Package: libc6 Version: 2.3.2.ds1-22sarge3 Severity: normal [this problem exists in libc6 all through unstable]
I set up our internal DNS server to answer a query for gluck.mydebian.org with a CNAME for gluck.debian.org. However, I cannot access it: piper:~> host gluck.mydebian.org gluck.mydebian.org CNAME gluck.debian.org gluck.debian.org A 192.25.206.10 piper:~> ping gluck.mydebian.org ping: unknown host gluck.mydebian.org The reason seems to be that the CNAME response does not contain the A record, and the resolver doesn't bother to go out to resolve the name pointed to by the CNAME. This is what happens if I resolve a CNAME outside of my own network, so my DNS server is caching/recursing only: 192.168.20.21 -> 192.168.20.1 DNS Standard query A ftp.ch.debian.org 192.168.20.1 -> 192.168.20.21 DNS Standard query response CNAME debian.ethz.ch A 129.132.86.196 Notice how the answer includes the A record. This is what happens if the CNAME is resolved internally, but the A record has to be resolved externally (or the other way around, CNAME externally and A record internally): 192.168.20.21 -> 192.168.20.1 DNS Standard query A gluck.mydebian.org 192.168.20.1 -> 192.168.20.21 DNS Standard query response CNAME gluck.debian.org Note the lack of A record. Arguably, my DNS server (maradns) is at fault here, for it fails to do the work the way one might expect. But in either case, the local resolver *should* be able to cope with the situation, just like the `host' utility: 192.168.20.21 -> 192.168.20.1 DNS Standard query A gluck.mydebian.org 192.168.20.1 -> 192.168.20.21 DNS Standard query response CNAME gluck.debian.org 192.168.20.21 -> 192.168.20.1 DNS Standard query A gluck.debian.org 192.168.20.1 -> 192.168.20.21 DNS Standard query response A 192.25.206.10 ... which means that if all it gets is a CNAME in response to request of (almost) any type, it should repeat the request for the same type with the new name, IMHO. -- Please do not send copies of list mail to me; I read the list! .''`. martin f. krafft <[EMAIL PROTECTED]> : :' : proud Debian developer and author: http://debiansystem.info `. `'` `- Debian - when you have better things to do than fixing a system
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