peter/infix
1
0
Fork 0
mirror of https://github.com/kernelkit/infix.git synced 2026-07-30 04:33:00 +02:00
Code Issues Packages Projects Releases Wiki Activity
Files
72dc0f87f5ff561f09f0be61ba2b6cf01ef6b6bc
infix/doc/networking.md
T
Mattias WalströmandJoachim Wiberg 20cc36864a OSPF: Enable BFD integration 
admin@example:/config/> edit routing control-plane-protocol ietf-ospf:ospfv2 name default
    admin@example:/config/routing/control-plane-protocol/ietf-ospf:ospfv2/name/default/ospf/> set area 0.0.0.0 interface e0 bfd enabled true
    admin@example:/config/routing/control-plane-protocol/static/name/default/> leave
    admin@example:/>
2024-01-08 10:04:44 +01:00

502 lines
26 KiB
Markdown
Raw Blame History

# Linux Networking
## Interface LEGO®
![Linux Networking Blocks](img/lego.svg)
| **Type** | **Yang Model** | **Description** |
| -------- | ----------------- | ------------------------------------------------------------- |
| bridge | infix-if-bridge | SW implementation of an IEEE 802.1Q bridge |
| ip | ietf-ip, infix-ip | IP address to the subordinate interface |
| vlan | infix-if-vlan | Capture all traffic belonging to a specific 802.1Q VID |
| lag[^1] | infix-if-lag | Bonds multiple interfaces into one, creating a link aggregate |
| lo | ietf-interfaces | Software loopback interface |
| eth | ietf-interfaces | Physical Ethernet device/port |
| veth | infix-if-veth | Virtual Ethernet pair, typically one end is in a container |
## Data Plane
The blocks you ctose, and how you connect them, defines your data plane. Here we see an example of how to bridge a virtual port with a physical LAN.
![Example of a 4-port switch with a link aggregate and a VETH pair to a container](img/dataplane.svg)
Depending on the (optional) VLAN filtering of the bridge, the container may have full or limited connectivity with outside ports, as well as the internal CPU.
In fact the virtual port connected to the bridge can be member of several VLANs, with each VLAN being an interface with an IP address inside the container.
Thanks to Linux, and technologies like switchdev, that allow you to split a switching fabric into unique (isolated) ports, the full separation and virtualization of all Ethernet layer properties are possible to share with a container. Meaning, all the building blocks used on the left hand side can also be used freely on the right hand side as well.
### Bridging
This is the most central part of the system. A bridge is a switch, and a switch is a bridge. In Linux, setting up a bridge with ports connected to physical switch fabric, means you manage the actual switch fabric!
In Infix ports are by default not switch ports, unless the customer specific factory config sets it up this way. To enable switching between ports you create a bridge and then add ports to that bridge. That's it.
```
admin@example:/> configure
admin@example:/config/> edit interface br0
admin@example:/config/interface/br0/> up
admin@example:/config/> set interface eth0 bridge-port bridge br0
admin@example:/config/> set interface eth1 bridge-port bridge br0
admin@example:/config/> leave
```
Here we add two ports to bridge `br0`: `eth0` and `eth1`.
> **Note:** Infix has many built-in helpers controlled by convention. E.g., if you name your bridge `brN`, where `N` is a number, Infix will set the interface type automatically for you, and unlock all bridge features for you.
#### VLAN Filtering Bridge
By default bridges in Linux do not filter based on VLAN tags. It can be enabled in Infix when creating a bridge by adding a port to a VLAN as a tagged or untagged member.
Use the port default VID (PVID) setting to control VLAN association for traffic ingressing a port untagged (default PVID: 1).
