[pve-devel] [PATCH docs] add VLAN explanation.

[Wolfgang Link]

---
 pve-network.adoc | 88 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 88 insertions(+)

diff --git a/pve-network.adoc b/pve-network.adoc
index d221c32..c5d5b40 100644
--- a/pve-network.adoc
+++ b/pve-network.adoc
@@ -344,6 +344,94 @@ iface vmbr0 inet static
 
 ----
 
+VLAN 802.1Q
+~~~~~~~~~~~
+
+A virtual LAN (VLAN) is any broadcast domain that is partitioned and isolated in network at layer 2.
+So it is possible to have multiple networks (4096) in a pysical network.
+VLANs uses tags on network package to identify the affinity to the virtual network in the network.
+
+One or more VLANs can be used on any network device (Nic, Bond, Bridge).
+There are several ways to configure VLANs.
+Here only those based on linux network (not OpenvSwitch) recommended by us,
+which we have selected according to the following points.
+Simple configuration and clarity.
+Of course, there are scenarios that are not possible with this configuration
+but it will work for most standard setups.
+
+There are two basic usage scenarios in which you can find VLANs.
+
+1.) VLAN on the host, to bring the host communication to a isolated network.
+As already mentioned, it is possible to apply the VLAN to all network devices.
+In general, you should configure the VLAN as close as possible to the physical NIC.
+For example, in a default configuration in which you want to place the host management address on a separate VLAN, consider the VLAN on the physical NIC, not the bridge (vmbr0).
+
+.Example: Use VLAN 5 as managment IP
+----
+auto lo
+iface lo inet loopback
+
+iface eno1 inet manual
+
+auto eno1.5
+iface eno1.5 inet static
+        address  10.10.10.2
+        netmask  255.255.255.0
+        gateway  10.10.10.1
+
+auto vmbr0
+iface vmbr0 inet static
+        bridge_ports eno1
+        bridge_stp off
+        bridge_fd 0
+
+----
+
+If you want to make this network fail-safe (bonding),
+does the VLAN have to be created on the bond?
+
+.Example: Use VLAN 5 as managment IP on bond0
+----
+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
+
+auto bond0.5
+iface bond0.5 inet static
+        address  10.10.10.2
+        netmask  255.255.255.0
+        gateway  10.10.10.1
+
+auto vmbr0
+iface vmbr0 inet static
+        bridge_ports bond0
+        bridge_stp off
+        bridge_fd 0
+
+----
+
+2.) VLAN for the guests.
+Proxmox supports 3 different ways of using VLAN in guests.
+
+* *VLAN with VLAN awareness on the Linux Bridge:* In this case, each guest's virtual network card is assigned a VLAN tag, which is transparently supported by the Linux Bridge.
+This requires a guest who wants to use multiple VLANs to have multiple virtual NICs.
+This method is the procedure recommended by Proxmox.
+
+* *VLAN with "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, if e.g. in our default network, a guest VLAN 5 is used to create ens1.5 and vmbr0v5, which remains until rebooting.
+
+* *VLAN in guest:* There, the VLANs are assigned in the guest.
+In this case, the setup is in the guest and can not be influenced from the outside.
+
 ////
 TODO: explain IPv6 support?
 TODO: explain OVS
-- 
2.11.0