learning CCENT and curious how does ping resolve host names on the internet

gbdavidxgbdavidx Member Posts: 840
learning CCENT and curious how does ping resolve host names on the internet

so everyone knows you have computer A with IP how does it even begin to find the end host?

do all the routers on the internet (ISP networks) have all routes?

newb question


  • SteveO86SteveO86 Member Posts: 1,423
    When your PC performs a ping, or you initiate a ping from the router the name is resolved through DNS, the PC or router needs to be configured with a DNS server to forward the request to.

    That host name is sent from the end device to the DNS server the DNS server resolves it and sends the IP address back to the end-device. That IP address is used as the target for the ping

    This might help
    HowStuffWorks "How Domain Name Servers Work"
    My Networking blog
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    Currently Studying: CCNP: Wireless - IUWMS
  • gbdavidxgbdavidx Member Posts: 840
    I may be thinking to hard, how does it find the dns server of the name though?
  • YFZbluYFZblu Member Posts: 1,462 ■■■■■■■■□□
    ICMP does not resolve hostname to IP address; your computer does that before sending the ping. Your DNS server is configured on the client beforehand - If you're at home, by default you are likely configured to use your ISP's DNS server.
  • lsud00dlsud00d Member Posts: 1,571
    Requests are forwarded on until someone can provide an authoritative response.
  • TurK-FXTurK-FX Member Posts: 174
    If it is not configured, your router dynamically gets the DNS server info from ISP. As you go along with your study, it will make better sense. You need to get it cold with ARP, ping, DNS, DHCP processes to pas ICND1.
    WGU classes: Transferred -> AGC1, CLC1, TBP1, CJC1, BVC1, C278, CRV1, IWC1, IWT1, C246, C247, C132, C164, INC1, C277. Appealed -> WFV1 and C393.
    What is Left to take - > EUP1, EUC1, C220, C221, BNC1, GC1, C299, CTV1, DJV1, DHV1, CUV1, CJV1, TPV1, C394
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  • mdominomdomino Member Posts: 81 ■■□□□□□□□□
    When you "ping google.com"
    1. Your computer realizes this is a name and not an IP, so it needs to find out who owns it
    2. Your computer queries the DNS server configured (your ISP's DNS server, probably) and receives an IP address that correlates to that domain name
    3. Now your computer has enough information to send a packet!
    4. Your computer sees that the IP for google.com is NOT on its subnet, so it forwards it to your default gateway (your cable modem/router/ADSL modem etc)
    5. The router sees that it doesn't know a route to the IP, so it sends it out its default route to the internet (your default gateway)
    6. From here, the routers each route the packet according to their routing tables until it makes it to your host
    7. Now, it works its way back in reverse!

    Hope that clarifies
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