431c70e8b9
This is a fixup for https://github.com/coredns/coredns/pull/3310 which replaced some 'iff's with 'if' under the assumption they were typos. I'm fairly confident they were "If and only if" (https://en.wikipedia.org/wiki/If_and_only_if), which is commonly shortened as "iff". I've updated them to the full length 'if, and only if' for the sake of readability. Signed-off-by: Euan Kemp <euan@ngrok.com> |
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| .. | ||
| autopath.go | ||
| autopath_test.go | ||
| cname.go | ||
| metrics.go | ||
| OWNERS | ||
| README.md | ||
| setup.go | ||
| setup_test.go | ||
autopath
Name
autopath - allows for server-side search path completion.
Description
If it sees a query that matches the first element of the configured search path, autopath will follow the chain of search path elements and return the first reply that is not NXDOMAIN. On any failures, the original reply is returned. Because autopath returns a reply for a name that wasn't the original question it will add a CNAME that points from the original name (with the search path element in it) to the name of this answer.
Syntax
autopath [ZONE...] RESOLV-CONF
- ZONES zones autopath should be authoritative for.
- RESOLV-CONF points to a
resolv.conflike file or uses a special syntax to point to another plugin. For instance@kubernetes, will call out to the kubernetes plugin (for each query) to retrieve the search list it should use.
If a plugin implements the AutoPather interface then it can be used.
Metrics
If monitoring is enabled (via the prometheus plugin) then the following metric is exported:
coredns_autopath_success_count_total{server}- counter of successfully autopath-ed queries.
The server label is explained in the metrics plugin documentation.
Examples
autopath my-resolv.conf
Use my-resolv.conf as the file to get the search path from. This file only needs to have one line:
search domain1 domain2 ...
autopath @kubernetes
Use the search path dynamically retrieved from the kubernetes plugin.
Known Issues
In Kubernetes, autopath is not compatible with pods running from Windows nodes.
If the server side search ultimately results in a negative answer (e.g. NXDOMAIN), then the client will fruitlessly search all paths manually, thus negating the autopath optimization.