```
admin@example:/config/> edit interface br0
admin@example:/config/interface/br0/> up
admin@example:/config/> set interface eth0 bridge-port bridge br0
admin@example:/config/> set interface eth0 bridge-port pvid 10
admin@example:/config interface eth1 bridge-port bridge br0
admin@example:/config/> set interface eth1 bridge-port pvid 20
admin@example:/config/> edit interface br0
admin@example:/config/interface/br0/> set bridge vlans vlan 10 untagged eth0
admin@example:/config/interface/br0/> set bridge vlans vlan 20 untagged eth1
```
This sets `eth0` as an untagged member of VLAN 10 and `eth1` as an
untagged member of VLAN 20. Switching between these ports is thus
prohibited.
To terminate a VLAN in the switch itself, either for switch management or for routing, the bridge must become a (tagged) member of the VLAN.
```
admin@example:/config/interface/br0/> set bridge vlans vlan 10 tagged br0
admin@example:/config/interface/br0/> set bridge vlans vlan 20 tagged br0
```
> To route or to manage via a VLAN, a VLAN interface also needs to be created on top of the bridge, see section [VLAN Interfaces](#vlan-interfaces) below.
### VLAN Interfaces
Creating a VLAN can be done in many ways. This section assumes VLAN interfaces created atop another Linux interface. E.g., the VLAN interfaces created on top of the Ethernet interface or bridge in the picture below.
![VLAN interface on top of Ethernet or Bridge interfaces](img/interface-vlan-variants.svg)
A VLAN interface is basically a filtering abstraction. When you run `tcpdump` on a VLAN interface you will only see the frames matching the VLAN ID of the interface, compared to *all* the VLAN IDs if you run `tcpdump` on the lower-layer interface.
```
admin@example:/> configure
admin@example:/config/> edit interface eth0.20
admin@example:/config/interface/eth0.20/> set vlan id 20
admin@example:/config/interface/eth0.20/> set vlan lower-layer-if eth0
admin@example:/config/interface/eth0.20/> leave
```
The example below assumes bridge br0 is already created, see [VLAN Filtering Bridge](#vlan-filtering-bridge).
```
admin@example:/> configure
admin@example:/config/> edit interface vlan10
admin@example:/config/interface/vlan10/> set vlan id 10
admin@example:/config/interface/vlan10/> set vlan lower-layer-if br0
admin@example:/config/interface/vlan10/> leave
```
As conventions, a VLAN interface for VID 20 on top of an Ethernet interface *eth0* is named *eth0.20*, and a VLAN interface for VID 10 on top of a bridge interface *br0* is named *vlan10*.
> **Note:** If you name your VLAN interface `foo0.N` or `vlanN`, where `N` is a number, Infix will set the interface type automatically for you.
## Management Plane
This section details IP Addresses And Other Per-Interface IP settings.
Infix support several network interface types, each can be assigned one or more IP addresses, both IPv4 and IPv6 are supported.
![IP on top of network interface examples](img/ip-iface-examples.svg)
### IPv4 Address Assignment
Multiple address assignment methods are available:
| **Type** | **Yang Model** | **Description** |
|:---------- |:----------------- |:-------------------------------------------------------------- |
| static | ietf-ip | Static assignment of IPv4 address, e.g., *10.0.1.1/24* |
| link-local | infix-ip | Auto-assignment of IPv4 address in 169.254.x.x/16 range |
| dhcp | infix-dhcp-client | Assignment of IPv4 address by DHCP server, e.g., *10.0.1.1/24* |
Supported DHCP (request) options, configurability (Cfg) and defaults,
are listed below. Configurable options can be disabled on a per client
interface basis, some options, like `clientid` and option 81, are
possible to set the value of as well.
