https://bugzilla.novell.com/show_bug.cgi?id=447369 Andreas Jaeger changed: What |Removed |Added ---------------------------------------------------------------------------- AssignedTo|bnc-team-screening@forge.provo.novell.com |pbaudis@novell.com -- Configure bugmail: https://bugzilla.novell.com/userprefs.cgi?tab=email ------- You are receiving this mail because: ------- You are on the CC list for the bug.

https://bugzilla.novell.com/show_bug.cgi?id=447369 User mail@steffen-moser.de added comment https://bugzilla.novell.com/show_bug.cgi?id=447369#c2 Steffen Moser changed: What |Removed |Added ---------------------------------------------------------------------------- Status|NEEDINFO |NEW Info Provider|mail@steffen-moser.de | --- Comment #2 from Steffen Moser 2009-01-25 14:12:13 MST --- In the meantime, I think I found an explanationfor this strange behavior... Nevertheless, attached you'll find the requested files. It seems that the problem is caused by the DNS forwarder which is running on my ADSL router (Type: Siemens ADSL SL2-141-I, Firmware version: 3.63m). The openSUSE-11.1 host uses the ADSL router's DNS forwarding services. As soon as I put the IP address of a "real" DNS server (e.g. the one which my ADSL router forwards to) into my "/etc/resolv.conf", everything works like it should. So far, I found out the following: - Preconditions: - Having these entries in "/etc/resolv.conf": | search home.invalid informatik.uni-ulm.de egu.schule.ulm.de | nameserver 192.168.1.1 - This means: Using my ADSL router as a DNS forwarder - Behavior: - When typing "host www" (a host called "www" is existent within both domains, "informatik.uni-ulm.de" and "egu.schule.ulm.de", but not within "home.invalid"), the local resolver asks the ADSL router for the IP address of "www.home.invalid" as "home.invalid" is the first search domain in "/etc/resolv.conf". "www.home.invalid" does, as stated, not exist. - According to "wireshark", the ADSL router answers with the following flags in its DNS query response: Flags: 0x8100 (Standard query response, No error) 1... .... .... .... = Response: Message is a response .000 0... .... .... = Opcode: Standard query (0) .... .0.. .... .... = Authoritative: Server is not an authority for domain .... ..0. .... .... = Truncated: Message is not truncated .... ...1 .... .... = Recursion desired: Do query recursively .... .... 0... .... = Recursion available: Server can't do recursive queries .... .... .0.. .... = Z: reserved (0) .... .... ..0. .... = Answer authenticated: Answer/authority portion was not authenticated by the server .... .... .... 0000 = Reply code: No error (0) [...] - Of course, the DNS forwarder on the ADSL router doesn't deliver an IP address for the queried host name (as such one doesn't exist). - After then, the resolver on the host (openSUSE 11.1, for example) doesn't continue asking the DNS forwarder for "www" within the other search domains ("www.egu.schule.ulm.de" and "www.informatik.uni-ulm.de"). Perhaps the host thinks that the answer was "okay" ("No error"). That means in concrete: The host does ask for an "AAAA" and "MX" entry of "www.home.invalid" (most probably because the "host" command likes to list these, too), but the second and the third search domains are never used! The resolver in SuSE 10.0, for example, behaves different. That one asked for "www.egu.schule.ulm.de" - which can be resolved successfully. After then I tried the following: - Preconditions: - Having these entries in "/etc/resolv.conf": | search home.invalid informatik.uni-ulm.de egu.schule.ulm.de | nameserver 217.237.150.188 - This means: I am using my ISP's DNS to resolve host names (and not the ADSL router's DNS forwarder) this time. By the way: "217.237.150.188" is exactly the nameserver which my ADSL router forwards its queries to (the one which is assigned automatically when connecting via PPPoE to my ISP). - Different Behavior: - When typing "host www", the local resolver asks "217.237.150.188" for the IP address of "www.home.invalid" as "home.invalid" is the first search domain in "/etc/resolv.conf". "www.home.invalid" does, as stated, still not exist. - According to "wireshark", "217.237.150.188" answers with the following flags in its DNS query response: Flags: 0x8183 (Standard query response, No such name) 1... .... .... .... = Response: Message is a response .000 0... .... .... = Opcode: Standard query (0) .... .0.. .... .... = Authoritative: Server is not an authority for domain .... ..0. .... .... = Truncated: Message is not truncated .... ...1 .... .... = Recursion desired: Do query recursively .... .... 1... .... = Recursion available: Server can do recursive queries .... .... .0.. .... = Z: reserved (0) .... .... ..0. .... = Answer authenticated: Answer/authority portion was not authenticated by the server .... .... .... 0011 = Reply code: No such name (3) As you can see, the answer for exactly the same query looks totally different when asking my ISP's DNS server instead of the DNS forwarder served by my ADSL router. My ISP's DNS server states explicitly that the host name does not exist. After then, openSUSE-11.1's resolver looks into the other search domains (which is successful, of course). Results: - I suppose that my ADSL router's DNS forwarder behaves in a wrong way (I haven't looked into the DNS RFCs to make sure that this assumption is right): It says "No error" (instead of "No such name") if a given host name is not resolvable. - But it also seems that the resolver in former versions of SUSE Linux behaved in a different way. At least SUSE-10.0 started the searches according the "search" line in "/etc/resolv.conf" even when asking my (most probably buggy) DNS forwarder that runs on my ADSL router. This behavior has changed somewhere between SUSE 10.0 and openSUSE 10.3. Therefore I thought it's an bug in openSUSE, but it seems that the problem is my ADSL router, or especially the "dproxy" service which is running on it. -- Configure bugmail: https://bugzilla.novell.com/userprefs.cgi?tab=email ------- You are receiving this mail because: ------- You are on the CC list for the bug.

https://bugzilla.novell.com/show_bug.cgi?id=447369 User mail@steffen-moser.de added comment https://bugzilla.novell.com/show_bug.cgi?id=447369#c4 --- Comment #4 from Steffen Moser 2009-01-25 14:17:37 MST --- Created an attachment (id=267521) --> (https://bugzilla.novell.com/attachment.cgi?id=267521) File "/etc/host.conf" -- Configure bugmail: https://bugzilla.novell.com/userprefs.cgi?tab=email ------- You are receiving this mail because: ------- You are on the CC list for the bug.

https://bugzilla.novell.com/show_bug.cgi?id=447369 User mail@steffen-moser.de added comment https://bugzilla.novell.com/show_bug.cgi?id=447369#c5 --- Comment #5 from Steffen Moser 2009-01-25 14:18:49 MST --- Created an attachment (id=267523) --> (https://bugzilla.novell.com/attachment.cgi?id=267523) File "/etc/nsswitch.conf" -- Configure bugmail: https://bugzilla.novell.com/userprefs.cgi?tab=email ------- You are receiving this mail because: ------- You are on the CC list for the bug.