Re: [Users] Update request to support "Classless IN-ADDR.ARPA delegation"

28 Jan 2014

Hi David,

Thank you for your quick reply.

I'll try to push it to gerrit.

Thank you.

Best Regards,

Mark Kachi

2014-01-28 Yedidyah Bar David <didi@redhat.com>:
...
Hi,
________________________________
From: "Michelle&Judie" <love.cairn@gmail.com>
To: users@ovirt.org
Sent: Tuesday, January 28, 2014 12:32:03 PM
Subject: [Users] Update request to support "Classless IN-ADDR.ARPA
delegation"
Hi guys,
I found a problem on installing server, which has address from small ip
zone, less than a class C.
"engine-setup" checks FQDN resolvability in
"./plugins/ovirt-engine-setup/config/hostname.py".
This program requests forward & reverse query to DNS, and see if it comes
back to host domain name.
Indeed. Note that you can just add a suitable entry to /etc/hosts in most
cases.
But it does not support RFC2317("Classless IN-ADDR.ARPA delegation") type
domain, and fails on FQDN check.
See following URLs for RFC2317 explanation.
http://support.simpledns.com/KB/a146/how-to-sub-delegate-a-reverse-zone.aspx
http://www.rfc-editor.org/rfc/rfc2317.txt
I made patch to "hostname.py" to clear this problem.
Please check following patch, and consider upgrading on the next release.

--- hostname.py.org     2013-12-13 17:22:11.000000000 +0900
+++ hostname.py 2014-01-28 18:01:09.514791351 +0900
@@ -96,15 +96,16 @@
         flags=re.VERBOSE,
         pattern=r"""
             ^
-            (?P<query>\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}).in-addr.arpa.
+            (?P<query>[\w/.-]+)
+            \.
             \s+
             \d+
             \s+
             IN
             \s+
-            PTR
+            (?P<type>(PTR|CNAME))
             \s+
-            (?P<answer>[\w.-]+)
+            (?P<answer>[\w/.-]+)
             \.
             $
         """
@@ -171,11 +172,32 @@
             args=args,
             raiseOnError=False
         )
+        ad=addr.split('.')
+        query="{3}.{2}.{1}.{0}.in-addr.arpa".format(*ad)
         if rc == 0:
             for line in stdout:
                 found = self._DIG_REVLOOKUP_RE.search(line)
-                if found:
-                    names.add(found.group('answer'))
+                if not found:
+                    continue
+                if query != found.group('query'):
+                    continue
+                answer=found.group('answer')
+                if found.group('type') == 'CNAME':
+                    self.logger.debug(
+                        '{query} CNAME to: {answer}'.format(
+                            query=query,
+                            answer=answer,
+                        )
+                    )
+                    query=answer
+                    continue
+                self.logger.debug(
+                    '{query} resolves to: {answer}'.format(
+                        query=query,
+                        answer=answer,
+                    )
+                )
+                names.add(answer)
         return names
def _validateFQDNresolvability(self, fqdn):
Nice Job! Would you like to push it to gerrit yourself for review? See [1]
and [2]
for details.
[1] http://www.ovirt.org/Develop
[2] http://www.ovirt.org/Working_with_oVirt_Gerrit
Thanks, and best regards,
--
Didi

    