Document current limitations of loop (#1996)

* Document current limitations of loop

* Update README.md
This commit is contained in:
Chris O'Haver
2018-07-23 15:37:41 -04:00
committed by Miek Gieben
parent b7ae8d4e86
commit 992e7928c7

View File

@@ -2,7 +2,7 @@
## Name ## Name
*loop* - detect forwarding loops and halt the server. *loop* - detect simple forwarding loops and halt the server.
## Description ## Description
@@ -13,7 +13,7 @@ The plugin will try to send the query for up to 30 seconds. This is done to give
to start up. Once a query has been successfully sent *loop* disables itself to prevent a query of to start up. Once a query has been successfully sent *loop* disables itself to prevent a query of
death. death.
The query send is `<random number>.<random number>.zone` with type set to HINFO. The query sent is `<random number>.<random number>.zone` with type set to HINFO.
## Syntax ## Syntax
@@ -38,3 +38,10 @@ After CoreDNS has started it stops the process while logging:
~~~ txt ~~~ txt
plugin/loop: Seen "HINFO IN 5577006791947779410.8674665223082153551." more than twice, loop detected plugin/loop: Seen "HINFO IN 5577006791947779410.8674665223082153551." more than twice, loop detected
~~~ ~~~
## Limitations
This plugin only attempts to find simple static forwarding loops at start up time. To detect a loop, all of the following must be true
* the loop must be present at start up time.
* the loop must occur for at least the `HINFO` query type.