1. I have 3 testing machines in the Active Directory Environment DC1, DC2, DC3)
2. I created 2 subnet ( i use the subnet mask: 255.255.255.192)
3. The DC1 is a domain controller(which domain is domain1), DC3 is a replica domain controllerof domain1, and DC2 is a child domain of domain1 which i called child.domain1.
4. The network ID is 204.127.60; the ist subnet is in this range: 22.214.171.124-126; the 2nd subnet is in the range of 126.96.36.199-190
5. I assume DC1 is in the first subnet, DC2 as a ROUTER, and DC3 is in the 2nd subnet.
6. DC1: i) Domain: domain1, ii)IP: 188.8.131.52, iii) SM: 255.255.255.192, iv)Default Gateway: 184.108.40.206, v) DNS: 220.127.116.11
7. DC2: i) There are 2 NIC, ii) the ist NIC: a1) IP: 18.104.22.168, a2)the SM: 255.255.255.192, a3) Default Gateway: Blank, a4) DNS: 22.214.171.124, iii) the 2nd NIC: a1) IP: 126.96.36.199, a2) the SM:same, a3)DG: Blank, a4)DNS: 188.8.131.52 (Same as IP address of DC1)
8. DC3: i)This is replica domain controller of domain1, ii)IP: 184.108.40.206, iii)SM:255.255.255.192, iv)Default Gateway: 220.127.116.11, v)DNS: 18.104.22.168 (Same as IP address of DC1).
9. Problem: i) When I ping DC3 from DC1; the message: "request time out", ii) When i ping DC1 from DC3; message: "Unknown host dc1", iii) Others are good (i can ping fr DC2 to DC1 &DC3 successfully, i can ping FR DC1 to DC2 successfully, I can ping fr DC3 to DC2 successfully)
10. Is it DNS problem ? Somebody knows the solution ?
11. Thank you.