From d9a7e666770b3729befd802977510197237af712 Mon Sep 17 00:00:00 2001 From: yubiuser Date: Mon, 21 Dec 2020 13:38:51 +0100 Subject: [PATCH 1/6] Add hint to the web interface about the limits of CNMAE records Signed-off-by: yubiuser --- cname_records.php | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/cname_records.php b/cname_records.php index d428ac15..e987412a 100644 --- a/cname_records.php +++ b/cname_records.php @@ -39,6 +39,10 @@
+ Hints: +

The target of a CNAME must be a domain that the Pi-hole knows the A value for, or is authoritative for that domain.

+

Pi-hole will not do additional queries if you set the target to a domain that isn't already known. It will return the information it knows at the time of the query, + without having to send additional queries to an upstream for resolution.

From f536eab77e7c7c013c6b1524b96915fc7ed0f582 Mon Sep 17 00:00:00 2001 From: yubiuser Date: Mon, 21 Dec 2020 17:41:04 +0100 Subject: [PATCH 2/6] Further enhance explanation Signed-off-by: yubiuser --- cname_records.php | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/cname_records.php b/cname_records.php index e987412a..b704ebb1 100644 --- a/cname_records.php +++ b/cname_records.php @@ -39,10 +39,10 @@
- Hints: + Note:

The target of a CNAME must be a domain that the Pi-hole knows the A value for, or is authoritative for that domain.

Pi-hole will not do additional queries if you set the target to a domain that isn't already known. It will return the information it knows at the time of the query, - without having to send additional queries to an upstream for resolution.

+ without having to send additional queries to an upstream for resolution. That means, for example, target domains that exist as DHCP leases only will not be fully resolved until you specify an explicit DNS entry.

From 598a7766f26e01a60dae4094c51da9e9c97caa24 Mon Sep 17 00:00:00 2001 From: yubiuser Date: Mon, 21 Dec 2020 18:16:28 +0100 Subject: [PATCH 3/6] Add code formating Signed-off-by: yubiuser --- cname_records.php | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/cname_records.php b/cname_records.php index b704ebb1..4cee877a 100644 --- a/cname_records.php +++ b/cname_records.php @@ -40,7 +40,7 @@
Note: -

The target of a CNAME must be a domain that the Pi-hole knows the A value for, or is authoritative for that domain.

+

The target of a CNAME must be a domain that the Pi-hole knows the A value for, or is authoritative for that domain.

Pi-hole will not do additional queries if you set the target to a domain that isn't already known. It will return the information it knows at the time of the query, without having to send additional queries to an upstream for resolution. That means, for example, target domains that exist as DHCP leases only will not be fully resolved until you specify an explicit DNS entry.

From 890827b2221b81ff5132e0e37557b518bb105770 Mon Sep 17 00:00:00 2001 From: yubiuser Date: Thu, 24 Dec 2020 08:46:39 +0100 Subject: [PATCH 4/6] Add note on CNAME external domains Signed-off-by: yubiuser --- cname_records.php | 1 + 1 file changed, 1 insertion(+) diff --git a/cname_records.php b/cname_records.php index 4cee877a..1b48b10b 100644 --- a/cname_records.php +++ b/cname_records.php @@ -43,6 +43,7 @@

The target of a CNAME must be a domain that the Pi-hole knows the A value for, or is authoritative for that domain.

Pi-hole will not do additional queries if you set the target to a domain that isn't already known. It will return the information it knows at the time of the query, without having to send additional queries to an upstream for resolution. That means, for example, target domains that exist as DHCP leases only will not be fully resolved until you specify an explicit DNS entry.

+

Additionally, you can't CNAME external domains (bing.com to google.com) successfully as this would result in an invalid SSL certificate error.

From c23e6d7cc2d63af9c53f4f7f60b0d59cb91f9e71 Mon Sep 17 00:00:00 2001 From: yubiuser Date: Thu, 24 Dec 2020 09:25:49 +0100 Subject: [PATCH 5/6] Revise DHCP text Signed-off-by: yubiuser --- cname_records.php | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/cname_records.php b/cname_records.php index 1b48b10b..ff7c7d9b 100644 --- a/cname_records.php +++ b/cname_records.php @@ -41,8 +41,8 @@
Note:

The target of a CNAME must be a domain that the Pi-hole knows the A value for, or is authoritative for that domain.

-

Pi-hole will not do additional queries if you set the target to a domain that isn't already known. It will return the information it knows at the time of the query, - without having to send additional queries to an upstream for resolution. That means, for example, target domains that exist as DHCP leases only will not be fully resolved until you specify an explicit DNS entry.

+

Pi-hole will not do additional queries if you set the target to a domain that isn't already known. It just returns the information it knows at the time of the query. + This results in certain limitations for CNAME targets, for instance, only active leases work as targets.

Additionally, you can't CNAME external domains (bing.com to google.com) successfully as this would result in an invalid SSL certificate error.

From 561083b250f03460b0c91497e35371d6f3b98842 Mon Sep 17 00:00:00 2001 From: yubiuser Date: Thu, 24 Dec 2020 10:23:56 +0100 Subject: [PATCH 6/6] Improve explanation Signed-off-by: yubiuser --- cname_records.php | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/cname_records.php b/cname_records.php index ff7c7d9b..0e4e7e16 100644 --- a/cname_records.php +++ b/cname_records.php @@ -40,10 +40,10 @@
Note: -

The target of a CNAME must be a domain that the Pi-hole knows the A value for, or is authoritative for that domain.

-

Pi-hole will not do additional queries if you set the target to a domain that isn't already known. It just returns the information it knows at the time of the query. - This results in certain limitations for CNAME targets, for instance, only active leases work as targets.

-

Additionally, you can't CNAME external domains (bing.com to google.com) successfully as this would result in an invalid SSL certificate error. +

The target of a CNAME must be a domain that the Pi-hole already has in its cache or is authoritative for. This is an universal limitation of CNAME records.

+

The reason for this is that Pi-hole will not send additional queries upstream when serving CNAME replies. As consequence, if you set a target that isn't already known, the reply to the client may be incomplete. Pi-hole just returns the information it knows at the time of the query. This results in certain limitations for CNAME targets, + for instance, only active DHCP leases work as targets - mere DHCP leases aren't sufficient as they aren't (yet) valid DNS records.

+

Additionally, you can't CNAME external domains (bing.com to google.com) successfully as this could result in invalid SSL certificate errors when the target server does not serve content for the requested domain.