in need of an explanation... VMWARE

So you have an ESXi host server on network 10.75.13.x, with a default gateway of 10.75.13.x ?

You have a virtual machine with 10.75.153.x, and the default gateway of 10.75.153.x, which is both acceptable, A Host can Host VMs, on different networks and VLANS.

A VM not be able to communicate is not a Host issue, it's how networking has been configured on host and physically attached and configured.

So what's the issue ?

I cannot communicate on my 152 network, from what Host or VM or both ?

what should be able to communicate?

Can the VM reach the default gateway? e.g. ping it ?

Have you connected and created a virtual machine portgroup, connected to this VLAN (10.75.152.x)

I have one network card with 13.x on the ESXI server.  I have 2 gbics connected to a SAN.  I just installed a 2012 server with a 10.75.152.x and I can't communicate or even ping my domain controllers.  These two subnets are on the same vlan.  I can't ping the gateway for the 152 side.

and you Domain Controllers are on which network ?

So you run a VLAN, which carries subnets 10.75.152.x and 10.75.13.x ?

traffic from 10.75.152.x to reach 10.75.13.x needs to go through a router?

do you have a router currently in the physical world, do you have physical computers currently on 10.75.152.x and 10.75.13.x

can the host ping 10.75.152.x?

if you cannot ping the gateway/router, then this is the issue, it cannot route traffic.

So even though I have one network card on that vlan with a different IP (13.x) I'll need an additional nic card to communicate on the 152 side?

Well I think the only way around this is to buy more nic cards for the servers.

You state that you have two subnets running on the same VLAN?

is this true?

e.g. if you have two networks, lets save 192.168.1.x, and 10.10.1.x both running on the same physical wire, (which could be considered a VLAN), both cannot communicate with each other, unless there is a router, to route traffic between them ?

if these were in different VLANS

e.g.

192.168.1.x - VLAN20
10.10.1.x - VLAN30

again, some routing still needs to happen for traffic to reach each network, this could be a router, or INTER-VLAN ROUTING option, on the physical switch.

adding an extra network interface, is not going to make routing happen. ESXi provides not routing.

or you connect network interfaces to the correct networks.

I believe my issue is the routing.  I need to build vmswitches and use nic cards that's what I've done on my other machines.
There's no router between anything they are all connected via the same nic card.  I have 172.x.x.x connecting to my SAN and 10.75.13.x connecting to the network.  I can't build another switch without another nic card to route it out. Right?

I believe my issue is the routing.  I need to build vmswitches and use nic cards that's what I've done on my other machines.

in that case you have connected vSwitches/uplink - network interfaces to those dedicated networks.

There's no router between anything they are all connected via the same nic card.  I have 172.x.x.x connecting to my SAN and 10.75.13.x connecting to the network.  I can't build another switch without another nic card to route it out. Right?

to build a new vSwitch, connected to a different physical network, does require a new nic.

So 172.x.x.x and 10.75.13.x run on the same network which is fine, but they will not communicate with each other, ever - the same with 10.75.153.x.... that will not communicate with 10.75.13.x  or 172.x.x.x.

Do you want a device with IP Address 10.75.153.x to communicate with device with IP address 10.75.13.x   ?

Yes basically that's what I want.  This is what I have.
vmcurrent.png

The problem is the 4 (2 Ethernet and 2 gbics) are all one card - so I can't change the IP.  but I understand what you're saying thanks.