How to make 10.0.0.0/24 network communicates with 10.1.0.0/24?

[kent05]

Good day guys.

I have a homelab with following topology:

home router <----> cisco router <-----> cisco L3 switch <-----> ESXi host + vcenter in R710 server. 

Home router = 10.0.0.1

Cisco router = 10.0.0.2 / 10.1.0.1

Cisco L3 switch = 10.1.0.2

ESXi = 10.0.0.5

vCenter = 10.0.0.6

 I installed two AD DCs (DNS + DHCP roles) with ip addresses 10.1.10.1 & 10.2 respectively to serve for my 3 nested ESXi hosts with ip addresses 10.1.20.10, 30.10 & 40.10, respectively.  I also installed vcenter on each of the nested ESXi hosts with ip addresses 10.1.20.11, .30.11 & 40.11, respectively.

I can access 10.0.0.0/24 network through 10.1.0.0/16 network but not the other way round. Do I need to configure ospf in both cisco L3 switch & router? If yes how do I go about?   

[M02@rt37]

Hello @kent05 

You say 10.0.0.0/16 that cover ADDC, venter and ESXi hosts... where is configured the Gw of that /16 subnet ?

Or, do you have subneted this /16 and have different vlan on your L3 switch...

You talk about ospf too... please more elaborate and post if possible diagramm of your topology.

Thanks.

[kent05]

Hi M02@rt37 

Below is my home lab's network topology.I configured different vlans in L3 switch. Basically what I'm trying to achieve is I want to group all nested ESXi hosts into cluster in vCenter 8 (10.0.0.6) but unfortunately the vCenter failed to contact all nested ESXi hosts. Only those nodes in 10.1.0.0 /16 subnets can reach 10.0.0.0/24 subnet. 

[M02@rt37]

Thanks @kent05 

If I understand, the problem is that the home router (10.0.0.1) doesn’t know how to reach the 10.1.x.x VLAN networks sitting behind the Cisco router ?

So, add static route on the home router for the nested VLANs (10.1.0.0/16 or each /24) pointing to 10.0.0.2 or modify vcenter gw from 10.0.0.1 ->10.0.0.2 so all 10.1.x traffic is sent directly to the cisco router, which already know those subnets...

[kent05]

M02@rt37 

I have added 10.1.0.0/16 in the router but it is seem like doesn't work. 

[MHM Cisco World]

10.0.0.0 appear in your network twice 

That not correct.

MHM

[kent05]

Hi @MHM Cisco World 

Which part does 10.0.0.0 appear in my network twice? 

[MHM Cisco World]

VCenter have 10.0.0.0/24 and between home and router you use 10.0.0.1 and 10.0.0.2 !!!!

You need to change one of them

MHM

[kent05]

@MHM Cisco World 

Why can't vCenter have same 10.0.0.0/24 subnet with home router and cisco router with 10.0.0.1 and 10.0.0.2?

[MHM Cisco World]

In your network you can not have same subnet in two link 

This make other l3 device confuse' forward 10.0.0.0 traffic to which device ?

Change vcenter subnet 

Then 

1- in L3SW run ip routing 

2- in LSW use defualt route toward Cisco router 

3- in cisco route use static route toward l3SW for each vlan connect to it 

4- in cisco router use NAT'

Why NAT? I think you can not add route to home router so' home router only see Cisco router IP' behind this IP it dont known anything' so we NATing VLAN in Cisco router to IP reachable by home router.

MHM

[kent05]

Which subnet should I use? I have enabled ip routing in the switch. The default route is 0.0.0.0 0.0.0.0 10.1.0.1.

Cisco router's static route is 0.0.0.0 0.0.0.0 10.0.01 & 10.0.0.0 255.0.0.0 10.1.0.2. I also configured ACL & NAT.