See all of the guides.

Part 5: Advanced Networking

Networking Basics

Devices use biosdevname (enp3s0f0)

User ip link to view interfaces

nmcli is your friend. nmcli tab tab will show you the way.

nmcli connection add con-name enp3s0f2 ipv4.addresses 172.16.0.2/24 ifname enp3s0f2 type ethernet method=manual

Bridges

Create a new bridge.

nmcli connection add type bridge ifname Guests

Add ports

nmcli con add type ethernet con-name br-guest0 ifname enp3s0f0 master Guests

nmcli con add type ethernet con-name br-guest1 ifname enp3s0f1 master Guests

brctl show

brcrl show output

Routing

ip route show - Print current route table

ip route add 10.10.10.0/24 via 192.168.1.12/2 - Add static route to runtime

Edit /etc/sysconfig/network-scripts/route-ifname - Add persistently route

add a line: 10.0.0.0/24 via 192.168.4.20 dev device

Teaming

Starting a team doesn't bring up a slave port.

Starting a slave port will start the team.

See examples - man nmcli-examples

ls /usr/share/doc/teamd-1.27/example_configs

cp /usr/share/doc/teamd-1.27/example_configs/broadcast.conf team0.json

vim team0.json

{
"device":        "team0",
"runner":        {"name": "broadcast"},
"ports":        {"enp3s0f0": {}, "enp3s0f1": {}}
}

nmcli con add type team con-name Team1 ifname Team1 config team0.json

nmcli con add type team-slave con-name Team0-s1 ifname enp3s0f0 master Team0


nmcli con add type team-slave con-name Team0-s2 ifname enp3s0f1 master Team0

teamctl team0 state

reboot the node.

Add a VLAN.

This example will add vlan 10 to device team0 called corp

nmcli con add type vlan con-name corp ifname team0.10 dev team0 id 10

Bring up an interface

nmcli con up team0

teamdctl team0 state

IPv6 Basics

  • 128bit addresses
  • Leading zeros can be omitted
    fe80::1
  • Default subnet /64
  • Ports are defined with address in square brackets
    [fe80::1]:80
    This example is localhost port 80
  • MAC address may be part of the node bits.

Predefined Address Spaces

  • ::1/128 - localhost
  • :: - unspecified address (0.0.0.0)
  • ::/0 - default route
  • 2000::/3 - global unicast address
  • fd00::/8 - unique local address
  • fe80::/64 - link-local address
  • ff00::/8 - multicast
  • No more broadcasts

Obtaining addresses

  • nmcli used for static addressing
  • fe80:: is used by default
  • DHCPv6
    muticast sent to ff02::1:2 port 547/UDP (All DHCP Server Multicast)
    DHCP server sends packet to client port 548/UDP
  • SLAAC - Stateless Address Auto Configuration
    Router solicitation sent to ff02::2 (All routers multicast)
    Router provides address to host with network prefix (radvd needed)

Setting a manual address

nmcli con modify eth0 ipv6.method manual ipv6.addr fd00:201/64

nmcli con modify eth0 +ipv6.dns fd00:200/64

Setting the method is extremely important.