30 April 2010
Improving your resolv.conf file
The resolver can load up to 3 name servers. If your server needs to find the mx record of gmail.com, it will first need to resolve gmail.com locally.
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using a resolver from resolv.conf
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dig @8.8.8.8 gmail.com -t mx +short
result: alt1.gmail-smtp-in.l.google.com
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connect to alt1.gmail-smtp-in.l.google.com
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dig @8.8.4.4 alt1.gmail-smtp-in.l.google.com +short
result: 209.85.227.27
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connect to 209.85.227.27:25
Optimized resolv.conf
nameserver 8.8.8.8
nameserver 8.8.4.4
nameserver 4.2.2.2
option rotate
option timeout:1
option rotate - load balance the queries across the 3 listed servers
option timeout:1 - sets the lookup timeout to 1 sec (default 5s)