| **Opt** | **Name** | **Cfg** | **Description** |
|---------|------------------|---------|-----------------------------------------------------|
| 1 | `subnet` | No | Request IP address and netmask |
| 3 | `router` | Yes | Default route(s), see also option 121 and 249 |
| 6 | `dns` | Yes | DNS server(s), static ones take precedence |
| 12 | `hostname` | Yes | DHCP cannot set hostname, only for informing server |
| 15 | `domain` | Yes | Default domain name, for name resolution |
| 28 | `broadcast` | Yes | Broadcast address, calculated if disabled |
| 42 | `ntpsrv` | Yes | NTP server(s), static ones take precedence |
| 50 | `address` | Yes | Request (previously cached) address |
| 61 | `clientid` | Yes | Default MAC address (and option 12) |
| 81 | `fqdn` | Yes | Similar to option 12, request FQDN update in DNS |
| 119 | `search` | Yes | Request domain search list |
| 121 | `staticroutes` | Yes | Classless static routes |
| 249 | `msstaticroutes` | Yes | Microsoft static route |
| | | | |
**Default:** `router`, `dns`, `domain`, `broadcast`, `ntpsrv`, `search`,
`address`, `staticroutes`, `msstaticroutes`
> **Note:** DHCP address method is only available for *LAN* interfaces
> (Ethernet, virtual Ethernet (veth), bridge, link aggregates, etc.)
### IPv6 Address Assignment
Multiple address assignment methods are available:
| **Type** | **Yang Model** | **Description** |
|:---------------- |:-------------- |:------------------------------------------------------------------------------------------------------------------------------------------------- |
| static | ietf-ip | Static assignment of IPv6 address, e.g., *2001:db8:0:1::1/64* |
| link-local | ietf-ip[^2] | (RFC4862) Auto-configured link-local IPv6 address (*fe80::0* prefix + interface identifier, e.g., *fe80::ccd2:82ff:fe52:728b/64*) |
| global auto-conf | ietf-ip | (RFC4862) Auto-configured (stateless) global IPv6 address (prefix from router + interface identifier, e.g., *2001:db8:0:1:ccd2:82ff:fe52:728b/64* |
Both for *link-local* and *global auto-configuration*, it is possible
to auto-configure using a random suffix instead of the interface
identifier.
### Examples
![Switch example (eth0 and lo)](img/ip-address-example-switch.svg)
admin@example:/> show interfaces
INTERFACE PROTOCOL STATE DATA
eth0 ethernet UP 02:00:00:00:00:00
ipv6 fe80::ff:fe00:0/64 (link-layer)
lo ethernet UP 00:00:00:00:00:00
ipv4 127.0.0.1/8 (static)
ipv6 ::1/128 (static)
admin@example:/>
To illustrate IP address configuration, the examples below uses a
switch with a single Ethernet interface (eth0) and a loopback
interface (lo). As shown above, these examples assume *eth0* has an
IPv6 link-local address and *lo* has static IPv4 and IPv6 addresses by
default.
#### Static and link-local IPv4 addresses
![Setting static IPv4 (and link-local IPv4)](img/ip-address-example-ipv4-static.svg)
admin@example:/> configure
admin@example:/config/> edit interface eth0 ipv4
admin@example:/config/interface/eth0/ipv4/> set address 10.0.1.1 prefix-length 24
admin@example:/config/interface/eth0/ipv4/> set autoconf enabled true
admin@example:/config/interface/eth0/ipv4/> diff
+interfaces {
+ interface eth0 {
+ ipv4 {
+ address 10.0.1.1 {
+ prefix-length 24;
+ }
+ autoconf {
+ enabled true;
+ }
+ }
+ }
+}
admin@example:/config/interface/eth0/ipv4/> leave
admin@example:/> show interfaces
INTERFACE PROTOCOL STATE DATA
eth0 ethernet UP 02:00:00:00:00:00
ipv4 169.254.1.3/16 (random)
ipv4 10.0.1.1/24 (static)
ipv6 fe80::ff:fe00:0/64 (link-layer)
lo ethernet UP 00:00:00:00:00:00
ipv4 127.0.0.1/8 (static)
ipv6 ::1/128 (static)
admin@example:/>
As shown, the link-local IPv4 address is configured with `set autconf
enabled true`. The resulting address (169.254.1.3/16) is of type
*random* ([IETF ip-yang][ietf-ip-yang]).
