Dataflow Process - Domain-Name-System-Resolution-Process-for-Named-Resources/Dataflow-Process

Domain Name System Resolution Process for Named Resources
ft:locale
en-US
ft:sourceName
Paligo_Prod
Document Type
Concept

  1. Domain Name System (DNS) resolution:

    1. pc1 sends a DNS request to the NCX Site 1 router (source 192.168.1.5 | destination 192.168.1.1).

    2. NCX Site 1 router:

      1. Identifies the DNS server (100.127.255.254 - configured by Secure Connect template configuration).

      2. The NCX Site 1 router performs a route lookup in the GRE table.

    3. The NCX Site 1 router proxies the DNS request and forwards it to the NetCloud Exchange Service Gateway (source 192.168.1.1 | destination 100.127.255.254).

    4. The NCX Service Gateway forwards the DNS request to the DNS server or servers, configured at the network level.

    5. The DNS server or servers respond to the DNS query (server.dc.ncx == 10.0.0.254).

    6. NCX Service Gateway processing:

      1. Prime NAT <> underlay IP address mapping (10.0.0.254 == 100.64.0.254)

    7. The NCX Service Gateway forwards the DNS response to the NCX Site 1 router (server.dc.ncx == 100.64.0.254).

    8. The NCX Site 1 router forwards the DNS response to pc1.

  2. IP address traffic:

    1. pc1 generates an Internet Control Message Protocol (ICMP) request packet and sends it to the NCX Site 1 router (source 192.168.1.5 | destination 100.64.0.254).

    2. The NCX Site 1 router performs a route lookup in the GRE table.

    3. The NCX Site 1 router forwards the ICMP packet to the NCX Service Gateway (source 192.168.1.5 | destination 100.64.0.254).

    4. NCX Service Gateway processing:

      1. Network address translation (NAT)/XLATE to prime NAT range:

        • original source 192.168.1.5 > new source 100.64.0.5

      2. NAT/XLATE to lan0 interface IP address:

        • original source 100.64.0.5 > new source 10.0.0.1

      3. NAT/XLATE destination IP address to underlay IP address:

        • Original destination 100.64.0.254 > new destination 10.0.0.254

      4. Flow match/creation

    5. The NCX Service Gateway forwards the xlated ICMP packet out the lan0 interface (source 10.0.0.1 | destination 10.0.0.254).

    6. ICMP responds from 10.0.0.254 to the NCX Service Gateway (source 10.0.0.254 | destination 10.0.0.1).

    7. The NCX Service Gateway forwards the ICMP response to the NCX Site 1 router (source 100.64.0.254 | destination 192.168.1.5).

    8. The NCX Site 1 router forwards the ICMP response to pc1 (source 100.64.0.254 | destination 192.168.1.5).