X-Git-Url: https://git.proxmox.com/?p=pve-docs.git;a=blobdiff_plain;f=pve-network.adoc;h=b2dae9780247339bbdfdda13deb7fd2bd2d861a5;hp=45f64249b687c52c6d52a3145aab8b602f3159a1;hb=dd1aa0e01624f5927fb65143c9a070672ccbeb92;hpb=e60ce90c622dcc96f6f86229a9f0a3caa9a8f60f diff --git a/pve-network.adoc b/pve-network.adoc index 45f6424..b2dae97 100644 --- a/pve-network.adoc +++ b/pve-network.adoc @@ -5,71 +5,124 @@ ifdef::wiki[] :pve-toplevel: endif::wiki[] -{pve} uses a bridged networking model. Each host can have up to 4094 -bridges. Bridges are like physical network switches implemented in -software. All VMs can share a single bridge, as if -virtual network cables from each guest were all plugged into the same -switch. But you can also create multiple bridges to separate network -domains. - -For connecting VMs to the outside world, bridges are attached to -physical network cards. For further flexibility, you can configure -VLANs (IEEE 802.1q) and network bonding, also known as "link -aggregation". That way it is possible to build complex and flexible -virtual networks. +Network configuration can be done either via the GUI, or by manually +editing the file `/etc/network/interfaces`, which contains the +whole network configuration. The `interfaces(5)` manual page contains the +complete format description. All {pve} tools try hard to keep direct + user modifications, but using the GUI is still preferable, because it +protects you from errors. -Debian traditionally uses the `ifup` and `ifdown` commands to -configure the network. The file `/etc/network/interfaces` contains the -whole network setup. Please refer to to manual page (`man interfaces`) -for a complete format description. +Once the network is configured, you can use the Debian traditional tools `ifup` +and `ifdown` commands to bring interfaces up and down. NOTE: {pve} does not write changes directly to `/etc/network/interfaces`. Instead, we write into a temporary file called `/etc/network/interfaces.new`, and commit those changes when you reboot the node. -It is worth mentioning that you can directly edit the configuration -file. All {pve} tools tries hard to keep such direct user -modifications. Using the GUI is still preferable, because it -protect you from errors. - - Naming Conventions ~~~~~~~~~~~~~~~~~~ We currently use the following naming conventions for device names: -* Ethernet devices: eth[N], where 0 ≤ N (`eth0`, `eth1`, ...) +* Ethernet devices: en*, systemd network interface names. This naming scheme is + used for new {pve} installations since version 5.0. + +* Ethernet devices: eth[N], where 0 ≤ N (`eth0`, `eth1`, ...) This naming +scheme is used for {pve} hosts which were installed before the 5.0 +release. When upgrading to 5.0, the names are kept as-is. * Bridge names: vmbr[N], where 0 ≤ N ≤ 4094 (`vmbr0` - `vmbr4094`) * Bonds: bond[N], where 0 ≤ N (`bond0`, `bond1`, ...) * VLANs: Simply add the VLAN number to the device name, - separated by a period (`eth0.50`, `bond1.30`) + separated by a period (`eno1.50`, `bond1.30`) This makes it easier to debug networks problems, because the device -names implies the device type. +name implies the device type. + +Systemd Network Interface Names +^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +Systemd uses the two character prefix 'en' for Ethernet network +devices. The next characters depends on the device driver and the fact +which schema matches first. + +* o[n|d] — devices on board + +* s[f][n|d] — device by hotplug id + +* [P]ps[f][n|d] — devices by bus id + +* x — device by MAC address + +The most common patterns are: + +* eno1 — is the first on board NIC + +* enp3s0f1 — is the NIC on pcibus 3 slot 0 and use the NIC function 1. + +For more information see https://www.freedesktop.org/wiki/Software/systemd/PredictableNetworkInterfaceNames/[Predictable Network Interface Names]. + +Choosing a network configuration +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +Depending on your current network organization and your resources you can +choose either a bridged, routed, or masquerading networking setup. + +{pve} server in a private LAN, using an external gateway to reach the internet +^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +The *Bridged* model makes the most sense in this case, and this is also +the default mode on new {pve} installations. +Each of your Guest system will have a virtual interface attached to the +{pve} bridge. This is similar in effect to having the Guest network card +directly connected to a new switch on your LAN, the {pve} host playing the role +of the switch. + +{pve} server at hosting provider, with public IP ranges for Guests +^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +For this setup, you can use either a *Bridged* or *Routed* model, depending on +what your provider allows. + +{pve} server at hosting provider, with a single public IP address +^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ + +In that case the only way to get outgoing network accesses for your guest +systems is to use *Masquerading*. For incoming network access to your guests, +you will need to configure *Port Forwarding*. + +For further flexibility, you can configure +VLANs (IEEE 802.1q) and network bonding, also known as "link +aggregation". That way it is possible to build complex and flexible +virtual networks. Default Configuration using a Bridge ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +[thumbnail="default-network-setup-bridge.svg"] +Bridges are like physical network switches implemented in software. +All VMs can share a single bridge, or you can create multiple bridges to +separate network domains. Each host can have up to 4094 bridges. + The installation program creates a single bridge named `vmbr0`, which -is connected to the first ethernet card `eth0`. The corresponding -configuration in `/etc/network/interfaces` looks like this: +is connected to the first Ethernet card. The corresponding +configuration in `/etc/network/interfaces` might look like this: ---- auto lo iface lo inet loopback -iface eth0 inet manual +iface eno1 inet manual auto vmbr0 iface vmbr0 inet static address 192.168.10.2 netmask 255.255.255.0 gateway 192.168.10.1 - bridge_ports eth0 + bridge_ports eno1 bridge_stp off bridge_fd 0 ---- @@ -79,7 +132,6 @@ physical network. The network, in turn, sees each virtual machine as having its own MAC, even though there is only one network cable connecting all of these VMs to the network. - Routed Configuration ~~~~~~~~~~~~~~~~~~~~ @@ -87,7 +139,7 @@ Most hosting providers do not support the above setup. For security reasons, they disable networking as soon as they detect multiple MAC addresses on a single interface. -TIP: Some providers allows you to register additional MACs on there +TIP: Some providers allows you to register additional MACs on their management interface. This avoids the problem, but is clumsy to configure because you need to register a MAC for each of your VMs. @@ -95,27 +147,29 @@ You can avoid the problem by ``routing'' all traffic via a single interface. This makes sure that all network packets use the same MAC address. -A common scenario is that you have a public IP (assume `192.168.10.2` +[thumbnail="default-network-setup-routed.svg"] +A common scenario is that you have a public IP (assume `198.51.100.5` for this example), and an additional IP block for your VMs -(`10.10.10.1/255.255.255.0`). We recommend the following setup for such +(`203.0.113.16/29`). We recommend the following setup for such situations: ---- auto lo iface lo inet loopback -auto eth0 -iface eth0 inet static - address 192.168.10.2 +auto eno1 +iface eno1 inet static + address 198.51.100.5 netmask 255.255.255.0 - gateway 192.168.10.1 - post-up echo 1 > /proc/sys/net/ipv4/conf/eth0/proxy_arp + gateway 198.51.100.1 + post-up echo 1 > /proc/sys/net/ipv4/ip_forward + post-up echo 1 > /proc/sys/net/ipv4/conf/eno1/proxy_arp auto vmbr0 iface vmbr0 inet static - address 10.10.10.1 - netmask 255.255.255.0 + address 203.0.113.17 + netmask 255.255.255.248 bridge_ports none bridge_stp off bridge_fd 0 @@ -125,19 +179,21 @@ iface vmbr0 inet static Masquerading (NAT) with `iptables` ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ -In some cases you may want to use private IPs behind your Proxmox -host's true IP, and masquerade the traffic using NAT: +Masquerading allows guests having only a private IP address to access the +network by using the host IP address for outgoing traffic. Each outgoing +packet is rewritten by `iptables` to appear as originating from the host, +and responses are rewritten accordingly to be routed to the original sender. ---- auto lo iface lo inet loopback -auto eth0 -#real IP adress -iface eth0 inet static - address 192.168.10.2 +auto eno1 +#real IP address +iface eno1 inet static + address 198.51.100.5 netmask 255.255.255.0 - gateway 192.168.10.1 + gateway 198.51.100.1 auto vmbr0 #private sub network @@ -149,8 +205,8 @@ iface vmbr0 inet static bridge_fd 0 post-up echo 1 > /proc/sys/net/ipv4/ip_forward - post-up iptables -t nat -A POSTROUTING -s '10.10.10.0/24' -o eth0 -j MASQUERADE - post-down iptables -t nat -D POSTROUTING -s '10.10.10.0/24' -o eth0 -j MASQUERADE + post-up iptables -t nat -A POSTROUTING -s '10.10.10.0/24' -o eno1 -j MASQUERADE + post-down iptables -t nat -D POSTROUTING -s '10.10.10.0/24' -o eno1 -j MASQUERADE ---- @@ -218,8 +274,13 @@ slaves in the single logical bonded interface such that different network-peers use different MAC addresses for their network packet traffic. -For the most setups the active-backup are the best choice or if your -switch support LACP "IEEE 802.3ad" this mode should be preferred. +If your switch support the LACP (IEEE 802.3ad) protocol then we recommend using +the corresponding bonding mode (802.3ad). Otherwise you should generally use the +active-backup mode. + +// http://lists.linux-ha.org/pipermail/linux-ha/2013-January/046295.html +If you intend to run your cluster network on the bonding interfaces, then you +have to use active-passive mode on the bonding interfaces, other modes are +unsupported. The