document fix for the example

howto/quintex.md

@@ -252,7 +252,8 @@ find its live filesystem and boot.
 If iPXE encounters a problem it will show you an error code which you
 can load in a web browser. For example, error code `3e1162` is
 available at <https://ipxe.org/err/3e1162> and is "Error: No DNS
-servers available".
+servers available". That was caused by a missing DNS server (fix: `set
+dns 1.1.1.1`).
 
 Chucking the `.iso` into the initrd is kinda icky, but the alternative
 involves using [fetch=http-url](https://manpages.debian.org/testing/live-boot-doc/live-boot.7.fr.html#fetch) which does not support DNS and