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How to determine DNS TTL Remaining
I am wondering if there is a way to determine how long a cached DNS record has been on a DNS server and subsequently how long it will be before the record expires and the DNS server will do a look up to the domains DNS servers.
For example, if I do not have direct access to my ISPs DNS server is there away I can do a query against that server via nslookup for example, and determine how long it will be before that DNS server will dump www.dogpile.com from its cache and requery the authoritative DNS server for dogpile.com. I am not looking simply for the TTL as I can get that. What I want I am looking for is how many seconds to go before the TTL expires on the query/caching server.
For example, if I do not have direct access to my ISPs DNS server is there away I can do a query against that server via nslookup for example, and determine how long it will be before that DNS server will dump www.dogpile.com from its cache and requery the authoritative DNS server for dogpile.com. I am not looking simply for the TTL as I can get that. What I want I am looking for is how many seconds to go before the TTL expires on the query/caching server.
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For others, the syntax is:
nslookup -debug - nameserver
;where name server is the IP or hostname of the DNS server.