I'm in the middle of setting up a lab with a VRRP configuration, and I'm trying to search for any possible issues we might run into in production.
One issue I am aware of with VRRP is that it seems that STP convergence time (of about 45 seconds I believe) can sometimes cause the VRRP nodes to flap.
According to my diagram, I can't see any loops (ignoring the multi-homed servers at the bottom), so I suppose I can just disable STP and forget about it. But I'd like to see what happens with STP enabled, all the same.
I am using Vyatta Core 6.5 for both ISPA and ISPB's routers. I am running the VMs on VMWare workstation.
The reason my lab includes switches between ISPA and ISPB is that in production we are using these to terminate the fibre uplinks to our provider. So I've tried to make my lab as close to production as possible.
My configuration is like so:
My issue is that, right now, the switches don't actually exist in my lab. I am simply using LAN Segments in VMWare workstation to allow the Vyatta VMs to talk to one another. My issue is that because all the connections between VMs is done inside the Hyervisor, it seems there is no possibility to test things like this.
My question is: Can someone think of a way of connecting these VMs together in such a way that it would simulate physical Vyatta machines connected via Cisco (or otherwise) switches, so that I can test STP (and anything else I can think of)?
What I've tried
Using GNS3 to inter-connect VMs
One thing I have tried doing is getting the VMs to communicate via GNS3 using VMNet Host-Only adapters to integrate with GNS3, then using a Cisco 3745 with a FastEthernet switching module added. There's a few issues here:
- In my lab I am using a single subnet to talk between ISPA and ISPB (10.11.246.0/29).
- VMWare expects that a single VMNet adapter uses a single subnet, so I cannot use multiple separate VMNet adapters with the one 10.11.246.0/29 subnet.
- In any instance where two VMs use the same VMNet adapter, packets are sent directly to each other, and so without separate VMNet adapters, I can't see a way forcing the VMs to communicate via a GNS3 router.
- My understanding is that with VRRP, using a subnet smaller than what could accomodate all nodes + virtual IPs would be considered a hack and not advisable. So for example, using /30s and multiple VMNet adapters is not a good idea.
- I am open to using other Virtual Machine platforms such as virtual box.
- I have a physical Cisco Catalyst 2950 at my desk, and the host machine has two physical NICs available.