
    link/ether fe:54:00:b8:ec:6f brd ff:ff:ff:ff:ff:ff

br3: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
    link/ether ec:eb:b8:d1:45:07 brd ff:ff:ff:ff:ff:ff
    inet 188.235.xxx.xxx/24 brd 188.235.xxx.255 scope global br3
       valid_lft forever preferred_lft forever
       valid_lft forever preferred_lft forever

vnet0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast master br3 state UNKNOWN group default qlen 1000
    link/ether fe:54:00:bf:95:de brd ff:ff:ff:ff:ff:ff

brctl show

br1		8000.ecebb8d14508	no		eth1
                                              vnet1
br3		                8000.ecebb8d14507	no	        eth0
                                              vnet0
virbr0		        8000.525400995720	yes		virbr0-nic

cat /etc/network/interfaces

auto lo br1 br3 eth0 eth1

iface lo inet loopback

iface br1 inet static
      address 192.168.0.253
      netmask 255.255.255.0
      broadcast 192.168.0.255
      bridge_ports eth1
      bridge_stp off
      bridge_waitport 5

iface br3 inet static
      address 188.235.xxx.xxx
      netmask 255.255.255.0
      broadcast 188.235.xxx.255
      bridge_ports eth0
      bridge_stp off
      bridge_waitport 5

Answer 1

1. once the traffic goes in one direction, that is, it makes sense to check the firewall rules
or even reset the rules:
2. check routes and firewall on the second guest
3. listen to traffic from the guest to the host and to the Internet.
4. on the second guest, check the DNS settings of the client and check the connectivity with these DNS servers