[dns-operations] CNAME points to itself

[fujiwara at jprs.co.jp]

> From: yhpeng at orange.fr
> I have found that CNAME can be setup to point to itself (at least in
> BIND9 it can be).
> 
> www.itest.com.          300     IN      CNAME   www.itest.com.
> 
> should this be disabled?

Read RFC 1034 Section 3.6.2. Aliases and canonical names

| domain software should not fail when presented with CNAME
| chains or loops; CNAME chains should be followed and CNAME loops
| signalled as an error.

--
Kazunori Fujiwara, JPRS <fujiwara at jprs.co.jp>