following bond configuration can be used as distributed/shared storage network. The benefit would be that you get more speed and the @@ -230,13 +291,13 @@ network will be fault-tolerant. auto lo iface lo inet loopback -iface eth1 inet manual +iface eno1 inet manual -iface eth2 inet manual +iface eno2 inet manual auto bond0 iface bond0 inet static - slaves eth1 eth2 + slaves eno1 eno2 address 192.168.1.2 netmask 255.255.255.0 bond_miimon 100 @@ -247,14 +308,15 @@ auto vmbr0 iface vmbr0 inet static address 10.10.10.2 netmask 255.255.255.0 - gateway 10.10.10.1 - bridge_ports eth0 + gateway 10.10.10.1 + bridge_ports eno1 bridge_stp off bridge_fd 0 ---- +[thumbnail="default-network-setup-bond.svg"] Another possibility it to use the bond directly as bridge port. This can be used to make the guest network fault-tolerant. @@ -263,13 +325,13 @@ This can be used to make the guest network fault-tolerant. auto lo iface lo inet loopback -iface eth1 inet manual +iface eno1 inet manual -iface eth2 inet manual +iface eno2 inet manual auto bond0 -iface bond0 inet maunal - slaves eth1 eth2 +iface bond0 inet manual + slaves eno1 eno2 bond_miimon 100 bond_mode 802.3ad bond_xmit_hash_policy layer2+3 @@ -278,7 +340,149 @@ auto vmbr0 iface vmbr0 inet static address 10.10.10.2 netmask 255.255.255.0 - gateway 10.10.10.1 + gateway 10.10.10.1 + bridge_ports bond0 + bridge_stp off + bridge_fd 0 + +---- + + +VLAN 802.1Q +~~~~~~~~~~~ + +A virtual LAN (VLAN) is a broadcast domain that is partitioned and +isolated in the network at layer two. So it is possible to have +multiple networks (4096) in a physical network, each independent of +the other ones. + +Each VLAN network is identified by a number often called 'tag'. +Network packages are then 'tagged' to identify which virtual network +they belong to. + + +VLAN for Guest Networks +^^^^^^^^^^^^^^^^^^^^^^^ + +{pve} supports this setup out of the box. You can specify the VLAN tag +when you create a VM. The VLAN tag is part of the guest network +configuration. The networking layer supports different modes to +implement VLANs, depending on the bridge configuration: + +* *VLAN awareness on the Linux bridge:* +In this case, each guest's virtual network card is assigned to a VLAN tag, +which is transparently supported by the Linux bridge. +Trunk mode is also possible, but that makes configuration +in the guest necessary. + +* *"traditional" VLAN on the Linux bridge:* +In contrast to the VLAN awareness method, this method is not transparent +and creates a VLAN device with associated bridge for each VLAN. +That is, creating a guest on VLAN 5 for example, would create two +interfaces eno1.5 and vmbr0v5, which would remain until a reboot occurs. + +* *Open vSwitch VLAN:* +This mode uses the OVS VLAN feature. + +* *Guest configured VLAN:* +VLANs are assigned inside the guest. In this case, the setup is +completely done inside the guest and can not be influenced from the +outside. The benefit is that you can use more than one VLAN on a +single virtual NIC. + + +VLAN on the Host +^^^^^^^^^^^^^^^^ + +To allow host communication with an isolated network. It is possible +to apply VLAN tags to any network device (NIC, Bond, Bridge). In +general, you should configure the VLAN on the interface with the least +abstraction layers between itself and the physical NIC. + +For example, in a default configuration where you want to place +the host management address on a separate VLAN. + + +.Example: Use VLAN 5 for the {pve} management IP with traditional Linux bridge +---- +auto lo +iface lo inet loopback + +iface eno1 inet manual + +iface eno1.5 inet manual + +auto vmbr0v5 +iface vmbr0v5 inet static + address 10.10.10.2 + netmask 255.255.255.0 + gateway 10.10.10.1 + bridge_ports eno1.5 + bridge_stp off + bridge_fd 0 + +auto vmbr0 +iface vmbr0 inet manual + bridge_ports eno1 + bridge_stp off + bridge_fd 0 + +---- + +.Example: Use VLAN 5 for the {pve} management IP with VLAN aware Linux bridge +---- +auto lo +iface lo inet loopback + +iface eno1 inet manual + + +auto vmbr0.5 +iface vmbr0.5 inet static + address 10.10.10.2 + netmask 255.255.255.0 + gateway 10.10.10.1 + +auto vmbr0 +iface vmbr0 inet manual + bridge_ports eno1 + bridge_stp off + bridge_fd 0 + bridge_vlan_aware yes +---- + +The next example is the same setup but a bond is used to +make this network fail-safe. + +.Example: Use VLAN 5 with bond0 for the {pve} management IP with traditional Linux bridge +---- +auto lo +iface lo inet loopback + +iface eno1 inet manual + +iface eno2 inet manual + +auto bond0 +iface bond0 inet manual + slaves eno1 eno2 + bond_miimon 100 + bond_mode 802.3ad + bond_xmit_hash_policy layer2+3 + +iface bond0.5 inet manual + +auto vmbr0v5 +iface vmbr0v5 inet static + address 10.10.10.2 + netmask 255.255.255.0 + gateway 10.10.10.1 + bridge_ports bond0.5 + bridge_stp off + bridge_fd 0 + +auto vmbr0 +iface vmbr0 inet manual bridge_ports bond0 bridge_stp off bridge_fd 0 @@ -287,5 +491,5 @@ iface vmbr0 inet static //// TODO: explain IPv6 support? -TODO: explan OVS +TODO: explain OVS ////