VMOD_H2(3)

NAME
vmod_h2 - Module to control the built-in HTTP2 transport

SYNOPSIS

import h2 [as name] [from "path"]
BOOL is()
DURATION rapid_reset([DURATION threshold])
INT rapid_reset_limit([INT number])
DURATION rapid_reset_period([DURATION duration])
REAL rapid_reset_budget()

DESCRIPTION

This VMOD contains functions to control the HTTP2 transport built into Varnish-Cache.

  BOOL is()

Restricted to: client.

Returns true when called on a session handled by the built-in HTTP2 transport.

  DURATION rapid_reset([DURATION threshold])

Restricted to: client.

Get and optionally set the h2_rapid_reset parameter (See varnishd(1)) for this HTTP2 session only.

Returns -1 when used outside the HTTP2 transport. Otherwise returns the previous value.

If the call leads to a change in the rate limit parameters, the current budget as retuned by h2.rapid_reset_budget() is reset.

  INT rapid_reset_limit([INT number])

Restricted to: client.

Get and optionally set the h2_rapid_reset_limit parameter (See varnishd(1)) for this HTTP2 session only.

Returns -1 when used outside the HTTP2 transport. Otherwise returns the previous value.

If the call leads to a change in the rate limit parameters, the current budget as retuned by h2.rapid_reset_budget() is reset.

  DURATION rapid_reset_period([DURATION duration])

Restricted to: client.

Get and optionally set the h2_rapid_reset_period parameter (See varnishd(1)) for this HTTP2 session only.

Returns -1 when used outside the HTTP2 transport. Otherwise returns the previous value.

If the call leads to a change in the rate limit parameters, the current budget as retuned by h2.rapid_reset_budget() is reset.

  REAL rapid_reset_budget()

Restricted to: client.

Return how many RST frames classified as "rapid" the client is still allowed to send before the session is going to be closed.

SEE ALSO

•   varnishd(1)

•   vsl(7)

COPYRIGHT

Copyright 2023 UPLEX - Nils Goroll Systemoptimierung
All rights reserved.
Author: Nils Goroll <nils.goroll@uplex.de>
SPDX-License-Identifier: BSD-2-Clause
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modification, are permitted provided that the following conditions
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   notice, this list of conditions and the following disclaimer.
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