Re: forwarding zone setup from a BIND slave (without recursion?)
Mark Andrews wrote: > > On 8 Apr 2021, at 00:37, Tony Finch wrote: > > > > Forward zones require the upstream server to be recursive too. > > More correctly, the upstream server has to serve the entire namespace being > forwarded if it does not off recursion to the client for forwarding to > work. I thought forwarding expected the target server to resolve CNAMEs? If so, any out-of-zone CNAMEs in the target namespace would cause problems. Tony. -- f.anthony.n.finchhttps://dotat.at/ Cape Wrath to Rattray Head including Orkney: Southwesterly 6 to gale 8, occasionally 5 at first in east, then veering westerly or northwesterly 7 to severe gale 9 later. Moderate or rough, becoming very rough or high in north. Rain at times, squally snow showers later. Moderate or good, occasionally very poor later. ___ Please visit https://lists.isc.org/mailman/listinfo/bind-users to unsubscribe from this list ISC funds the development of this software with paid support subscriptions. Contact us at https://www.isc.org/contact/ for more information. bind-users mailing list bind-users@lists.isc.org https://lists.isc.org/mailman/listinfo/bind-users
Re: forwarding zone setup from a BIND slave (without recursion?)
Chuck, Tony, Thank you all for sharing the ideas.. very much appreciated. Thank you Kind Regards, Ravi Kota On Wed, Apr 7, 2021 at 7:25 PM wrote: > Send bind-users mailing list submissions to > bind-users@lists.isc.org > > To subscribe or unsubscribe via the World Wide Web, visit > https://lists.isc.org/mailman/listinfo/bind-users > or, via email, send a message with subject or body 'help' to > bind-users-requ...@lists.isc.org > > You can reach the person managing the list at > bind-users-ow...@lists.isc.org > > When replying, please edit your Subject line so it is more specific > than "Re: Contents of bind-users digest..." > > > Today's Topics: > >1. Re: forwarding zone setup from a BIND slave (without > recursion?) (Chuck Aurora) >2. Re: forwarding zone setup from a BIND slave (without > recursion?) (Tony Finch) >3. Re: rndc stops listening (John Thurston) >4. Re: rndc stops listening (Ond?ej Sur?) >5. Re: forwarding zone setup from a BIND slave (without > recursion?) (Mark Andrews) > > > -- > > Message: 1 > Date: Wed, 07 Apr 2021 07:53:01 -0500 > From: Chuck Aurora > To: bind-users@lists.isc.org > Subject: Re: forwarding zone setup from a BIND slave (without > recursion?) > Message-ID: > Content-Type: text/plain; charset=US-ASCII; format=flowed > > On 2021-04-07 03:59, Marki wrote: > > To elaborate a little bit on that... Indeed that is how it works, > > unfortunately. When you start using forwarders or stubs, recursion > > needs to be enabled because you're no longer looking for your own > > authoritative data only. > > A stub or static-stub zone would not require recursion. In that case > named is asking for authoritative data from upstream. But type > forward zones indeed cannot work if recursion is disabled. > > > What I've learned from this list is that you should split > > authoritative and recursive service. > > I would suggest that as a general best practice, but not an absolute > one. There's nothing wrong with having internal-only authoritative > zones on your recursive resolver. The potential problem comes when > you're a globally-published NS for your zones; having recursion > enabled can make you vulnerable to more possible attacks. > > I'd say it depends more who/what you are. Small-timers are not at so > much risk for this than large sites and ISPs. But there too, the > paranoid would go for two instances of named, authoritative and > recursive, on a small hosted server even where it's only offering > recursion to itself. > > > May I ask what is the reasoning behind your current setup (pointing > > your users to the non-recursive service)? What would you like to > > achieve? What would you like to prevent? > > Agreed, that is strange. It does not seem that an authoritative-only > named can be very useful for end users. > > > -- > > Message: 2 > Date: Wed, 7 Apr 2021 15:37:33 +0100 > From: Tony Finch > To: Chuck Aurora > Cc: bind-users@lists.isc.org > Subject: Re: forwarding zone setup from a BIND slave (without > recursion?) > Message-ID: > Content-Type: text/plain; charset=US-ASCII > > Chuck Aurora wrote: > > > > A stub or static-stub zone would not require recursion. In that case > > named is asking for authoritative data from upstream. But type > > forward zones indeed cannot work if recursion is disabled. > > Be careful in this kind of situation to be very clear about which client > or server is doing what: in this case, it isn't clear what doesn't require > recursion for stub or static stub. > > All three types of zone configuration (stub, static stub, and forward) > are only useful on a server that is providing recursive service. > > Forward zones require the upstream server to be recursive too. > > Stub and static-stub expect the upstream server to be authoritative; > the stub server list is a hint that gets replaced by the authoritative > server list from the zone (a bit like the root hints) whereas static-stub > only uses the configured upstream servers. > > > > What I've learned from this list is that you should split > > > authoritative and recursive service. > > > > I would suggest that as a general best practice, but not an absolute > > one. There's nothing wrong with having internal-only authoritative > > zones on your recursive resolver. The potential problem comes when > > you're a globally-published NS for your zones; having recursion > > enabled can make you vulnerable to more possible attacks. > > Right: the rule is that authoritative servers listed as targets of NS > records should be authoritative-only; it's OK if recursive servers have > authoritative copies of zones: it can make them more resilient to outages, > though it does slightly weird things to DNSSEC validation. > > Tony. > -- > f.anthony.n.finchhttps://dotat.at/ > Whitby to Gibraltar Point: Northwest 4
Re: forwarding zone setup from a BIND slave (without recursion?)
ect: Re: forwarding zone setup from a BIND slave (without > recursion?) > Message-ID: > Content-Type: text/plain; charset="utf-8"; Format="flowed" > > Hello, > > On 4/7/2021 10:35 AM, Matus UHLAR - fantomas wrote: > > On 06.04.21 22:47, RK K wrote: > >> In this scenario, in-order for the secondary server to forward the DNS > >> query to an external DNS server, is it required to enable the > >> recursion in > >> the global options on the secondary servers? > > > > yes. > > To elaborate a little bit on that... Indeed that is how it works, > unfortunately. When you start using forwarders or stubs, recursion needs > to be enabled because you're no longer looking for your own > authoritative data only. > > What I've learned from this list is that you should split authoritative > and recursive service. > > In other words, you need two types of servers: > > 1) A non-recursive one in the backend containing your authoritative > zones only. This can be a hidden master setup, somewhat like what you > are using now. > > 2) The one your users access has recursion enabled, and contains stubs > to the authoritative service. Obviously, it can also contain stubs (or > forwarders) to anywhere else. At the same time it is performing full > recursive service unless you take authority for the root zone. > > May I ask what is the reasoning behind your current setup (pointing your > users to the non-recursive service)? What would you like to achieve? > What would you like to prevent? > > Bye, > > Marki > > -- next part -- > An HTML attachment was scrubbed... > URL: < > https://lists.isc.org/pipermail/bind-users/attachments/20210407/b96c3543/attachment-0001.htm > > > > -- > > Subject: Digest Footer > > ___ > ISC funds the development of this software with paid support > subscriptions. Contact us at https://www.isc.org/contact/ for more > information. > > bind-users mailing list > bind-users@lists.isc.org > https://lists.isc.org/mailman/listinfo/bind-users > > > -- > > End of bind-users Digest, Vol 3678, Issue 1 > *** > ___ Please visit https://lists.isc.org/mailman/listinfo/bind-users to unsubscribe from this list ISC funds the development of this software with paid support subscriptions. Contact us at https://www.isc.org/contact/ for more information. bind-users mailing list bind-users@lists.isc.org https://lists.isc.org/mailman/listinfo/bind-users
Re: forwarding zone setup from a BIND slave (without recursion?)
