[dns-operations] Preparing resolver operators for the rollover

[Marat Khalili]

Dear Paul,
good time of the day,

Thank you for the links. Just followed instructions in first two 
sections of the first link, "Checking..." and "BIND". They were mostly 
clear and produced expected results, but I'd add add two extra 
clarifications:

* In section "Checking...", I'd reword a sentence after "dig" command 
along the following lines: "In that command, replace the string ADDRESS 
with the IPv4 or IPv6 address of each resolver server you operate, one 
at a time." Although the current wording is technically unambiguous, one 
is tempted to forget his 'resolver' comprises multiple servers.

* In section "BIND" I'd add that "directory that BIND's other files are 
created [in]" is probably specified in the "directory" statement of the 
"options" section.

(Tested stock bind versions of Ubuntu 16.04 and 14.04, correspondingly 
9.10.3-P4-Ubuntu and 9.9.5-3ubuntu0.16-Ubuntu, connected to Google DNS 
servers. Neither needed anchors update.)

--

With Best Regards,
Marat Khalili