[Notes] Network Planning and Administration: Physical Transmission Media
Physical means of data transmission.
VMware Workstation
- Virtual machines in .ova file are imported (simply opening them in File -> Open…). To open a virtual machine without importing it: Open .vmx file.
- For NAT, the virtual switch is VMnet8 (only one NAT, there cannot be two). The host IP is 192.168.241.1 and the gateway is 192.168.241.2.
- In bridged, the virtual switch is VMnet0, the IPs assigned to the virtual machines are from the network of the host machine.
- In host-only, the virtual switch is VMnet1, there is no gateway so there will be no access to the internet although the machines will see each other (network 192.168.58.0) .
- Custom by default will be VMnet* and type host-only. But by disabling DHCP and disconnecting it from the host (in the adapter properties in VMware) it becomes LAN Segment.
- LAN Segment does not have DHCP and does not include the host.
Commands
- arp -a (on win and gnu/linux to see ip, mac, network adapter open connections)
- ipconfig /all (win only, to see all network adapters)
- ifconfig -a (gnu/linux only, to see all network adapters)
- route -n (in gnu/linux to see gateway)
- tracert (win) traceroute (gnu/linux)
In general, on GNU/Linux distributions, arp, ifconfig, and route are in the net-tools package. Traceroute usually has its own traceroute package.
Subnet Calculator
subnettingpractice.com/vlsm.html
Configure network in GNU/Linux
# nano /etc/network/interfaces
Where says
auto ens33
iface ens33 inet dhcp
Should say
auto ens33
iface ens33 inet static
address 172.16.0.99
netmask 255.255.255.0
gateway 172.16.0.254
dns-nameservers 1.1.1.1 8.8.8.8
# shutdown -r now
⚠️ For Ubuntu 18, see how to configure netplan .
Configure GNU/Linux as a router (forwarder)
Requires two network adapters. In this example, ens33 (bridged in VMware) will be the external network adapter, ens37 (LAN Segment in VMware) the internal network adapter (ifconfig -a to see all network adapters):
# nano /etc/network/interfaces
Where says
auto ens33
iface ens33 inet static
address 172.16.0.99
netmask 255.255.255.0
gateway 172.16.0.254
dns-nameservers 1.1.1.1 8.8.8.8
Should say
auto ens33
iface ens33 inet static
address 172.16.0.99
netmask 255.255.255.0
gateway 172.16.0.254
dns-nameservers 1.1.1.1 8.8.8.8
auto ens37
iface ens37 inet static
address 172.16.99.254
netmask 255.255.255.0
⚠️ For Ubuntu 18, see how to configure netplan .
# shutdown -r now
# nano /etc/sysctl.conf
Where says
#net.ipv4.ip_forward=1
Should say
net.ipv4.ip_forward=1
# Disable IPv6:
#net.ipv6.conf.all.disable_ipv6=1
# sysctl -p