Intermittent connectivity to Single Server on MPLS
Posted on 2013-05-22
We recently switched from IPSEC VPN between two Sonicwalls to MPLS via our provider. At each site the MPLS cisco router is connected to our LAN switch. That LAN switch plugs into an interface on our Sonicwalls. We have three sites: A, B, and C. Site B is the datacenter and houses the server with the issue. The server is a Win 2008 DC with DHCP/DNS, IP 10.22.22.208. At Site A I have a laptop on IP 10.23.23.100.
The issue is that since we have switched to the MPLS if I do a continuous ping from my laptop in Site A to the server in Site B. The pings drop regularly. Likewise, if I do from server to laptop. I see the same issue if I ping from server in site B to site C, which is another site with MPLS. Basically, I can reach the LAN interface of the MPLS router but not beyond it.
What's cooking my noodle is I can successfully reach all other servers in that subnet. I can reach 10.22.22.x where x isn't 208.
I've worked with Sonicwall and our MPLS provider and both are clueless.
Sonicwall confirmed my routes in the sonicwalls were correct, and this is easily proven considering I can hit every other server without incident. MPLS says it's LAN problem since they can get to/from their interfaces on the ciscos without loss.
I keep thinking it's got to be the server but what on the server would cause the pings to time out more than half the time. I powered this server off to check for dupe IP but didn't find one. I also rebuilt NIC as this is virtual machine. Yes, I can reach all other VM's on this host without timeouts.
Any experts care to swing at this? Lost cause right?