A -vs- CNAME

[Cricket Liu]

> I had  an ISP request that a  batch of CNAME's that pointed to one 
> address all be changed to A records pointing to the same IP 
> address.  He  said this would allow his server software to operate  
> "more efficiently."   I  realize that the reverse, changing from a 
> CNAME to an A record can actually cause problems with some  
> operations like sendmail,   but I have not heard that an   A  record   
> could result in more "efficient" server operation than a CNAME.  
> Does anyone have an explanation for how that could be possible?   

Well, if I look up the address of foo.bar.com and foo.bar.com turns out
to be an alias for sna.foo.com, then my name server must look up the
address of sna.foo.com.  Depending on where in the world the foo.com
name servers are, that could take longer than 40 ms.

cricket

Acme Byte & Wire
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