> On 8 Apr 2021, at 00:37, Tony Finch wrote: > > Chuck Aurora wrote: >> >> A stub or static-stub zone would not require recursion. In that case >> named is asking for authoritative data from upstream. But type >> forward zones indeed cannot work if recursion is disabled. > > Be careful in this kind of situation to be very clear about which client > or server is doing what: in this case, it isn't clear what doesn't require > recursion for stub or static stub. > > All three types of zone configuration (stub, static stub, and forward) > are only useful on a server that is providing recursive service. > > Forward zones require the upstream server to be recursive too. More correctly, the upstream server has to serve the entire namespace being forwarded if it does not off recursion to the client for forwarding to work. > Stub and static-stub expect the upstream server to be authoritative; > the stub server list is a hint that gets replaced by the authoritative > server list from the zone (a bit like the root hints) whereas static-stub > only uses the configured upstream servers. > >>> What I've learned from this list is that you should split >>> authoritative and recursive service. >> >> I would suggest that as a general best practice, but not an absolute >> one. There's nothing wrong with having internal-only authoritative >> zones on your recursive resolver. The potential problem comes when >> you're a globally-published NS for your zones; having recursion >> enabled can make you vulnerable to more possible attacks. > > Right: the rule is that authoritative servers listed as targets of NS > records should be authoritative-only; it's OK if recursive servers have > authoritative copies of zones: it can make them more resilient to outages, > though it does slightly weird things to DNSSEC validation. > > Tony. > -- > f.anthony.n.finchhttps://dotat.at/ > Whitby to Gibraltar Point: Northwest 4 to 6 becoming variable 2 to 4, > then southwest 4 to 6 later. Very rough at first in north, otherwise > moderate or rough. Snow showers, then rain for a time later. Good, > occasionally very poor at first. > > ___ > Please visit https://lists.isc.org/mailman/listinfo/bind-users to unsubscribe > from this list > > ISC funds the development of this software with paid support subscriptions. > Contact us at https://www.isc.org/contact/ for more information. > > > bind-users mailing list > bind-users@lists.isc.org > https://lists.isc.org/mailman/listinfo/bind-users -- Mark Andrews, ISC 1 Seymour St., Dundas Valley, NSW 2117, Australia PHONE: +61 2 9871 4742 INTERNET: ma...@isc.org ___ Please visit https://lists.isc.org/mailman/listinfo/bind-users to unsubscribe from this list ISC funds the development of this software with paid support subscriptions. Contact us at https://www.isc.org/contact/ for more information. bind-users mailing list bind-users@lists.isc.org https://lists.isc.org/mailman/listinfo/bind-users
Re: rndc stops listening
John, please report the issue to the ISC GitLab. Thanks, -- Ondřej Surý — ISC (He/Him) My working hours and your working hours may be different. Please do not feel obligated to reply outside your normal working hours. > On 7. 4. 2021, at 19:32, John Thurston wrote: > > I now see this same behavior running BIND 9.16.12 on Ubuntu > > I have never seen it on my instances running 9.11.x on Centos > > I'd sure like to figure out why (or even when) it stops listening on port > 953. Does anyone have any suggestions? > > -- > Do things because you should, not just because you can. > > John Thurston907-465-8591 > john.thurs...@alaska.gov > Department of Administration > State of Alaska > >> On 12/11/2020 11:13 AM, John Thurston wrote: >> Running BIND 9.16.9 on CentOS 8 >> I have the following in my .conf >>> controls { >>> inet 127.0.0.1 port 953 >>> allow { 127.0.0.1; } keys { "mykey"; }; >>> inet 10.2.0.1 port 953 >>> allow { 10.2.3.3; 10.2.4.3; } >>> keys { "threekey"; "fourkey"; }; >>> }; >> And I normally can see the named process is listening on tcp:953 on both >> 127.0.0.1 and 10.2.0.1. But sometimes later, I find it listening only on >> 127.0.0.1. If I do an 'rndc reconfig', it starts listening again on both >> addresses. Normal DNS service has continued uninterrupted. >> I can't find footprints left from anything falling down. I'd could just >> install a watchdog to 'reconfig' whenever port 953 stops answering, but I'd >> rather figure out why it is stopping and correct the problem. To do that, I >> need more information. >> Am I not looking in the correct log? >> Do I need to crank up the logging level for something? >> If so, for what? and how high? > ___ > Please visit https://lists.isc.org/mailman/listinfo/bind-users to unsubscribe > from this list > > ISC funds the development of this software with paid support subscriptions. > Contact us at https://www.isc.org/contact/ for more information. > > > bind-users mailing list > bind-users@lists.isc.org > https://lists.isc.org/mailman/listinfo/bind-users ___ Please visit https://lists.isc.org/mailman/listinfo/bind-users to unsubscribe from this list ISC funds the development of this software with paid support subscriptions. Contact us at https://www.isc.org/contact/ for more information. bind-users mailing list bind-users@lists.isc.org https://lists.isc.org/mailman/listinfo/bind-users
