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Anas_Hijjawi_44's avatar
Anas_Hijjawi_44
Icon for Nimbostratus rankNimbostratus
Apr 23, 2013

GTM: If main site went down, will the LDNS resolve negative queries from its cache

In GTM deployment, if my main "primary" site went down, will the end users Local DNS resolve negative queries from its old cache, if so how F5 GTM will cover this issue  
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Hamish's avatar
Hamish
Icon for Cirrocumulus rankCirrocumulus
Apr 27, 2013
LDNS will service from it's cache for as long as the TTL is set. You set the TTL yourself, so it's up to you.

 

 

However the whole idea of GTM is to NOT cache too much... You don't want LDNS to cache when GTM wants to resolve to a different address... The TTL should be set to the time you can handle clients tring to contact a down host (i.e. If SiteA goes down 2 seconds after you've given SiteA address to CustomerA, you set the TTL to the amount of time you can live with CustomerA not being able to work...

 

 

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