Chaining CNAMEs?

[Mark Andrews]

> Chris De Young wrote:
> > Hi,
> > I was just browsing through the latest edition of the O'Reilly
> > DNS/BIND book, and ran across a bit on pointing a CNAME record at
> > another alias:
> >
> > "The answer is yes: you can chain together CNAME records. The BIND
> > implementation supports it, and the RFCs don't expressly forbid it."
> >
> > The authors go on to recommend against it anyway, but I had always
> > thought that this was actually illegal.  I don't remember now where I
> > had gotten that idea... I think the issue had to do with not being
> > guaranteed that the server would always do the additional processing
> > to ensure that you got to the canonical name at the end of the chain.
> >
> > I guess I've been mistaken?  :-)
> >
> >   
> RFC 1034, Section 3.6.2
> 
> [...]
> 
> Domain names in RRs which point at another name should always point at
> the primary name and not the alias.  This avoids extra indirections in
> accessing information.
> 
> ---
> 
> I've never understood why BIND is so liberal about this, when it's so strict 
> about some many other things. Surely it can't be because of the "should" lang
> uage, can it? Given the time and context in which 1034 was written, that "sho
> uld" is to be treated as a MUST for all practical intents and purposes.

	I suggest that you read the entire paragraph.  Quotes should not
	be taken out of context.
 
> 							- Kevin
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