I have two virtual servers that sit in my DMZ subnet. Pinging back and forth between these servers and other servers/machines at my main site (Site A) just fine. Between these servers and two my other sites (Site B and Site C) however, I cannot ping. Other devices that physically sit in the DMZ can connect to machines at these remote sites.
I thought it was an issue with the ACL so I pulled it and applied an "icmp any any" ACL but this didn't change my ping results. Upon checking the learned routes for my two remote sites I found that neither site had my DMZ subnet. Here's where the confusion comes in at, I have the subnet advertised to both sites. Can someone help with me this?
Sanitized configs will be attached.
Site A Firewall - Cisco ASA 5520
Site A Router - Cisco 2821
Site A to Site B connection: Fiber running EIGRP
Site B Router - Cisco 1841
Site A to Site C connection: MPLS line running BGP
Site C Router - Cisco 1841
Ping back and forth with ACL attached to DMZ interface, pings fail.
Pull ACL off of DMZ interface, pings fail.
Put "icmp any any" ACL on DMZ, pings fail.
Packet tracer ping test comes back successfully, but I never trust packet tracer results.