I believe that the easiest answer for the first question is "No, You have "A" for this", but I accidentally setup some subdomain using CNAME pointing to ip address and it worked on few computers in my office. I wonder how it was possible?
Now, when I'm checking it from home I have following error:
beast:~ viroos$ host somesubdomain.somedomain.com Host somesubdomain.somedomain.com not found: 3(NXDOMAIN)
I'm 100% it used to work at my office (currently it looks like it doesn't, but I'm checking it on different machine). Therefore I'm not 100% if it worked due to some special network setup or because I tested it just after adding DNS entry.
I know this story sounds, a little crazy/incredibly, but can someone help me solve this puzzle.
//edit: I'm adding dig output
; <<>> DiG 9.6-ESV-R4-P3 <<>> somesubdomain.somedomain.com ;; global options: +cmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NXDOMAIN, id: 60224 ;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 1, ADDITIONAL: 0 ;; QUESTION SECTION: ;somesubdomain.somedomain.com. IN A ;; ANSWER SECTION: somesubdomain.somedomain.com. 67 IN CNAME xxx.xxx.xxx.xx1. ;; AUTHORITY SECTION: . 1800 IN SOA a.root-servers.net. nstld.verisign-grs.com. 2012040901 1800 900 604800 86400 ;; Query time: 72 msec ;; SERVER: 220.127.116.11#53(18.104.22.168) ;; WHEN: Tue Apr 10 00:11:01 2012 ;; MSG SIZE rcvd: 136