beer9
asked on
How the 'forward first' behave when recursion is enabled in DNS?
Hello,
I have below config named config
options {
recursion yes;
allow-recursion {"internals";};
directory "/var/named";
forward first;
forwarders {
10.10.10.20;
10.10.10.30;
};
};
Here recursion is enabled and forward is configured as first. Now, what happens when a resolver client send a query with RD (recursive desired) flag on?
My understanding it below:
1. First, it's will search in it's cache and if it's available then it will return the answer to resolver client
2. If it's not in cache then it will forward the query to forwarders DNS server and once it's found the answer then return the answer to resolver client.
3. If it's not in cache and forwarders DNS server doesn't answer the query then it will do the recursive query himself and go through all the way from root to g-tld to authorized name server and get the answer then return the answer to resolver client.
Please let me know if my understanding for this name resolution workflow looks good?
Thanks!
I have below config named config
options {
recursion yes;
allow-recursion {"internals";};
directory "/var/named";
forward first;
forwarders {
10.10.10.20;
10.10.10.30;
};
};
Here recursion is enabled and forward is configured as first. Now, what happens when a resolver client send a query with RD (recursive desired) flag on?
My understanding it below:
1. First, it's will search in it's cache and if it's available then it will return the answer to resolver client
2. If it's not in cache then it will forward the query to forwarders DNS server and once it's found the answer then return the answer to resolver client.
3. If it's not in cache and forwarders DNS server doesn't answer the query then it will do the recursive query himself and go through all the way from root to g-tld to authorized name server and get the answer then return the answer to resolver client.
Please let me know if my understanding for this name resolution workflow looks good?
Thanks!
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