#### Use of DHCP for IPv4 address assignment
![Using DHCP for IPv4 address assignment](img/ip-address-example-ipv4-dhcp.svg)
admin@example:/> configure
admin@example:/config/> edit dhcp-client
admin@example:/config/dhcp-client/> set client-if eth0
admin@example:/config/dhcp-client/> set enabled true
admin@example:/config/dhcp-client/> leave
admin@example:/> show interfaces
INTERFACE PROTOCOL STATE DATA
eth0 ethernet UP 02:00:00:00:00:00
ipv4 10.1.2.100/24 (dhcp)
ipv6 fe80::ff:fe00:0/64 (link-layer)
lo ethernet UP 00:00:00:00:00:00
ipv4 127.0.0.1/8 (static)
ipv6 ::1/128 (static)
admin@example:/>
The resulting address (10.1.2.100/24) is of type *dhcp*.
#### Disabling IPv6 link-local address(es)
The (only) way to disable IPv6 link-local addresses is by disabling IPv6 on the interface.
```(disabling
admin@example:/> configure
admin@example:/config/> edit interface eth0 ipv6
admin@example:/config/interface/eth0/ipv6/> set enabled false
admin@example:/config/interface/eth0/ipv6/> leave
admin@example:/> show interfaces
INTERFACE PROTOCOL STATE DATA
eth0 ethernet UP 02:00:00:00:00:00
lo ethernet UP 00:00:00:00:00:00
ipv4 127.0.0.1/8 (static)
ipv6 ::1/128 (static)
admin@example:/>
```
#### Static IPv6 address
![Setting static IPv6](img/ip-address-example-ipv6-static.svg)
admin@example:/> configure
admin@example:/config/> edit interface eth0 ipv6
admin@example:/config/interface/eth0/ipv6/> set address 2001:db8::1 prefix-length 64
admin@example:/config/interface/eth0/ipv6/> leave
admin@example:/> show interfaces
INTERFACE PROTOCOL STATE DATA
eth0 ethernet UP 02:00:00:00:00:00
ipv6 2001:db8::1/64 (static)
ipv6 fe80::ff:fe00:0/64 (link-layer)
lo ethernet UP 00:00:00:00:00:00
ipv4 127.0.0.1/8 (static)
ipv6 ::1/128 (static)
admin@example:/>
#### Stateless Auto-configuration of Global IPv6 Address
![Auto-configuration of global IPv6](img/ip-address-example-ipv6-auto-global.svg)
Stateless address auto-configuration of global addresses is enabled by
default. The address is formed by concatenating the network prefix
advertised by the router (here 2001:db8:0:1::0/64) and the interface
identifier. The resulting address is of type *link-layer*, as it
is formed based on the interface identifier ([IETF
ip-yang][ietf-ip-yang]).
admin@example:/> show interfaces
INTERFACE PROTOCOL STATE DATA
eth0 ethernet UP 02:00:00:00:00:00
ipv6 2001:db8:0:1:0:ff:fe00:0/64 (link-layer)
ipv6 fe80::ff:fe00:0/64 (link-layer)
lo ethernet UP 00:00:00:00:00:00
ipv4 127.0.0.1/8 (static)
ipv6 ::1/128 (static)
admin@example:/>
Disabling auto-configuration of global IPv6 addresses can be done as shown
below.
admin@example:/> configure
admin@example:/config/> edit interface eth0 ipv6
admin@example:/config/interface/eth0/ipv6/> set autoconf create-global-addresses false
admin@example:/config/interface/eth0/ipv6/> leave
admin@example:/> show interfaces
INTERFACE PROTOCOL STATE DATA
eth0 ethernet UP 02:00:00:00:00:00
ipv6 fe80::ff:fe00:0/64 (link-layer)
lo ethernet UP 00:00:00:00:00:00
ipv4 127.0.0.1/8 (static)
ipv6 ::1/128 (static)
admin@example:/>
#### Random Link Identifiers for IPv6 Stateless Autoconfiguration
![Auto-configuration of global IPv6](img/ip-address-example-ipv6-auto-global.svg)
By default, the auto-configured link-local and global IPv6 addresses
are formed from a link-identifier based on the MAC address.