Re: rndc stops listening
I now see this same behavior running BIND 9.16.12 on Ubuntu I have never seen it on my instances running 9.11.x on Centos I'd sure like to figure out why (or even when) it stops listening on port 953. Does anyone have any suggestions? -- Do things because you should, not just because you can. John Thurston907-465-8591 john.thurs...@alaska.gov Department of Administration State of Alaska On 12/11/2020 11:13 AM, John Thurston wrote: Running BIND 9.16.9 on CentOS 8 I have the following in my .conf controls { inet 127.0.0.1 port 953 allow { 127.0.0.1; } keys { "mykey"; }; inet 10.2.0.1 port 953 allow { 10.2.3.3; 10.2.4.3; } keys { "threekey"; "fourkey"; }; }; And I normally can see the named process is listening on tcp:953 on both 127.0.0.1 and 10.2.0.1. But sometimes later, I find it listening only on 127.0.0.1. If I do an 'rndc reconfig', it starts listening again on both addresses. Normal DNS service has continued uninterrupted. I can't find footprints left from anything falling down. I'd could just install a watchdog to 'reconfig' whenever port 953 stops answering, but I'd rather figure out why it is stopping and correct the problem. To do that, I need more information. Am I not looking in the correct log? Do I need to crank up the logging level for something? If so, for what? and how high? ___ Please visit https://lists.isc.org/mailman/listinfo/bind-users to unsubscribe from this list ISC funds the development of this software with paid support subscriptions. Contact us at https://www.isc.org/contact/ for more information. bind-users mailing list bind-users@lists.isc.org https://lists.isc.org/mailman/listinfo/bind-users
Re: forwarding zone setup from a BIND slave (without recursion?)
Chuck Aurora wrote: > > A stub or static-stub zone would not require recursion. In that case > named is asking for authoritative data from upstream. But type > forward zones indeed cannot work if recursion is disabled. Be careful in this kind of situation to be very clear about which client or server is doing what: in this case, it isn't clear what doesn't require recursion for stub or static stub. All three types of zone configuration (stub, static stub, and forward) are only useful on a server that is providing recursive service. Forward zones require the upstream server to be recursive too. Stub and static-stub expect the upstream server to be authoritative; the stub server list is a hint that gets replaced by the authoritative server list from the zone (a bit like the root hints) whereas static-stub only uses the configured upstream servers. > > What I've learned from this list is that you should split > > authoritative and recursive service. > > I would suggest that as a general best practice, but not an absolute > one. There's nothing wrong with having internal-only authoritative > zones on your recursive resolver. The potential problem comes when > you're a globally-published NS for your zones; having recursion > enabled can make you vulnerable to more possible attacks. Right: the rule is that authoritative servers listed as targets of NS records should be authoritative-only; it's OK if recursive servers have authoritative copies of zones: it can make them more resilient to outages, though it does slightly weird things to DNSSEC validation. Tony. -- f.anthony.n.finchhttps://dotat.at/ Whitby to Gibraltar Point: Northwest 4 to 6 becoming variable 2 to 4, then southwest 4 to 6 later. Very rough at first in north, otherwise moderate or rough. Snow showers, then rain for a time later. Good, occasionally very poor at first. ___ Please visit https://lists.isc.org/mailman/listinfo/bind-users to unsubscribe from this list ISC funds the development of this software with paid support subscriptions. Contact us at https://www.isc.org/contact/ for more information. bind-users mailing list bind-users@lists.isc.org https://lists.isc.org/mailman/listinfo/bind-users
Re: forwarding zone setup from a BIND slave (without recursion?)
