Bug ID 1042509: On an HTTP2 gateway virtual server, TMM does not ever update the stream's window for a large POST request

Last Modified: May 29, 2024

Affected Product(s):
BIG-IP LTM(all modules)

Known Affected Versions:
16.1.0, 16.1.1, 16.1.2, 16.1.2.1

Fixed In:
17.0.0, 16.1.2.2

Opened: Aug 24, 2021

Severity: 3-Major

Symptoms

On an HTTP2 gateway virtual server (HTTP/2 on clientside, no httprouter profile), TMM does not update the stream's window (i.e. acking data at the HTTP/2 stream layer). This causes large HTTP requests with payloads (i.e. POSTs) to stall and eventually time out. TMM does sometimes send WINDOW_UPDATE messages for the entire connection, but not for the stream. Since flow control is required at both the connection and stream levels, the client stalls out.

Impact

Client data transfer through HTTP/2 virtual server (POST / PUT / etc) fails.

Conditions

-- Virtual server with HTTP2 profile -- Configured as HTTP2 Gateway (HTTP2 profile on clientside and no 'httprouter' profile) -- Client sends large data transfer to the virtual server

Workaround

Use an HTTP router profile (assign the 'httprouter' profile to the virtual server, or select the 'HTTP MRF Router' option in TMUI)

Fix Information

None

Behavior Change

Guides & references

K10134038: F5 Bug Tracker Filter Names and Tips