admin@example:/> show interfaces
INTERFACE PROTOCOL STATE DATA
eth0 ethernet UP 02:00:00:00:00:00
ipv6 2001:db8:0:1:0:ff:fe00:0/64 (link-layer)
ipv6 fe80::ff:fe00:0/64 (link-layer)
lo ethernet UP 00:00:00:00:00:00
ipv4 127.0.0.1/8 (static)
ipv6 ::1/128 (static)
admin@example:/>
To avoid revealing identity information in the IPv6 address, it is
possible to specify use of a random identifier ([ietf-ip][ietf-ip-yang] YANG and [RFC8981][ietf-ipv6-privacy]).
admin@example:/> configure
admin@example:/config/> edit interface eth0 ipv6
admin@example:/config/interface/eth0/ipv6/> set autoconf create-temporary-addresses true
admin@example:/config/interface/eth0/ipv6/> leave
admin@example:/> show interfaces
INTERFACE PROTOCOL STATE DATA
eth0 ethernet UP 02:00:00:00:00:00
ipv6 2001:db8:0:1:b705:8374:638e:74a8/64 (random)
ipv6 fe80::ad3d:b274:885a:9ffb/64 (random)
lo ethernet UP 00:00:00:00:00:00
ipv4 127.0.0.1/8 (static)
ipv6 ::1/128 (static)
admin@example:/>
Both the link-local address (fe80::) and the global address (2001:)
have changed type to *random*.
### IPv4 forwarding
To be able to route (static or dynamic) on the interface it is
required to enable forwarding. This setting controlls if packets
received on this interface can be forwarded.
```
admin@example:/config/> edit interface eth0
admin@example:/config/interface/eth0/> set ipv4 forwarding
admin@example:/config/interface/eth0/> leave
admin@example:/>
```
### IPv6 forwarding
This flag behaves totally different than for IPv4. For IPv6 the
ability to route between interfaces is always enabled, instead this
flag controls if the interface will be in host/router mode.
| **Feature** | **Forward enabled** | **Forward disabled** |
|:------------------------------------------|:--------------------|:---------------------|
| IsRouter set in Neighbour Advertisements. | Yes | No |
| Transmit Router Solicitations. | No | Yes |
| Router Advertisements are ignored | No | Yes |
| Accept Redirects | No | Yes |
```
admin@example:/config/> edit interface eth0
admin@example:/config/interface/eth0/> set ipv6 forwarding
admin@example:/config/interface/eth0/> leave
admin@example:/>
```
## Routing support
| **Yang Model** | **Description** |
|:--------------------------|:--------------------------------------------------------------------------------------|
| ietf-routing | Base model, used to set configuration and read operational status in the other models |
| ietf-ipv4-unicast-routing | Static IPv4 unicast routing |
| ietf-ipv6-unicast-routing | Static IPv6 unicast routing |
| ietf-ospf | OSPF routing |
| infix-routing | Infix deviations |
### IPv4 Static routes
Remember to enable [IPv4 forwarding](#IPv4-forwarding) for the interfaces.
admin@example:/> configure
admin@example:/config/> edit routing control-plane-protocol static name default
admin@example:/config/routing/control-plane-protocol/static/name/default/> set ipv4 route 192.168.200.0/24 next-hop next-hop-address 192.168.1.1
admin@example:/config/routing/control-plane-protocol/static/name/default/> leave
admin@example:/>
> **Note:** The only name allowed for a control-plane-protocol is currently
> *default*. Meaning, you can only have one instance per routing protocol.
