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I have a domain purchased from - I am using heroku for hosting a rails app for this domain. Today I tried to setup DNS for this domain. The top level domain works fine but when I try to setup CNAME for "www", I get the following error :

ubuntu:~/rails_projects/socal$ host
Host not found: 3(NXDOMAIN)
('xyz' is just for example)

My CNAME settings in looks like :

Record Type     Record Host     Record Answer          TTL  
CNAME        1800     

This is as per the instructions on domains Not sure what could be wrong with my DNS settings

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up vote 0 down vote accepted

I highly suggest using a A record for www ,as a Cname will cause 2 lookups at the server doubling the load. Cnames were designed fir when you don't control the other domain, An A record is much more suited for this

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I cant create www A record with - I get 'Invalid character used for record answer' I will try creating with ip – user70692 Feb 14 '11 at 13:14
Created A record for all heroku ips - still same error : – user70692 Feb 14 '11 at 13:17
any time lag before the changes are reflected ? – user70692 Feb 14 '11 at 13:38
If you setup another record it should ask the server as it hasn't cached it yet. – Jacob Feb 14 '11 at 13:39
does heroku assign you a IP or a hostname? – Jacob Feb 14 '11 at 13:41

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