user6758's questions

I have two devices with embedded Linux. One of them (machine A) has two network interfaces: eth that is used to connect machines together and wlan interface to connect to router via WiFi. The second machine (B) has only one eth interface. My goal is to enable access to WiFi networks on machine B. I used some iptables rules to filter packets from machine A to machine B and it works. Now, I need to block dhcp traffic on the first machine so that it does not reach the second machine. I was looking for some iptables rules to do it but I found that it is impossible with iptables. Is there any other way to block that traffic?

Thank you in advance for any help.

I have two virtual machines with Ubuntu Server 20.04. One of these virtual machines is a DHCPv6 server, and the other one is a client. I am able to set an IPv6 address on the client, but I cannot ping to and from this address. ip -6 route shows this address but with prefix length of 128. I would like to have the prefix length equals to 64, the same as the server IP address has. When I add to my routing table on the client IP address obtained from the server but with prefix length equals to 64, I can ping between my virtual machines.

This is my /etc/dhcp/dhcpd6.conf file on the server:

default-lease-time 2592000;
preferred-lifetime 604800;
option dhcp-renewal-time 3600;
option dhcp-rebinding-time 7200;
allow leasequery;
option dhcp6.name-servers 3ffe:501:ffff:100:200:ff:fe00:3f3e;
option dhcp6.domain-search "test.example.com","example.com";
option dhcp6.info-refresh-time 21600;

authoritative:
subnet6 fdaa:a:a:a::/64 {
   range6 fdaa:a:a:a::100 fdaa:a:a:a::199;
}

The last three lines were added by me.

This is my /etc/netplan/00-installer-config.yaml file on the client:

network:
   ethernets:
      ens3:
         dhcp4: false
         dhcp6: true
   version: 2

Thank you in advance for any help.

I have two Qemu virtual machines with Ubuntu Server. I would like one of them to be a DHCP server. On the second one, I would like to have two IPv6 addresses. One should be static, and the other one should be obtained from my DHCP server. I am able to create many static addresses, but when I get a dynamic one, I lose all my static addresses except a link-local one. What should I do to have both static and dynamic IPv6 addressess on one interface?

Thank you in advance for any help.

My goal is to connect a virtual machine A with a virtual machine C through a virtual machine B that has two interfaces. When I create a bridge on these two interfaces I can ping A<-->C but I cannot ping from A<-->B and B<-->C. If the bridge works in layer 2, is it possible to ping to interfaces that are part of the bridge?

Thank you in advance for your answers.