Can this two hosts ping/access each other without routing?
Host A:
172.17.1.1
255.255.255.0
N-ID: 172.17.1.0
BC: 172.17.1.255
Host B:
172.17.1.10
255.255.0.0
N-ID: 172.17.0.0
BC: 172.17.255.255
Yes, both machines think they are on same network, as the subnet mask includes both addresses on both hosts.
Related
I installed Ubuntu 16.04 Server on a machine with 4 network cards. I have interfaces eth0 and eth1 connected to the same switch. The interface eth0 is meant for the remote SSH connection to manage the server. I want to use eth1 to be bridged by br0. This bridge I want to use for LXC containers. This setup in a DHCP environment did not cause me any problems. The challenge is that the network this server is installed in is fully static. I received an IP range for this server with same subnet mask and gateway.
Setting up eth0 was no problem:
auto eth0
iface eth0 inet static
address 195.x.x.2
network 195.x.x.0
netmask 255.255.255.0
gateway 195.x.x.1
broadcast 195.x.x.255
dns-nameservers 150.x.x.105 150.x.x.106
The problem comes with the second interface eth1, because it has the same gateway as eth0 Ubuntu warns that only one default gateway can be set (which is logical). Therefor I had set eth1 as follows:
auto eth1
iface eth1 net static
address 195.x.x.3
network 195.x.x.0
netmask 255.255.255.0
broadcast 195.x.x.255
Problem with this setup is that I can externally ping eth0 at IP 195.x.x.2 but eth1 cannot be pinged or accessed via SSH. I managed to make it work with a lot of routing trickery but as many articles write on this that this way is a hole which gets deeper if you have static bridge and containers for this.
My question is: Does anyone has a straight forward approach for my issue? How should I configure eth0 and eth1 to normally bridge the containers to eth1 with static IP numbers?
Ok I solved it in the following manner, by still proceeding with the gateway routing solution as described in the question. Maybe people with the same issue could use this approach as well or if somebody knows a better solution feel free to comment.
On the host:
I enabled ARP filtering:
sysctl -w net.ip4.conf.all.arp_filter=1
echo "net.ipv4.conf.all.arp_filter = 1" >> /etc/sysctl.conf
Configured the /etc/network/interfaces:
auto lo
iface lo net loopback
# The primary network interface
auto etc0
iface eth0 inet static
address 195.x.x.2
network 195.x.x.0
netmask 255.255.255.0
gateway 195.x.x.1
broadcast 195.x.x.255
up ip route add 195.x.x.0/24 dev eth0 src 195.x.x.2 table eth0table
up ip route add default via 195.x.x.1 dev eth0 table eth0table
up ip rule add from 195.x.x.2 table eth0table
up ip route add 195.x.x.0/24 dev eth0 src 195.0.0.2
dns-nameservers 150.x.x.105 150.x.x.106
# The secondary network interface
auto eth1
iface eth1 net manual
# LXC bridge interface
auto br0
iface br0 inet static
address 195.x.x.3
network 195.x.x.0
netmask 255.255.255.0
bridge_ifaces eth1
bridge_ports eth1
bridge_stp off
bridge_fd 0
bridge_maxwait 0
up ip route add 195.x.x.0/24 dev br0 src 195.x.x.3 table br0table
up ip route add default via 195.x.x.1 dev br0 table br0table
up ip rule add from 195.x.x.3 table br0table
up ip route add 195.x.x.0/24 dev br0 src 195.0.0.3
Added the following lines to /etc/iproute2/rt_tables:
...
10 et0table
20 br0table
At the container config file (/var/lib/lxc/[container name]/config):
...
lxc.network.type = vets
lxc.network.link = br0
lxc.network.flags = up
lxc.network.hwadr = [auto create when bringing up container]
lxc.network.ipv4 = 195.x.x.4/24
lxc.network.ipv4.gateway = 195.x.x.1
lxc.network.veth.pair = [readable server name] (when using ifconfig)
lxc.start.auto = 0 (1 if you want the server to autostart)
lxc.start.delay = 0 (fill in seconds you want the container to wait before start)
I tested it by enabling apache2 on the container and accessed the webpage from outside the network. Hope it helps anybody who bumps into the same challenge I did.
PS: Do not forget if you choose to have the container's config file to assign the IP, that you disable it in the interface file of the container itself.
auto lo
iface lo inet loopback
auto eth0
iface eth0 net manual
I have 1 host with ip 10.120.194.214/24
And I have a range set from my router to my host ip, the range is 10.120.187.0/24 and his gateway is 10.120.187.1
I'm trying to create a docker network with this range
docker network create --driver=bridge --subnet=10.120.187.0/24 --ip- range=10.120.187.128/25 --gateway=10.120.187.254 -o "com.docker.network.bridge.enable_icc=true" -o "com.docker.network.bridge.host_binding_ipv4"="10.120.187.1" mypublicnet
if I try to ping to 10.120.187.254 from the LAN i don't receive ping
the host configuration is this
iface eth0 inet manual
auto vmbr0
iface vmbr0 inet static
address 10.120.194.214
netmask 255.255.255.0
gateway 10.120.194.1
bridge_ports eth0
bridge_stp off
bridge_fd 0
bridge_maxwait 0
dns-nameservers 10.120.194.1 10.120.194.10
The idea is that I can run containers with ip accesible from the LAN, Every container must have diferent ip.
Contrary to what you think, docker bridge network is not bridged to the physical interface, but is NATed.
To achieve what you are asking for in production, use Pipework or, if you are cutting edge, you can try the docker macvlan driver which is, for now, experimental.
