[CentOS] very strange

i have 2 servers in a datacenter and each of them has 2 virtual machines one is linux the other is windows of wirtual machines. when i want to transfer my ip addresses between theese servers , for ex: let me say main server 1' guest windows : A main server 1' guest CentOs: B main server 2' guest windows : C main server 1' guest CentOs: D

when i handle an ip of any computers ip in network from A or C it directly handles, no matter where the ip routed from cisco router :D but when i want to handle any computers ip in network from B or D it never get the ip from other source :D

how this could happen :)