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52b49f4838
Implement health.Healther in erratic and kubernetes plugin. The kubernetes' healtcheck is only performed on startup - i.e. turn healthy after the initial loading. Erratic follow the drop count: every query%drop turns the healthcheck unhealthy. Fixes: #985
81 lines
1.5 KiB
Markdown
81 lines
1.5 KiB
Markdown
# erratic
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*erratic* is a plugin useful for testing client behavior.
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It returns a static response to all queries, but the responses can be delayed, dropped or truncated.
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The *erratic* plugin will respond to every A or AAAA query. For any other type it will return
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a SERVFAIL response. The reply for A will return 192.0.2.53 (see RFC 5737), for AAAA it returns
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2001:DB8::53 (see RFC 3849).
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*erratic* can also be used in conjunction with the *autopath* plugin. This is mostly to aid in
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testing.
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## Syntax
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~~~ txt
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erratic {
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drop [AMOUNT]
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truncate [AMOUNT]
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delay [AMOUNT [DURATION]]
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}
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~~~
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* `drop`: drop 1 per **AMOUNT** of queries, the default is 2.
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* `truncate`: truncate 1 per **AMOUNT** of queries, the default is 2.
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* `delay`: delay 1 per **AMOUNT** of queries for **DURATION**, the default for **AMOUNT** is 2 and
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the default for **DURATION** is 100ms.
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## Health
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This plugin implements dynamic health checking. For every dropped query it turns unhealthy.
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## Examples
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~~~ corefile
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. {
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erratic {
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drop 3
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}
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}
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~~~
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Or even shorter if the defaults suits you. Note this only drops queries, it does not delay them.
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~~~ corefile
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. {
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erratic
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}
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~~~
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Delay 1 in 3 queries for 50ms
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~~~ corefile
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. {
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erratic {
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delay 3 50ms
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}
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}
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~~~
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Delay 1 in 3 and truncate 1 in 5.
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~~~ corefile
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. {
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erratic {
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delay 3 5ms
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truncate 5
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}
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}
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~~~
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Drop every second query.
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~~~ corefile
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. {
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erratic {
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drop 2
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truncate 2
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}
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}
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~~~
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