Configuring the network: an address that survives a reboot
Assigning what the earlier courses taught you to read: addresses, routes, MTU, bridges, bonds and translation rules — and making them persist.
`ip addr add` repairs a machine until it next reboots. The file that decides at boot has not been touched. This course teaches both layers — the kernel's live state and the declared configuration Netplan renders — and then everything configured on top of them: static routes, the MTU, bridges, bonds, VLANs, address translation and port forwarding. Its last chapter crosses the one-machine boundary, and says so.
What you will be able to do
- Tell what `ip` changes now from what Netplan decides at boot, and write the second
- Assign a complete static address — prefix, default route, resolvers — without reaching for `gateway4`
- Add a static route, confirm with ip route get that it is the one chosen, and make it persist
- Build a bridge, a bond and a VLAN interface, and read what each one reports
- Write a port-forwarding rule and a masquerade rule, and read them back in the ruleset
Before this course
Taken from the learning path this course belongs to: the course placed just before it. A suggested order, not a lock — nothing here closes until you have finished it.
Outline
- 01
Addresses you assign
Two layers — live state and the file that decides — then the address, the routes and the MTU written for good.
- 02
The link layer you build
A switch in software, two cards acting as one, and a tag that separates two networks on one cable.
- 03
Past one machine
Rewriting addresses in flight, spreading across two servers, floating an address, and agreeing on the time.
Technical content last reviewed on 21 September 2026