In Linux NetworkingLinux Networking
This note serves as a link to connect Linux Networking related notes.
Get started on the topic by checking one of these out:
[[How to make a Linux Host act as a Router]]
Some of the useful ne..., the most basic form of a network is two PCs connected with a switch.
In order for machines to connect to a switch, we need an interface on each host (these can be physical or virtual). To see the interfaces on the host, we can run the following:
ip link
#> 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN mode DEFAULT group default qlen 1
#> link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
#> 2: ens3: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP mode DEFAULT group default qlen 1000
#> link/ether 02:42:ac:11:00:0a brd ff:ff:ff:ff:ff:ff
#> 3: docker0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc noqueue state DOWN mode DEFAULT group default
#> link/ether 02:42:aa:c0:e3:ed brd ff:ff:ff:ff:ff:ff
#> 4: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state DOWN mode DEFAULT group default
#> link/ether 02:42:aa:c0:e3:ed brd ff:ff:ff:ff:ff:ff
If the switch creates a network with CIDRCIDR
CIDR (Classless Inter-Domain Routing) notation can be used to represent a range of IP addresses. It has two parts:
prefix - Network address (a normal IP address)
suffix - number of bits of the... 192.168.1.0/24, we can use the interface to assign the addresses to the machines on this network:
ip addr add 192.168.1.10/24 dev eth0
This command will assign ip adress 192.168.1.10 and subnet mask 255.255.255.0 to the interface eth0. However, this change will be lost with restart. To persist it, you need to make a change in /etc/network/interfaces file.
The switch can only send/receive packets from/to the systems within its network. If we have another network, in order for host from network 1 to reach the host on network 2, we will need a Network RouterNetwork Router
A router helps connect two networks together. It can be thought of as another host with many network ports. Since it connects to two networks, it will be assigned two IPs - one on each network.
In....
Status: #💡