Hello guys, I’m pulling my hair out here, so I hope you can save them. I’m not very knowledgeable when it comes to linux networking, but I decided to learn it by setting up externally accessible LXC containers. Unfortunately I got stuck. My approach right now is pretty naive, so any help with at least basic explanations will be welcome.
What I try to achieve: Setup in Vagrant, that would make containers accessible by IPs, by my local machine. So Vagrant would be the LXC host.
Host OS (Vagrant): Ubuntu 20.04
Guest OS: Debian 10
My Vagrantfile:
# -*- mode: ruby -*-
# vi: set ft=ruby :
# All Vagrant configuration is done below. The "2" in Vagrant.configure
# configures the configuration version (we support older styles for
# backwards compatibility). Please don't change it unless you know what
# you're doing.
Vagrant.configure("2") do |config|
config.vm.define "main" do |main|
main.vm.box = "bento/ubuntu-20.04"
main.vm.box_version = "202010.24.0"
main.vm.hostname = "test-luken-tech.pl"
main.vm.network "public_network", auto_config: false
main.vm.provision "shell",
run: "always",
inline: "ip address add 192.168.7.200/24 dev eth1"
main.vm.provision "shell",
run: "always",
inline: "ip address add 192.168.7.201/24 dev eth1"
main.vm.provision "shell",
run: "always",
inline: "ip address add 192.168.7.202/24 dev eth1"
main.vm.provision "shell",
run: "always",
inline: "ip link set eth1 up"
main.vm.provider :virtualbox do |vb|
vb.memory = 1024
end
main.vm.network :forwarded_port, guest: 993, host: 9930
main.vm.network :forwarded_port, guest: 587, host: 5870
end
end
There is some irrelevant stuff, like port forwarding, that can be ignored, I just put it as is.
NOTE: My local network with the gateway to the internet is: 192.168.7.0
LXC version: 4.0.4
Now, my lxd configuration I’m loading with lxd init is:
config:
core.https_address: '[::]:8443'
core.trust_password: true
networks: []
storage_pools:
- config:
source: /home/luken/lxd-storage-pools
description: ""
name: default
driver: dir
profiles:
- name: default
config: {}
description: ""
devices:
root:
path: /
pool: default
type: disk
- name: mail-server
config:
user.network-config: |
version: 2
ethernets:
eth0:
addresses:
- 192.168.7.201/32
nameservers:
addresses:
- 8.8.8.8
routes:
- to: 0.0.0.0/0
via: 169.254.0.1
on-link: true
description: Mail Server LXD profile
devices:
eth0:
ipv4.address: 192.168.7.201
nictype: routed
parent: eth0
type: nic
cluster: null
Then I launch a container with:
lxc launch ubuntu:20.04 mail-server --profile default --profile mail-server
Now pinging anything on the internet from the guest doesn’t work.
root@mail-server:~# ping 8.8.8.8
PING 8.8.8.8 (8.8.8.8) 56(84) bytes of data.
From 192.168.7.201 icmp_seq=1 Destination Host Unreachable
However it does work if I remove:
main.vm.provision "shell",
run: "always",
inline: "ip address add 192.168.7.201/24 dev eth1"
From the Vagrantfile. Any idea why is that BTW?
So here is some data about the final setup.
In the GUEST:
root@mail-server:~# ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
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
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
2: eth0@if4: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
link/ether aa:db:f6:d2:02:7f brd ff:ff:ff:ff:ff:ff link-netnsid 0
inet 192.168.7.201/32 brd 255.255.255.255 scope global eth0
valid_lft forever preferred_lft forever
inet6 fe80::a8db:f6ff:fed2:27f/64 scope link
valid_lft forever preferred_lft forever
root@mail-server:~# ip r
default via 169.254.0.1 dev eth0 proto static onlink
In the HOST:
luken@test-luken-tech:~$ ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
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
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000
link/ether 08:00:27:be:4a:e8 brd ff:ff:ff:ff:ff:ff
inet 10.0.2.15/24 brd 10.0.2.255 scope global dynamic eth0
valid_lft 84632sec preferred_lft 84632sec
inet6 fe80::a00:27ff:febe:4ae8/64 scope link
valid_lft forever preferred_lft forever
3: eth1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP group default qlen 1000
link/ether 08:00:27:79:ce:6c brd ff:ff:ff:ff:ff:ff
inet 192.168.7.200/24 scope global eth1
valid_lft forever preferred_lft forever
inet 192.168.7.201/24 scope global secondary eth1
valid_lft forever preferred_lft forever
inet 192.168.7.202/24 scope global secondary eth1
valid_lft forever preferred_lft forever
inet6 fe80::a00:27ff:fe79:ce6c/64 scope link
valid_lft forever preferred_lft forever
4: veth4d0dc658@if2: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
link/ether fe:b7:0d:57:e7:a4 brd ff:ff:ff:ff:ff:ff link-netnsid 0
inet 169.254.0.1/32 scope global veth4d0dc658
valid_lft forever preferred_lft forever
inet6 fe80::fcb7:dff:fe57:e7a4/64 scope link
valid_lft forever preferred_lft forever
luken@test-luken-tech:~$ ip r
default via 10.0.2.2 dev eth0 proto dhcp src 10.0.2.15 metric 100
10.0.2.0/24 dev eth0 proto kernel scope link src 10.0.2.15
10.0.2.2 dev eth0 proto dhcp scope link src 10.0.2.15 metric 100
192.168.7.0/24 dev eth1 proto kernel scope link src 192.168.7.200
192.168.7.201 dev veth4d0dc658 scope link
My question is very simple, and I think answer for it would be extremely helpful for anyone starting his adventure with LXC containers and networking:
How to make the container accessible from my local computer under the IP 192.168.7.201 by using “routed” nictype? I assumed it will be pretty strightforward, but it doesn’t appear like that 
.
.