I have a windows 2003 server running under vmware esx.
For weird reasons, outside of our control, sometimes the guest tcp/ip stack stops working. So, for example, remote desktop connections don't work.
My goal is trobleshooting this network ( and other ) guest errors.
I can develop and put inside the guest some scripts, to monitor and detect tcp/ip and other application specific faults.
Can I run some console tool, to report a fault from the guest to the hypervisor ?
This tool has to work without network's apis, due to the failures we want to troubleshoot. I think it is possible : the supervisor works, I use it while the guest tcp/ip stack was faulty.
You should try to resolve the root of the problem, not merely be alerted when it happens. Your first stop is to check your Windows logs for any errors. Try to determine if the problem is one service in particular (Terminal Services), or a general networking issue.
Networking in virtual machines is generally pretty stable (or at least consistent), if you install VMware Tools. If you have VMware Tools installed and it is still giving you trouble, try uninstalling VMware Tools and reinstalling with all of the drivers (not just the ones you need).
Finally, try a different network adapter type. When you add a network adapter in ESX/ESXi, you get to choose which "type." You can't change the type of an already existing adapter, but you can remove the current one and add a new one while it's running. Try E1000 if you're using VMXNET, and vice versa. I've had issues with one where another adapter type had none.
Is there any reason you can't just monitor connectivity to port 3389 (RDP) on the VM using whatever monitoring system you've already got deployed without having to get the hypervisor installed? Your description of this problem doesn't make it seem VM-specific in the slightest.
(I'd argue that if RDP is an important piece of your remote administration strategy, you should be monitoring it on all of your servers, not just this one.)