IT 3100 : Systems Design and Administration I

DNS Troubleshooting


SOA Fields

What is SOA? (Start of Authority)

    @       IN      SOA     ns1.thegummibear.com. root.ns1.thegummibear.com. (

SOA Fields

    2017012001      ; Serial
    3600   ; Refresh
    300   ; Retry

SOA Fields

    241920  ; Expire
    60)   ; Negative Cache TTL

DNS Debugging

Steps (order matters)


dig

Examples:


Master Troubleshooting


Slave Troubleshooting


Delegation (Recursive Lookups)

We haven’t enabled this fully yet, but


Misc

After making changes on registrar to point to your nameservers, may have to wait for cache to expire before changes will appear.

Do digs from top down to troubleshoot.