Lab 16.1 - LXC - no network in containers, cgroup controller missing

Hi,
I'm trying to follow the LXC lab but after some trials and google searching I'm still with no networking containers.

Here my configs:

root@alex-kvm:~# hostnamectl status
 Static hostname: alex-kvm
       Icon name: computer-vm
         Chassis: vm
      Machine ID: 842c7ef66a9c4d7b88ec23e7c342ce7c
         Boot ID: 11ef0d3089fa49f9b8b6dd474f04c73e
  Virtualization: kvm
Operating System: Ubuntu 21.10                    
          Kernel: Linux 5.13.0-20-generic
    Architecture: x86-64
 Hardware Vendor: QEMU
  Hardware Model: Standard PC _Q35 + ICH9, 2009_

root@alex-kvm:~# lxc-checkconfig 
LXC version 4.0.10
Kernel configuration not found at /proc/config.gz; searching...
Kernel configuration found at /boot/config-5.13.0-20-generic
--- Namespaces ---
Namespaces: enabled
Utsname namespace: enabled
Ipc namespace: enabled
Pid namespace: enabled
User namespace: enabled
Network namespace: enabled

--- Control groups ---
Cgroups: enabled
Cgroup namespace: enabled

Cgroup v1 mount points: 


Cgroup v2 mount points: 
/sys/fs/cgroup

Cgroup v1 systemd controller: missing
Cgroup v1 freezer controller: missing
Cgroup ns_cgroup: required
Cgroup device: enabled
Cgroup sched: enabled
Cgroup cpu account: enabled
Cgroup memory controller: enabled
Cgroup cpuset: enabled

--- Misc ---
Veth pair device: enabled, loaded
Macvlan: enabled, not loaded
Vlan: enabled, not loaded
Bridges: enabled, loaded
Advanced netfilter: enabled, loaded
CONFIG_NF_NAT_IPV4: missing
CONFIG_NF_NAT_IPV6: missing
CONFIG_IP_NF_TARGET_MASQUERADE: enabled, not loaded
CONFIG_IP6_NF_TARGET_MASQUERADE: enabled, not loaded
CONFIG_NETFILTER_XT_TARGET_CHECKSUM: enabled, loaded
CONFIG_NETFILTER_XT_MATCH_COMMENT: enabled, not loaded
FUSE (for use with lxcfs): enabled, not loaded

--- Checkpoint/Restore ---
checkpoint restore: enabled
CONFIG_FHANDLE: enabled
CONFIG_EVENTFD: enabled
CONFIG_EPOLL: enabled
CONFIG_UNIX_DIAG: enabled
CONFIG_INET_DIAG: enabled
CONFIG_PACKET_DIAG: enabled
CONFIG_NETLINK_DIAG: enabled
File capabilities: 

Note : Before booting a new kernel, you can check its configuration
usage : CONFIG=/path/to/config /usr/bin/lxc-checkconfig

# lxc-create -n ubby -t ubuntu -o /var/log/lxc/lxc-ubby.log

lxc-start --version => 4.0.10

# lxc-start -n ubby -F /bin/bash

root@ubby:/# ping google.com
ping: google.com: Temporary failure in name resolution

root@ubby:/# ip addr show
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@if19: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
    link/ether 00:16:3e:e9:a6:0c brd ff:ff:ff:ff:ff:ff link-netnsid 0
    inet6 fe80::216:3eff:fee9:a60c/64 scope link 
       valid_lft forever preferred_lft forever

root@ubby:/# ip route
root@ubby:/# 
root@ubby:/# cat /etc/hosts
127.0.0.1   localhost
127.0.1.1   ubby

# The following lines are desirable for IPv6 capable hosts
::1     ip6-localhost ip6-loopback
fe00::0 ip6-localnet
ff00::0 ip6-mcastprefix
ff02::1 ip6-allnodes
ff02::2 ip6-allrouters

# cat /proc/1/mounts |grep cgroup
cgroup2 /sys/fs/cgroup cgroup2 rw,nosuid,nodev,noexec,relatime 0 0

Following this issue I have also tried to run the lxc-start inside a systemd-run command, but being in a kvm machine it doesn't work

# systemd-run --user --scope -p "Delegate=yes" lxc-start -n ubby -F /bin/bash
Failed to connect to bus: $DBUS_SESSION_BUS_ADDRESS and $XDG_RUNTIME_DIR not defined (consider using --machine=<user>@.host --user to connect to bus of other user)

Any help?