### IPv6 Static routes
admin@example:/> configure
admin@example:/config/> edit routing control-plane-protocol static name default
admin@example:/config/routing/control-plane-protocol/static/name/default/> set ipv6 route 2001:db8:3c4d:200::/64 next-hop next-hop-address 2001:db8:3c4d:1::1
admin@example:/config/routing/control-plane-protocol/static/name/default/> leave
admin@example:/>
> **Note:** The only name allowed for a control-plane-protocol is currently
> *default*. Meaning, you can only have one instance per routing protocol.
#### OSPFv2 Routing
Remember to enable [IPv4 forwarding](#IPv4-forwarding) for the
interfaces you want to run OSPFv2.
admin@example:/config/> edit routing control-plane-protocol ietf-ospf:ospfv2 name default
admin@example:/config/routing/control-plane-protocol/ietf-ospf:ospfv2/name/default/> set ospf area 0.0.0.0 interface e0 enabled true
admin@example:/config/routing/control-plane-protocol/static/name/default/> leave
admin@example:/>
> **Note:** The only name allowed for a control-plane-protocol is currently
> *default*. Meaning, you can only have one instance per routing protocol.
### Stub area types
NSSA and Stub areas are currently supported.
To configure a NSSA area with summary routes:
admin@example:/config/> edit routing control-plane-protocol ietf-ospf:ospfv2 name default
admin@example:/config/routing/control-plane-protocol/ietf-ospf:ospfv2/name/default/> set ospf area 0.0.0.1 area-type nssa-area
admin@example:/config/routing/control-plane-protocol/ietf-ospf:ospfv2/name/default/> set ospf area 0.0.0.1 summary true
admin@example:/config/routing/control-plane-protocol/static/name/default/> leave
admin@example:/>
### Bidirectional Forwarding Detection (BFD)
It is possible to enable BFD per interface to speed up detection of
link loss.
admin@example:/config/> edit routing control-plane-protocol ietf-ospf:ospfv2 name default
admin@example:/config/routing/control-plane-protocol/ietf-ospf:ospfv2/name/default/ospf/> set area 0.0.0.0 interface e0 bfd enabled true
admin@example:/config/routing/control-plane-protocol/static/name/default/> leave
admin@example:/>
### Debug OSPFv2
Using NETCONF and the YANG model *ietf-routing* it is possible to read the OSPF routing table, neighbors
and more, that may be useful for debugging the OSPFv2 setup.
### View routing table
The routing table can be viewed from the operational datastore over
NETCONF or using the CLI:
#### IPv4 routing table
admin@example:/> show routes ipv4
PREFIX NEXT-HOP PREF PROTOCOL
192.168.1.0/24 e0 kernel
192.168.200.0/24 192.168.1.1 20 static
admin@example:/>
#### IPv6 routing table
admin@example:/> show routes ipv6
PREFIX NEXT-HOP PREF PROTOCOL
2001:db8:3c4d:50::/64 eth4 256 kernel
fe80::/64 eth5 256 kernel
fe80::/64 eth3 256 kernel
fe80::/64 eth1 256 kernel
fe80::/64 eth0 256 kernel
fe80::/64 eth2 256 kernel
fe80::/64 eth4 256 kernel
admin@example:/>
#### Source protocol
The source protocol describes the origin of the route.
| **Protocol** | **Description** |
|:-------------|:---------------------------------------------------------------------|
| kernel | Added when setting a subnet address on an interface |
| static | User created static routes |
| dhcp | Routes retrieved from DHCP |
The YANG model *ietf-routing* support multiple ribs but only two are
currently supported, namely `ipv4` and `ipv6`.
[ietf-ip-yang]: https://www.rfc-editor.org/rfc/rfc8344.html
[ietf-ipv6-privacy]: https://www.rfc-editor.org/rfc/rfc8981.html
[^1]: Please note, link aggregates are not yet supported in Infix.
[^2]: Link-local IPv6 addresses are implicitly enabled when enabling IPv6.
IPv6 can be enabled/disabled per interface in the [ietf-ip][ietf-ip-yang]
YANG model.
Reference in New Issue View Git Blame Copy Permalink