vlan and vswitch

Running out of IP Addresses for VMware ESXi servers, or virtual machines?

Create a class B.

Before you do that you may also want to consider what is on the C and if you are better server with multiple C subnets to create barriers, this will require intervlan routing however so that network 192.168.0.x can talk to machines on 192.168.1.x

If it is just one or a few subnets you need to adjust you can supernet the class C addresses to combine multiple class C ranges into a single logical subnet.  You would need adjacent class C subnets not in use to make it work and you would likely need to know a bit about subnetting your addresses.

For example, if you were using 192.168.2.0/24 and you needed twice as many addresses you could do 192.168.2.0/23 which would consume the adjacent 192.168.3.0/24 subnet and make one range of 192.168.2.0-192.168.3.255.  You would need to possibly adjust some routing on your network but it should be fairly simple, as long as you have that adjacent IP range, and it falls within the same range when you adjust the mask (for example, my previous example of a /23 mask wouldn't work for 192.168.1.0 and 192.168.2.0 to combine them).  If you don't understand that concept you might need to read up on subnetting.

i am running out of vms ip address . Right now my vms ip are 192.168.1.*/24 and my iscsi storage ips are 192.168.2.*.

suppernetting 192.168.1.*/23 is not going to help since the adjacent 192.168.2.*/24 is being used by iscsi.
my network admin suggested me to create another port group in the existing vswitch (192.168.1.*/24) .
and name this as lan2 and give ip address for the server in the network 192.168.3.*/24).
Creating a port group is not an issue for me, but what else i have to do to make sure that servers will talk, is that right approach?
i am willing to change the ip from class c to class b, this can be lot of problem . down time and changing nat ip etc.
Bryant:
You mentioned about inter vlan , is it something in the vmware or the network guy will do that?