I am new to openstack and I followed the installation guide of icehouse for ubuntu 12.04/14.04
I chose 3 node architecture. Controller, Nova, Neutron.
The 3 nodes are installed in VM's. I used nested KVM. Inside VM's kvm is supported so nova will use virt_type=kvm. In controller I created 2 nics. eth0 is a NAT interface with ip 203.0.113.94 and eth1 a host only interface with ip 10.0.0.11.
In nova there are 3 nics. eth0 NAT - 203.0.113.23, eth1 host only 10.0.0.31 and eth2 another host only 10.0.1.31
In neutron 3 nics. eth0 NAT 203.0.113.234, eth1 host only 10.0.0.21 and eth2 another hosty only 10.0.1.21 (during installation guide in neutron node i created a br-ex (and a port to eth0) which took the settings of eth0 and eth0 settings are:
auto eth0 iface eth0 inet manual up ifconfig $IFACE 0.0.0.0 up
up ip link set $IFACE promisc on
down ip link set $IFACE promisc off
down ifconfig $IFACE down)
Everything seemed fine. I can create networks, routers etc, boot instances but I have this error.
When I launch an instance it takes a fixed ip but when I log in into instance (cirros) can't ping anything. ifconfig with no ip.
I noticed that in demo-net (tenant network) properties under subnet in the ports field it has 3 ports. 172.16.1.1 network:router_interface active 172.16.1.3 network:dhcp active 172.16.1.6 compute:nova down
I searched for solutions over the net but couldn't find anything!
Any help?
Ask me if you want specific logs because I don't know which ones to post!
Thanks anyway!
Looks like you are using Fixed IP to ping..If so please assign floating IP to your instance, and then try to ping..
If you have already assigned floating IP and you are pinging using that IP..please upload log of your instance
I need some information about routing public IP addresses assigned to the hypervisor into a VM.
I have installed XEN hypervisor on Centos 6.5, I have one NIC with IP 80.86.84.34 & Mask:255.255.255.0 I have an additional IP 85.25.14.195 & Mask: 255.255.255.255
Dom0 has eth0 & virbr0 with a virtual dhcp, the VM has address 192.168.122.4 & Mask:255.255.255.0 the VM has working outbound internet connection.
How do I correctly set dom0 to route connections for 85.25.14.195 into the VM?
Many thanks for your help and apologies if this is a basic question that has been answered before, please point me in the right direction.
First EDIT
I have managed to route the public IP by adding the below route in Dom0, DomU now correctly responds to packets received by Dom0 for the public IP forwarded over virbr0.
route add -net 85.25.14.195 gw 192.168.122.1 netmask 255.255.255.255
My follow up question is what rule is required in IP tables to allow traffic? As currently it is blocked when the firewall is running.
Second EDIT
OK, so I figured out the iptables, I had to remove the REJECT line on virbr0, I also had to add the following rule to make the outbound IP from Dom0 appear correctly:
-A POSTROUTING -s 192.168.122.2 -p tcp -j SNAT --to 85.25.14.195
You should be able to assign 85.25.14.195 as alias IP on virbr0 ( may be virbr0:1 ) and do simple IP Nat or forwarding. You need to do # sysctl -w net.ipv4.ip_forward=1 to be able to forward traffic coming on Public IP to internal Private IP.
Settings in /etc/network/interfaces seems to have no effect on my BeagleBone Black Version C. I want to set my beaglebone black's ethernet IP address to a static IP as I have done with all my other internet-of-things devices running Debian. I edited /etc/network/interfaces as I have before, but I do not see any changes via ifconfig. This is after a restart of networking AND a restart of the beaglebone. I have googled somewhat, and posted to the beaglebone forums after searching them, and I still do not have a solution. I noticed a commented line in interfaces suggesting that the settings are set via an init script, but this is where I get a little lost. I have moderate knowledge of Debian, but I have not peeled back enough layers apparently. I am connecting my beaglebone black via ethernet connector. WIFI is a beast I will tackle later.
I set my router to reserve a specific IP based on MAC ID, but I would like to know what I am missing here.
iface usb0 inet static
address 192.168.0.103
netmask 255.255.255.0
network 192.168.0.0
gateway 192.168.0.1
iface eth0 inet static
address 192.168.0.102
netmask 255.255.255.0
network 192.168.0.0
gateway 192.168.0.1
You are missing the auto line
auto eth0
iface eth0 inet static
address 192.168.0.102
netmask 255.255.255.0
network 192.168.0.0
gateway 192.168.0.1
(Just for diagnosis) - Also remove the gateway line from it
and after you get the connection run this command to add the gateway
root prompt :) #
route add default gateway 192.168.0.1
i was playing around a lot with networking on it so i got the answer. Hope this resolve your issue do post.
Do the configurations in wicd. Run "wicd-client" which opens GUI to make the configuration. Apparently wicd configurations overwrite what you do in /etc/network/interfaces
Another alternative to setting the ipaddress to be static on boot. Even without a ethernet jack plugged in, which was my issue.
Caution: this is hacky, and there probably better streamlined approach
Edit the /opt/scripts/boot/autoconfigure_usb0.sh script
line 92 and 139 set the usb0 default ipaddress
/sbin/ifconfig usb0 ${deb_usb_address} netmask ${deb_usb_netmask} || true
insert the following line after it, in both places
/sbin/ifconfig usb0 ${deb_usb_address} netmask ${deb_usb_netmask} || true
/sbin/ifconfig eth0 192.168.0.123 netmask 255.255.255.0 || true
then it will boot up with that as the static IP address even if you don't have anything plugged it.