NAME¶

nbdkit-retry-request-filter - retry single requests on error

SYNOPSIS¶

 nbdkit --filter=retry-request PLUGIN
                   [retry-request-retries=N] [retry-request-delay=N]
                   [retry-request-open=false]

DESCRIPTION¶

"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.

PARAMETERS¶

retry-request-retries=N

The number of times any single request will be retried before we give up and fail the operation. The default is 2.

retry-request-delay=DELAY

The time to wait before retrying. The default is 2 seconds. Any format supported by nbdkit_parse_delay(3) is allowed here.

retry-request-open=false

If set to false, do not retry opening the plugin. The default is to treat plugin open in the same way as other requests.

FILES¶

$filterdir/nbdkit-retry-request-filter.so

The filter.

Use "nbdkit --dump-config" to find the location of $filterdir.

VERSION¶

"nbdkit-retry-filter" first appeared in nbdkit 1.30.

SEE ALSO¶

nbdkit(1), nbdkit-filter(3), nbdkit-readahead-filter(1), nbdkit-retry-filter(1), nbdkit_parse_delay(3).

AUTHORS¶

Richard W.M. Jones

COPYRIGHT¶

Copyright Red Hat

LICENSE¶

Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:

• Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
• Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.
• Neither the name of Red Hat nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission.

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