Problems running 3 subnets on a single ESX host with vCenter installed.

[craigf01]

Hi,

I am not especially proficient in VMware networking, so would like to ask for some assistance on how I can run three subnets on a single ESX host. I have currently only got management and my first site networks configured.

I have an ASUS router which I have created routes to the required networks and I can ping the physical nics on the ESX host from my client machine. From within vCenter, on the guest VM's I can ping the ESX NIC associated to the relevant network, but cannot ping the outside world from the VM.

I am attempting to create a Lab environment and the following is the addressing I am using:

Router: 172.168.30.254 \24

ESX host (mgmt): 172.168.30 1 \24

vCenter: 172.168.30.30 \24

Site1 vmnic: 172.168.0.1

VMFILE1: 172.168.10.5

VMSQL1: 172.168.10.6

Below are screenshots of my configuration, it is probably something silly I have missed but thought Id ask the question here:

So from the screenshots and details above, can anyone tell me how I can create three networks in total on a single ESX host, that I can get access to the virtual machines on the subnets? I hope I have described this well enough

Any assistance is much appreciated!

[scott28tt]

Moderator note: Moved to ESXi

[jburen]

So you want to have three separate networks on an ESXi host? You could create a vSwitch with three port groups. You connect the vmnic0 (thats the nic from the host) to the vSwitch as an uplink. As with a normal switch there is no relationship between a vSwitch and a subnet. So if you want to use different subnets you should use VLANs. You can assign a VLAN to a port group so every VM connected to that port group will be placed in that VLAN (with its own subnet).

However, when you do that AND you want to connect the VLANs together, you must use a router and create a trunk port for the port that is being used by your ESXi host. Otherwise, the VM's inside a port group can communicate with eachother but not with a VM in another port group.

I hope it makes sense...

[craigf01]

Hi Jburen,

Thanks for getting back to me.

I created a port group named "site1" and added vmnic2 as its uplink. This was to be the 172.168.10.0/24 network. I have added this adapter (physical) to my VCSA and given it an ip address of 172.168.10.1.

I can ping that address from outside of my esx server and can also ping the management port of esx on 172.168.30.1 as well as my management address on vCenter of 172.168.30.30.

My virtual machines in this port group have ip addresses of 172.168.10.5 & 6, I cannot ping any of those from outwith the esx host. I can ping both from esx cli and also from vcenter cli.

So i am not sure if it routing that I need to configure correctly or something else that I am missing. I have put a screen shot of the routing existing on the VCSA:

As I can only have one Gateway, it is on the management network interface eth0. My two other networks will be attached using eth1 (172.168.10.0/24) and eth3 (172.168.20.0/24).

I guess what i really need is a step by step to make these connections work, or to be advised its not possible with the equipment I am using.

1. Physical server with x3 nics

2. Asus Wireless router (RT-N66U​)

The route I have configured on the router is shown above in the router screen shot. I have followed the below link, with regard to configuring my VLAN but still no joy, I cannt access the VM's from a client outwith ESX, RDP or ping.

VMware Knowledge Base

No firewalls are running either.

Im sure I am missing something, just cant see the wood for the trees, so any assistance is much appreciated on this.

Cheers

Craig

[jburen]

If your physical server has 3 nics you could create three vSwitches and give them their own vmnic. Also create three IP stacks corresponding to the three subnets. Create a route for every subnet and point it to the IP address of the IP stack that you use for the vSwitch. I can't give you a screenshot because my server at home only has one nic.