Is there an easy way to allow a single vSphere 5.0 host communicate on multiple subnets and allow VMs hosted there to communicate on those subnets?
I've got a small farm of vSphere 5.0 that are managed by a vCenter instance. For this farm, I've been allocated an internal /26 subnet (lets say it's 10.13.111.0/26).
Each vSphere host has two NICs in that are connected to a cisco 3750 switch as a "Route based on IP hash" trunk to give 2GBit bandwidth between each host and the switch. This link is also a .11q trunk. On the hosts themselves, I've got two virtual machine port groups, one on VLAN 118 called "Public" and the other on vlan 999 called "Private". The private VLAN is addressed in the 192.168.100.0/24 space and is used for inter-VM traffic. I have two VMKernel Ports both attached to the same 118 VLAN and addressed on the 10.13.111.0/26 network.
Here's what the configuration of one of the hosts looks like:
The problem is that I've run out of IP addresses in this subnet, and have been allocated another subnet - 10.13.110.0/26. However, if I add another VMKernel Port on VLAN 118 to this host and assign it 10.13.110.1, that IP address remains unreachable. I'm not sure if this is an issue on the switch or on the VMware vSphere host itself.
How can I configure this subnet to be usable by the host?
Just to add, the 3750 has VLAN118 defined as:
interface Vlan118 ip address 10.13.111.62 255.255.255.192 end
Can I just expand the definition to include the new subnet and have it all magically work?
This is looking like it's a switch config issue.
If I reconfigure the VLAN118 on the 3750 as follows:
interface Vlan118 ip address 10.13.111.62 255.255.255.192 ip address 10.13.110.5 255.255.255.192 secondary end
then the switch can now ping the VMKerenel device on the new .110 network. However, everything past the switch in the wider network can't ping the device.
The gateway for the .111 network is 10.13.111.3 and for the .110 network it's .110.3 - both of these IP addresses are hosted by a router that is connected to the core switch (or maybe even the core switch). I've got an uplink to that core switch from my 3750.
I guess that any traffic from .110 to .111 needs to flow from vSphere through my 3750 out to the core to .110.3, hop over to .111.3 and then back into my 3750 and into vSphere. Does that sound about right?