nbdkit-retry-request-filter - retry single requests on error
nbdkit --filter=retry-request PLUGIN
[retry-request-retries=N] [retry-request-delay=N]
[retry-request-open=false]nbdkit-retry-request-filter is a filter for nbdkit that transparently retries single requests if they fail. This is useful for plugins that are not completely reliable or have random behaviour. For example nbdkit-curl-plugin(1) might behave this way if pointed at a load balancer which sometimes redirects to a web server that is not responsive.
An alternative filter with different trade-offs is nbdkit-retry-filter(1). That filter is more heavyweight because it always reopens the whole plugin connection on failure.
The number of times any single request will be retried before we give up and fail the operation. The default is 2.
The time to wait before retrying. The default is 2 seconds. Any format supported by nbdkit_parse_delay(3) is allowed here.
If set to false, do not retry opening the plugin. The default is to treat plugin open in the same way as other requests.
The filter.
Use nbdkit --dump-config to find the location of $filterdir.
nbdkit-retry-filter first appeared in nbdkit 1.30.
nbdkit(1), nbdkit-filter(3), nbdkit-readahead-filter(1), nbdkit-retry-filter(1), nbdkit_parse_delay(3).
Richard W.M. Jones
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