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Copyright (C) The Arvados Authors. All rights reserved.

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h3(#MaxGatewayTunnels). API.MaxGatewayTunnels

Each Arvados container that runs on your HPC cluster will bring up a long-lived connection to the Arvados controller and keep it open for the entire duration of the container. This connection is used to access real-time container logs from Workbench, and to enable the "container shell":{{site.baseurl}}/install/container-shell-access.html feature.

Set the @MaxGatewayTunnels@ config entry high enough to accommodate the maximum number of containers you expect to run concurrently on your HPC cluster, plus incoming container shell sessions.

<notextile>
<pre>    API:
      MaxGatewayTunnels: 2000</pre>
</notextile>

Also, configure Nginx (and any other HTTP proxies or load balancers running between the HPC and Arvados controller) to allow the expected number of connections, i.e., @MaxConcurrentRequests + MaxQueuedRequests + MaxGatewayTunnels@.