On 2021-04-07 03:59, Marki wrote: To elaborate a little bit on that... Indeed that is how it works, unfortunately. When you start using forwarders or stubs, recursion needs to be enabled because you're no longer looking for your own authoritative data only. A stub or static-stub zone would not require recursion. In that case named is asking for authoritative data from upstream. But type forward zones indeed cannot work if recursion is disabled. What I've learned from this list is that you should split authoritative and recursive service. I would suggest that as a general best practice, but not an absolute one. There's nothing wrong with having internal-only authoritative zones on your recursive resolver. The potential problem comes when you're a globally-published NS for your zones; having recursion enabled can make you vulnerable to more possible attacks. I'd say it depends more who/what you are. Small-timers are not at so much risk for this than large sites and ISPs. But there too, the paranoid would go for two instances of named, authoritative and recursive, on a small hosted server even where it's only offering recursion to itself. May I ask what is the reasoning behind your current setup (pointing your users to the non-recursive service)? What would you like to achieve? What would you like to prevent? Agreed, that is strange. It does not seem that an authoritative-only named can be very useful for end users. ___ Please visit https://lists.isc.org/mailman/listinfo/bind-users to unsubscribe from this list ISC funds the development of this software with paid support subscriptions. Contact us at https://www.isc.org/contact/ for more information. bind-users mailing list bind-users@lists.isc.org https://lists.isc.org/mailman/listinfo/bind-users
Re: forwarding zone setup from a BIND slave (without recursion?)
Hello, On 4/7/2021 10:35 AM, Matus UHLAR - fantomas wrote: On 06.04.21 22:47, RK K wrote: In this scenario, in-order for the secondary server to forward the DNS query to an external DNS server, is it required to enable the recursion in the global options on the secondary servers? yes. To elaborate a little bit on that... Indeed that is how it works, unfortunately. When you start using forwarders or stubs, recursion needs to be enabled because you're no longer looking for your own authoritative data only. What I've learned from this list is that you should split authoritative and recursive service. In other words, you need two types of servers: 1) A non-recursive one in the backend containing your authoritative zones only. This can be a hidden master setup, somewhat like what you are using now. 2) The one your users access has recursion enabled, and contains stubs to the authoritative service. Obviously, it can also contain stubs (or forwarders) to anywhere else. At the same time it is performing full recursive service unless you take authority for the root zone. May I ask what is the reasoning behind your current setup (pointing your users to the non-recursive service)? What would you like to achieve? What would you like to prevent? Bye, Marki ___ Please visit https://lists.isc.org/mailman/listinfo/bind-users to unsubscribe from this list ISC funds the development of this software with paid support subscriptions. Contact us at https://www.isc.org/contact/ for more information. bind-users mailing list bind-users@lists.isc.org https://lists.isc.org/mailman/listinfo/bind-users
Re: forwarding zone setup from a BIND slave (without recursion?)
On 06.04.21 22:47, RK K wrote: We have a set of BIND primary servers (MASTERs) and a set of secondary servers (slaves to the MASTERs). The secondary BIND DNS servers disabled recursion ( with "*recursion no;" *) in the global options. All the applications/systems do use secondary DNS servers for name resolution. Now there is a need to configure a forwarding zone in the "secondary DNS servers" to an external DNS server. In this scenario, in-order for the secondary server to forward the DNS query to an external DNS server, is it required to enable the recursion in the global options on the secondary servers? yes. Based on reference material, I did not see such a requirement. But my observation is the query is not getting forwarded ( tried to check using the packet trace) When recursion is enabled, the query is getting forwarded. The BIND version I am using is 9.11.2.x. -- Matus UHLAR - fantomas, uh...@fantomas.sk ; http://www.fantomas.sk/ Warning: I wish NOT to receive e-mail advertising to this address. Varovanie: na tuto adresu chcem NEDOSTAVAT akukolvek reklamnu postu. It's now safe to throw off your computer. ___ Please visit https://lists.isc.org/mailman/listinfo/bind-users to unsubscribe from this list ISC funds the development of this software with paid support subscriptions. Contact us at https://www.isc.org/contact/ for more information. bind-users mailing list bind-users@lists.isc.org https://lists.isc.org/mailman/listinfo/bind-users