4 Replies Latest reply on Sep 13, 2019 11:38 AM by Sureshkumar M

    Config network adapter

    heinzfelfe Lurker



      ... this is rather a question for configuration work ... hope it's ok.


      In a LAN of another company, we do not have physical access to, we run a DELL Machine (Poweredge 730).

      We vitualized the machine with ESXi (ESXi 5.5) into several VMs, all of which have an external IP.


      Now I want to create a new VM I only have an internal IP for ...

      The standard-switch (vSwitch0) has a physical adapter "vmnic0" with the ip range:



      Which includes of course our external IPs.

      The company simply plugged a cable to the Poweredge and gave us an internal ip (say:


      So I created an additional standard-switch (vSwitch1) with a physical adapter "vmnic1".

      But where can I add the ip - range ? Or will it be assigned after a reboot of the Poweredge ?


      For the additional VM I do not need a domain. It's only for internal services. the network config in

      /etc/network/interfaces looks sane to me:



      source /etc/network/interfaces.d/*  # empty directory



      auto lo

      iface lo inet loopback



      allow-hotplug ens32

      iface ens32 inet static



              dns-search database





      Non-the-less I cannot connect to other machines e.g. via ssh.



      Can you get me started in order to connect it to the LAN network ?



      On that machine i put a Debian. Is it possible to run updates to the os e.g. with apt, only

      having an internal IP ?



      ... would be grateful for some help here.



      Best and Thanks,




        • 1. Re: Config network adapter
          Sureshkumar M Expert

          From my understanding , you want that debian VM to connect to the internal network using the IP provided. Correct me if I am wrong. Just to isolate the issue


          Right now, another standard switch has been created using vmnic1 which is connected to the other internal network setup. Now our aim is to make the debian VM to get connected via that uplink and access the internal network


          1. Have you created a virtual machine port group on new standard switch ?

          2. Right now the VM should be having two virtual nic cards (one is configured with external IP and attached to the vSwitch of external network and another vnic should be configured with the internal IP provided ), the internal vnic should be connected to the portgroup created on vSwitch 1 .


          Can you please clarify the above points.



          But where can I add the ip - range ? Or will it be assigned after a reboot of the Poweredge ?

          This actually depends on the requirement, if you want your ESXi to communicate with internal network, then you have to create a vmkernel adapter on vSwitch and assign an IP to it.

          If you want your virtual machine to communicate with internal network, you have to create a virtual machine portgroup as stated above and assign an IP to the VM to communicate with the network. 

          • 2. Re: Config network adapter
            Shrikant_Gavhane Enthusiast

            Apologies the question does not seem clear. Below is my understanding.


            1. you have one of the uplink which has network visible - (external IP's) (vswitch 0)

            2. You want to create a VM with internal IP's only.

            3. Company gave you one uplink with internal network visible to it  (say (vswitch 1)


            Your question is " where can I add the ip - range ? Or will it be assigned after a reboot of the Poweredge ?"


            As question is unclear I am writing all the possibilities I can think of as answer.


            1. If you are looking for your VM1 to have internal network access -> Create one VMNIC and tak to vsiwth 1, assign IP from OS end.

            2. If you are looking for your VM1 to have external network access -> Create one VMNIC and tak to vsiwth 1, assign IP from OS end.

            3. Internal and external NIC's can be made available on the VM1 and assigned IP.

            4. If you are looking for IP assignment to esxi, kindly create vmknic on vswitch1 and assign it a internal IP. that will be used for esxi communication.


            Thanks and Regards,

            Shrikant Gavhane

            • 3. Re: Config network adapter
              heinzfelfe Lurker

              Hi all,


              sorry for my belated reply and THX for your info !!!

              In the meantime I was very busy and could not answer ... hope you are willing to help me one more time.


              Your understanding is right.

              So the next thing to is to create a "virtual machine port group".


              The first picture shows my situation:



              I have one physical adapter connected to my Standard-vSwitch0 with my productive servers

              Server 1

              Server 2

              Server 3



              Then I created another Standard-vSwitch1 I assigned the VM to I want to connect

              the internal network to. Maybe this is wrong, because I have only one physical adapter



              But what IP do I have to set in Standard-vSwitch1. and how  to configure the networks ?

              The networks ( - assigned to Standard-vSwitch0 are displayed on the next picture





              Or where to set the "virtual machine port group" ? Standard-vSwitch0 ?

              Do I also need another VMkernel-Port ?





              Looking forward to you answers!




              • 4. Re: Config network adapter
                Sureshkumar M Expert

                ok, here is the point . Now vSwitch 0 having three virtual machines and one vmkernel adapter for ESXi management network with external connectivity is working fine.


                Coming to the internal network part, we have created another vSwitch 1 with vmnic1 .


                1. First , there is no physical connectivity on the other end of vmnic , thus it shows the red cross mark. Connect the cable to your another server or switch which will take you to the internal network.

                2. What is the IP range for your internal network ? Take a free IP from that range and assign to the virtual machine "Database server" which needs connectivity internal network.


                By this way you can achieve the goal.


                Just to clarify the networking part


                You have two types of port group that can be created in a virtual switch


                1.   vmkernel port group , this is a network assignment/setting which is for your ESXi host. Like how your configured in vSwitch0 with and IP using which you are interacting with the ESXi host. This is not mandatory for all the vSwitches , you can create as per your requirement.

                2. Virtual machine portgroup -- this is nothing but a group of virtual machine network, here you will just create the port group , IP assignment will happen inside the guest OS of the virtual machine. You need not assign IP at vSwitch level while creating port group unlike vmkernel adapter.


                And for both port group types in a vSwitch, you need atleast one physical network card which is called as uplink used for  connectivity to physical network.


                In your scenario, you want the "database server" VM should be connected to your internal network . So you do not need to create a vmkernel portgroup on second vSwitch, just assign an IP as I mentioned in my two points and establish the connectivity. Feel free to ask if it is not clear or if my understanding is wrong.