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Is there a way to override & increase the received TTL from an upstream DNS server?

Is there a configuration parameter in dnsmasq for this?

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2 Answers 2

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Basing my answer on your comments to Gareth (which really should be incorporated into your question), I would say that the most likely causes of your problem are:

  1. You're not actually using the cache you think you are, or
  2. The TTLs for the site you're visiting are set quite low, normally for a reason, and there's nothing reasonable you can do about it (except perhaps identify the root cause of the frequent DNS lookup failures and fix them yourself (if, for example, the cause was a congested local Internet connection) or petition the entity responsible to have them fixed (if, for example, the problem was that the zone is delegated to a flaky authoritative DNS server))
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Do you mean the TTL for a negative response from an upstream server ? That's controlled by the --neg-ttl parameter:

--neg-ttl= Negative replies from upstream servers normally contain time-to-live information in SOA records which dnsmasq uses for caching. If the replies from upstream servers omit this information, dnsmasq does not cache the reply. This option gives a default value for time-to-live (in seconds) which dnsmasq uses to cache negative replies even in the absence of an SOA record.

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hmmm... I am not sure. Let me give you an example of what I am trying to do: There is a good site I visit often (e.g. stackoverflow.com) and my Ubuntu desktop keeps on waiting for DNS replies too many times. I have installed dnsmasq in hopes of mitigating this problem to no avail. I do not know if their DNS server is properly set or I am missing/messed up something. –  jldupont Nov 21 '09 at 18:36
    
The use case I'm currently looking at with regards to this questing is uptime monitoring on locations with a dynamic IP address using a dynamic IP DNS service. I'm nearly exceeding the allotted monthly DNS queries. The TTL is set to 60 for good reason but I'd like to override this value for one specific domain to reduce my queries. –  freb Oct 11 '13 at 16:38

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