<div dir="ltr"><div dir="ltr"><br></div><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Mon, Jan 20, 2020 at 8:28 AM Brian J. Murrell <<a href="mailto:brian@interlinx.bc.ca">brian@interlinx.bc.ca</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">I'm really not sure about what the name of this feature I am going to<br>
describe would be. I would probably call it an "overlay view". But I<br>
am sure there are better names.<br>
<br>
Imagine I have a BIND 9 server for the following network topology:<br>
<br>
<br>
Network 1<br>
<a href="http://192.168.1.0/24" rel="noreferrer" target="_blank">192.168.1.0/24</a> ------------------------<br>
-------------------------|.254 |<br>
| Router |<br>
Network 2 | |<br>
<a href="http://192.168.2.0/24" rel="noreferrer" target="_blank">192.168.2.0/24</a> | |<br>
-------------------------|.254 |<br>
| |<br>
Network 3 | |<br>
<a href="http://192.168.3.0/24" rel="noreferrer" target="_blank">192.168.3.0/24</a> | |<br>
-------------------------|.254 |<br>
------------------------<br>
<br>
There are a few dozen hosts/services on Network 3 which hosts from<br>
Network 1 and Network 2 need to resolve names of. All pretty<br>
straightforward.<br>
<br>
But the hosts on Network 1 and Network 2 need to resolve the same name<br>
(let's call it "gateway") to the address of their interface on Router. <br>
So that is, hosts on Network 1 want a query of "gateway." to resolve to<br>
192.168.1.254 and hosts on Network 2 want a query of "gateway." to<br>
resolve to 192.168.2.254.<br>
<br>
So this is currently all achievable through "views" in BIND 9, but<br>
requires that the zone data for each view be 98% duplicate (Network 3<br>
resources) and continually copy-n-paste updated whenever names on<br>
Network 3 are added.<br>
<br>
What I am looking for is a way to save the duplicate copying of Network<br>
3 resources to the views for Network 1 and Network 2. This is where<br>
the term "overlay" comes in. What I'd like to do is reference a single<br>
copy of data from Network 3 in Network 1 and 2's views but "overlay"<br>
some view-specific resources on top of that, namely the "gateway."<br>
name, with it's per-view specific value.<br>
<br>
Thoughts?<br>
<br>
b.<br><br></blockquote><div><br></div><div>What I have set up, is for the few names that need to be different, use CNAME to a zone that is different in each view:</div><div><br></div><div>This zone is same in all views:</div><div>zone <a href="http://example.com">example.com</a></div><div><a href="http://host1.example.com">host1.example.com</a> IN A 10.0.0.4</div><div><a href="http://host2.example.com">host2.example.com</a> IN A 10.1.1.7</div><div><a href="http://router.example.com">router.example.com</a> CNAME <a href="http://router.splitview.example.com">router.splitview.example.com</a></div><div><br></div><div>Then in one view:</div><div>zone <a href="http://splitview.example.com">splitview.example.com</a></div><div><a href="http://router.splitview.example.com">router.splitview.example.com</a> IN A 10.0.0.1</div><div><br></div><div>And the other view:</div><div>zone <a href="http://splitview.example.com">splitview.example.com</a></div><div><a href="http://router.splitview.example.com">router.splitview.example.com</a> IN A 10.1.1.1</div><div><br></div><div>Any downsides that I have not thought about?</div><div><br></div><div>-- </div><div>Bob Harold</div><div><br></div></div></div>