Public IP on KVM

[Waldek]

Hello,

i'm trying to setup a public IP on my VM and i can't get it to work.

My host interfaces file is:

auto lo
iface lo inet loopback
iface eth0 inet manual

auto vmbr0
iface vmbr0 inet static
address xxx.xxx.131.201
netmask 255.255.248.0
gateway xxx.xxx.128.1
bridge_ports eth0
bridge_stp off
bridge_fd 0

there's only one network interface on host: eth0.

I have also a public IP address:

address xxx.xxx.139.247
netmask 255.255.255.255

which i want to set on my VM.
My VM interfaces file is:

auto lo
iface lo inet loopback

auto ens18
iface ens18 inet static
address xxx.xxx.139.247
netmask 255.255.255.255
gateway xxx.xxx.128.1

but this isn't working.

I can connect to host machine using both addresses with configuration:
auto lo
iface lo inet loopback

auto eth0
iface eth0 inet static
address xxx.xxx.131.201
netmask 255.255.248.0
gateway xxx.xxx.128.1

auto eth0:1
iface eth0:1 inet static
address xxx.xxx.139.247
netmask 255.255.255.255
gateway xxx.xxx.128.1

I've tried different configurations, read a lot of threads with similar problems and still don't know how to configure this properly.

Thank you for your help.

 

[boopzz]

Why do you give Proxmox a public IP? Also have you set the VM bridge as vmbr0?

 

[Waldek]

Why do you give Proxmox a public IP?

Becouse I want to host a webpage on that virtual machine.

Also have you set the VM bridge as vmbr0?

Yes, using proxmon webinterface.

 

[Waldek]

Maybe i'll explain a little more what i trying to achieve:
I have a dedicated server with public IP on which i want to host 3 KVMs.

root@server:~# pveversion
pve-manager/3.1-3/dc0e9b0e (running kernel: 2.6.32-23-pve)

For now i have interfaces file with 4 IPs:

auto eth0
iface eth0 inet static
        address xxx.xxx.131.201
        netmask 255.255.248.0
        gateway xxx.xxx.128.1

auto eth0:1
iface eth0:1 inet static
        address xxx.xxx.139.247
        netmask 255.255.255.255
        gateway xxx.xxx.128.1

auto eth0:2
iface eth0:2 inet static
        address xxx.xxx.137.129
        netmask 255.255.255.255
        gateway xxx.xxx.128.1

auto eth0:3
iface eth0:3 inet static
        address xxx.xxx.142.40
        netmask 255.255.255.255
        gateway xxx.xxx.128.1

and i'm able to connect to the host using any of them.

root@server:~# ifconfig
eth0  Link encap:Ethernet  HWaddr 00:25:90:c1:ff:ea
  inet addr:xxx.xxx.131.201  Bcast:xxx.xxx.135.255  Mask:255.255.248.0
  inet6 addr: xxxx::xxx:xxxx:xxxx:xxxx/64 Scope:Link
  UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
  RX packets:5425 errors:0 dropped:0 overruns:0 frame:0
  TX packets:2504 errors:0 dropped:0 overruns:0 carrier:0
  collisions:0 txqueuelen:1000
  RX bytes:406582 (397.0 KiB)  TX bytes:215557 (210.5 KiB)

eth0:1  Link encap:Ethernet  HWaddr 00:25:90:c1:ff:ea
  inet addr:xxx.xxx.139.247  Bcast:xxx.xxx.139.247  Mask:255.255.255.255
  UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1

eth0:2  Link encap:Ethernet  HWaddr 00:25:90:c1:ff:ea
  inet addr:xxx.xxx.137.129  Bcast:xxx.xxx.137.129  Mask:255.255.255.255
  UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1

eth0:3  Link encap:Ethernet  HWaddr 00:25:90:c1:ff:ea
  inet addr:xxx.xxx.142.40  Bcast:xxx.xxx.142.40  Mask:255.255.255.255
  UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1

lo  Link encap:Local Loopback
  inet addr:127.0.0.1  Mask:255.0.0.0
  inet6 addr: ::1/128 Scope:Host
  UP LOOPBACK RUNNING  MTU:16436  Metric:1
  RX packets:114 errors:0 dropped:0 overruns:0 frame:0
  TX packets:114 errors:0 dropped:0 overruns:0 carrier:0
  collisions:0 txqueuelen:0
  RX bytes:60540 (59.1 KiB)  TX bytes:60540 (59.1 KiB)

venet0  Link encap:UNSPEC  HWaddr 00-00-00-00-00-00-00-00-00-00-00-00-00-00-00-00
  inet6 addr: fe80::1/128 Scope:Link
  UP BROADCAST POINTOPOINT RUNNING NOARP  MTU:1500  Metric:1
  RX packets:0 errors:0 dropped:0 overruns:0 frame:0
  TX packets:0 errors:0 dropped:3 overruns:0 carrier:0
  collisions:0 txqueuelen:0
  RX bytes:0 (0.0 B)  TX bytes:0 (0.0 B)

root@server:~#

I'm trying to create 3 KVMs:
KVM1 using xxx.xxx.139.247 as public IP
KVM2 using xxx.xxx.137.129 as public IP
KVM3 using xxx.xxx.142.40 as public IP

The question is how to setup interfaces file on host and vm?

 

[Waldek]

Ok, finally got it working:

Host:

auto eth0
iface eth0 inet static
  address xxx.xxx.131.201
  netmask 255.255.248.0
  gateway xxx.xxx.128.1

auto vmbr0
iface vmbr0 inet static
  address xxx.xxx.131.201
  netmask 255.255.248.0
  bridge_ports none
  bridge_stp off
  bridge_fd 0
  bridge_maxwait 0

  up ip route add xxx.xxx.139.247/32 dev vmbr0

VM:

auto eth0
iface eth0 inet static
  address xxx.xxx.139.247
  netmask 255.255.255.255
  pointopoint xxx.xxx.131.201
  gateway xxx.xxx.131.201
  dns-nameservers 8.8.8.8 8.8.4.4

 

[boopzz]

Unless Proxmox is working as a firewall (but I'd seriously consider setting up a Proper firewall VM for this) then I would NOT give Proxmox a Public IP address!

Bridge the internet physical interface to your vmbr0 and attach the VMs to that. Or what I would do is setup a Firewall VM and setup one IP as the interface IP and the other 2 as one to one NAT to your VMs inside a 'DMZ' which actually have Private IPs

 

[Chaminda Bandara]

Unless Proxmox is working as a firewall (but I'd seriously consider setting up a Proper firewall VM for this) then I would NOT give Proxmox a Public IP address!

Bridge the internet physical interface to your vmbr0 and attach the VMs to that. Or what I would do is setup a Firewall VM and setup one IP as the interface IP and the other 2 as one to one NAT to your VMs inside a 'DMZ' which actually have Private IPs

According to my knowledge this is the best practice, but I have no much knowledge how to setup step by step and low level architecture wise.

Could you please share a good resource (Tutorial) may be a video or a web ?

 

[mucua]

Any ideas on how would the config file be for a centos vm/guest?