Re: [Dnsmasq-discuss] dnsmasq returns addresses for non-existent hosts - what have I mis-configured?
On Mon, Nov 09, 2009 at 01:58:25PM +, Chris G wrote: On Sun, Nov 08, 2009 at 10:25:11AM -0500, Perette Barella wrote: It looks like your provider has set up a wildcard A record, which is similar to DNS hijacking as a helpful feature to users who miskey a domain name. It's not isolated to you: mugenshi:etc x10$ host ghijk.isbd.net ghijk.isbd.net has address 195.74.61.93 ghijk.isbd.net mail is handled by 10 mail-in-1.lb.gradwell.net. You could check Gradwell's support pages, but I doubt there is an option to shut it off, since the DNS is published this way. It's a publication problem/feature, not a bug in dnsmasq. I do in fact have the ability to change my domain's zone files. ... and there is what you describe (N.B. this from a web form, not exact zone file syntax) :- * 195.74.61.9386400 A * 10 mail-in-1.lb.gradwell.net. 86400 MX So can I simply delete these two entries? (OK, people mis-typing domain names *might* be affected but that's mostly me so I don't see a big issue there) ... and the answer is yes. I've deleted the wild card lines from the form and now non-existent.isbd.net returns not found, excellent! Thanks for all the help here. -- Chris Green
Re: [Dnsmasq-discuss] dnsmasq returns addresses for non-existent hosts - what have I mis-configured?
On Sun, Nov 08, 2009 at 10:25:11AM -0500, Perette Barella wrote: It looks like your provider has set up a wildcard A record, which is similar to DNS hijacking as a helpful feature to users who miskey a domain name. It's not isolated to you: mugenshi:etc x10$ host ghijk.isbd.net ghijk.isbd.net has address 195.74.61.93 ghijk.isbd.net mail is handled by 10 mail-in-1.lb.gradwell.net. You could check Gradwell's support pages, but I doubt there is an option to shut it off, since the DNS is published this way. It's a publication problem/feature, not a bug in dnsmasq. I do in fact have the ability to change my domain's zone files. ... and there is what you describe (N.B. this from a web form, not exact zone file syntax) :- * 195.74.61.9386400 A * 10 mail-in-1.lb.gradwell.net. 86400 MX So can I simply delete these two entries? (OK, people mis-typing domain names *might* be affected but that's mostly me so I don't see a big issue there) -- Chris Green
[Dnsmasq-discuss] dnsmasq returns addresses for non-existent hosts - what have I mis-configured?
I have dnsmasq working quite happily on a Ubuntu Server 9.10 system providing dns for my small SoHo network. I have just noticed however that if I ask for the address of a non-existent name dnsmasq returns the name of one of my hosting service's machines. It always returns the same address for any non-existent name, e.g.:- chris$ host abcde.isbd.net abcde.isbd.net has address 195.74.61.93 abcde.isbd.net mail is handled by 10 mail-in-1.lb.gradwell.net. chris$ host xyz xyz.isbd.net has address 195.74.61.93 xyz.isbd.net mail is handled by 10 mail-in-1.lb.gradwell.net. chris$ host xyz.isbd.net xyz.isbd.net has address 195.74.61.93 xyz.isbd.net mail is handled by 10 mail-in-1.lb.gradwell.net. I have isbd.net and isbd.co.uk hosted at Gradwell so I do have a connection with them. In fact things are becoming clearer now, 195.74.61.93 is the (quite correct) address returned when you look up isbd.net. So, how can I prevent dnsmasq from returning the parent domain address when I look up anyOldRubbish.isbd.net ? Presumably it can't find the name locally and sends off the request to the upstream name server which (sort of correctly) returns 195.74.61.93. However it means that if I mis-type a name or if one of my machines dies then I may not notice immediately because DNS still succeeds. -- Chris Green
Re: [Dnsmasq-discuss] dnsmasq returns addresses for non-existent hosts - what have I mis-configured?
It looks like your provider has set up a wildcard A record, which is similar to DNS hijacking as a helpful feature to users who miskey a domain name. It's not isolated to you: mugenshi:etc x10$ host ghijk.isbd.net ghijk.isbd.net has address 195.74.61.93 ghijk.isbd.net mail is handled by 10 mail-in-1.lb.gradwell.net. You could check Gradwell's support pages, but I doubt there is an option to shut it off, since the DNS is published this way. It's a publication problem/feature, not a bug in dnsmasq. Dnsmasq does have a a bogus-nxdomain option, which you give some IP addresses and those addresses are translated into NXDOMAIN non- existent domain responses. However, if isbd.net (without leading characters) is actually a useful server to you, this solution is not viable because the valid use shares the same IP as the bogus responses. Perette On 2009年11月08日, at 7:08, Chris G wrote: I have dnsmasq working quite happily on a Ubuntu Server 9.10 system providing dns for my small SoHo network. I have just noticed however that if I ask for the address of a non-existent name dnsmasq returns the name of one of my hosting service's machines. It always returns the same address for any non-existent name, e.g.:- chris$ host abcde.isbd.net abcde.isbd.net has address 195.74.61.93 abcde.isbd.net mail is handled by 10 mail-in-1.lb.gradwell.net. chris$ host xyz xyz.isbd.net has address 195.74.61.93 xyz.isbd.net mail is handled by 10 mail-in-1.lb.gradwell.net. chris$ host xyz.isbd.net xyz.isbd.net has address 195.74.61.93 xyz.isbd.net mail is handled by 10 mail-in-1.lb.gradwell.net. I have isbd.net and isbd.co.uk hosted at Gradwell so I do have a connection with them. In fact things are becoming clearer now, 195.74.61.93 is the (quite correct) address returned when you look up isbd.net. So, how can I prevent dnsmasq from returning the parent domain address when I look up anyOldRubbish.isbd.net ? Presumably it can't find the name locally and sends off the request to the upstream name server which (sort of correctly) returns 195.74.61.93. However it means that if I mis-type a name or if one of my machines dies then I may not notice immediately because DNS still succeeds. -- Chris Green ___ Dnsmasq-discuss mailing list Dnsmasq-discuss@lists.thekelleys.org.uk http://lists.thekelleys.org.uk/mailman/listinfo/dnsmasq-discuss
