KVM multiple guest vm having same ip address through NAT

Ask Fedora
1

I want to create multiple qemu guest vm through packer but both the vm getting same ip 10.0.2.15 and mac address also is same.
Then i have added mac address for both the vm as below, but still same mac and same ip is getting assigned and mac address hardcoded is different that what assigned to guest vm every time, can anyone please help

Also after updating default.xml through sudo virsh net-edit default , destroyed and started it and restart libvirtd.

this is my default.xml

<!--
WARNING: THIS IS AN AUTO-GENERATED FILE. CHANGES TO IT ARE LIKELY TO BE
OVERWRITTEN AND LOST. Changes to this xml configuration should be made using:
  virsh net-edit default
or other application using the libvirt API.
-->

<network>
  <name>default</name>
  <uuid>987ec465-087a-4a1b-9b46-218b92df34f0</uuid>
  <forward mode='nat'>
    <nat>
      <port start='1024' end='65535'/>
    </nat>
  </forward>
  <bridge name='virbr0' stp='on' delay='0'/>
  <mac address='52:54:00:f7:e2:09'/>
  <domain name='testenv' localOnly='no'/>
  <ip address='192.168.122.1' netmask='255.255.255.0'>
    <dhcp>
      <range start='192.168.122.2' end='192.168.122.254'/>
      <host mac='52:54:00:0a:f3:8d' name='aux-node' ip='192.168.122.20'/>
      <host mac='52:54:00:90:bf:39' name='app-node' ip='192.168.122.21'/>
    </dhcp>

packer json file through building 2 guest vm, i am using these 2 parameters also “net_device”: “virtio-net”, “disk_interface”: “virtio”,

{

"builders": [

{

"type": "qemu",

"name": "aux-node",

"qemu_binary": "/usr/libexec/qemu-kvm",

"iso_url": "/var/lib/libvirt/images/test.iso",

"iso_checksum": "md5:14029d4c94b74492ee4c97f2f736390a",

"output_directory": "/var/lib/libvirt/images/iso-dir/auxtest",

"disk_size": "350G",


"headless": "true",

"qemuargs": [

            [
                 "-m",

                "8000"

            ],
    [
        "-cpu",
                "host"
            ],
            [

                "-smp",

                "4"

            ]
    
 ],

"format": "qcow2",

"accelerator": "kvm",

"ssh_username": "*****",

"ssh_password": "*****",
"ssh_timeout": "20m",


"vm_name": "auxtest",

"net_device": "virtio-net",

"disk_interface": "virtio",


"http_directory": "/home/sogouser/http",


"boot_wait": "10s",

"boot_command": [

"<down><tab><bs><bs><bs><bs><bs>text ks=http://{{ .HTTPIP }}:{{ .HTTPPort }}/anaconda-ks.cfg<enter><wait>"
]

},

{

"type": "qemu",

"name": "app-node",
"qemu_binary": "/usr/libexec/qemu-kvm",

"iso_url": "/var/lib/libvirt/images/test.iso",

"iso_checksum": "md5:14029d4c94b74492ee4c97f2f736390a",

"output_directory": "/var/lib/libvirt/images/iso-dir/apptest",

"disk_size": "150G",


"headless": "true",

"qemuargs": [

            [

                "-m",

                "40000"

            ],
    [
        "-cpu",
                "host"
            ],
            [
                 "-smp",

                "8"

            ]
    
 ],

"format": "qcow2",

"accelerator": "kvm",

"ssh_username": "***",

"ssh_password": "****",

"ssh_timeout": "20m",


"vm_name": "apptest",

"net_device": "virtio-net",

"disk_interface": "virtio",


"http_directory": "/home/sogouser/http",
"boot_wait": "200s",

"boot_command": [

"<tab><bs><bs><bs><bs><bs>text ks=http://{{ .HTTPIP }}:{{ .HTTPPort }}/anaconda-ks-app.cfg<enter><wait>"
]

}

]
2

Check the output:

virsh list --all; sudo virsh list --all; sudo virsh net-list --all
3

sudo virsh list --all and virsh list --all has no output and sudo virsh net-list having default as output.

When I have used virt-install to create guest vm then with the above command I was able to see the guest vm in the outputs, but here I have used qemu so when guest vm also created then virsh list has no output.

I have build guest vm through packer and used plugin qemu so in the packer logs I can see it is able to build guest vm , login to vm and run scripts after that. Everything is automated through packer json file that I have attached earlier

So as of now it was working fine with single guest vm, but with multiple guest vm it giving same IP to all vm created.

I have stuck in this from last 2 week hoping here will get some help

4

Do not use low-level commands like qemu-*.
Use only high-level libvirt client tools like virsh, virt-install, or virt-manager.
Then you can attach a virtual bridge interface to a VM like this:

virsh attach-interface VM bridge VIF --model virtio --persistent
5

Thanks for the reply but any reason not to use qemu. As packer supports qemu but not supports virt-install

6

Your virtual network is managed libvirt, but your VM is not.
This makes it problematic to properly integrate them together.
Convert the VM config from JSON to XML and import it to libvirt.
Or use the settings from the JSON to import the VM with virt-install.
This will allow you to connect multiple VMs to your virtual network.

7

Thanks. I will try with virt-install, but is there a way to fix my current issue in qemu?