KVM difference Bridget, routet and NAT

[vikozo]

Hello
i try to understand what exactly the difference is between a KVM which is Bridget, routed or nated?
any help or pointing me to a Design which Show the difference.

so far i believe
a Bridged KVM would be used for use in the Local LAN (Samba/File/Music/Video Server)

but which (NAT or Routed) would fit best for a WEB/Mail Server, when i have only on Public IP?
Would it be also possible to use two or more KVM Web/Mail Server with on Public IP Adresse?

have a nice day
Vincent

 

[wolfgang]

Hi,
Bridge Network are used if you have for each Vm an own Ip address.

Nat or Routed Network are used if you have only 1 or not enough Ip's for every VM.

see
https://en.wikipedia.org/wiki/Network_address_translation
https://en.wikipedia.org/wiki/Routing

 

[vikozo]

Hello Wolfgang
thanks for your answer.
i have lots of Privat Address. 192.168.x.x
or do you mean Public IP?
have a nice day
vincent

 

[pirateghost]

Hello Wolfgang
thanks for your answer.
i have lots of Privat Address. 192.168.x.x
or do you mean Public IP?
have a nice day
vincent

Think of it like this:
If this is a simple configuration/server on a private subnet and you want all VMs to be on the same network as your physical machines, you use bridge.

If you want to have the VM host act as a router and have all VM traffic go through it and not see your LAN, you use NAT.

If your VM host is in a data center not under your control and you only have one/few IP addresses, you will want to use NAT or routed, so that all the traffic is behind the one/few ips you have.

 

[vikozo]

@pirateghost
thanks a lot - this is now clar.
But more question will for sure follow, most to make claer...

 

[vikozo]

hello
in Proxmox you could do some vmbr and give some IP Adresse but it is only possible to add to one vmbr a gateway.
so what is the reason to have multiple vmbr Bridge?

have a nice day
vincent

 

[pirateghost]

hello
in Proxmox you could do some vmbr and give some IP Adresse but it is only possible to add to one vmbr a gateway.
so what is the reason to have multiple vmbr Bridge?

have a nice day
vincent

You can connect different subnets, vlans, have private VM only networks, etc. Many options and configurations.