AWI interface hangs, greys out, requiring refresh and re-login

Products

• CA Automic Workload Automation - Automation Engine

Issue/Introduction

AWI interface hangs randomly, grays out, which requires refreshing the page and re-login.

The webserver logfile will then show "found expired UI"

After enabling debugging on tomcat and AWI, the following messages are present in AWI logs:

2021-03-30 13:50:08,913 ionID=0000000007515544 [TRACE] NOSESSION/- NOUI [.aetracing.AutomationEngineTraceListener] - <uc-env session="">

<kick client="5000" idnr="0000000000" system="AUTOPRD">EH </kick>

</uc-env>

2021-03-30 13:50:08,913 ionID=0000000007515544 [TRACE] NOSESSION/- NOUI [.aetracing.AutomationEngineTraceListener] - <uc-env session="">

<kick client="5000" idnr="0000000000" system="AUTOPRD">EH </kick>

</uc-env>

2021-03-30 13:50:08,913 ionID=0000000007515544 [TRACE] NOSESSION/- NOUI [.aetracing.AutomationEngineTraceListener] - <uc-env session="">

<kick client="5000" idnr="0000000000" system="AUTOPRD">EH </kick>

</uc-env>

2021-03-30 13:50:08,913 ionID=0000000007515544 [TRACE] NOSESSION/- NOUI [.aetracing.AutomationEngineTraceListener] - <uc-env session="">

<kick client="5000" idnr="0000000000" system="AUTOPRD">EH </kick>

</uc-env>

2021-03-30 13:50:08,913 ionID=0000000007515544 [TRACE] NOSESSION/- NOUI [.aetracing.AutomationEngineTraceListener] - <uc-env session="">

<kick client="5000" idnr="0000000000" system="AUTOPRD">EH </kick>

</uc-env>

etc….

2021-05-05 13:02:40,473 http-nio-8080-exec-6 [TRACE] NOSESSION/- 0 [uc4.webui.common.properties.Configurable] - Loaded configuration value: heartbeatInterval -> null (20 default)

The site will continue to be greyed out until refresh.

Environment

Release : 12.3,X

Component : Automic Web Interface

Cause

Configuration

Resolution

The AWI sends heartbeat-requests to the webserver every 20 seconds. If the server does not answer within one minute, the connection is interrupted and the user needs to log in again. The same happens on the server if the client doesn't send a heartbeat for one minute.

Cause for this might be:

The browser or computer is overloaded/hanging, for reasons that might or might not have to do with the AWI. It could be caused by a different website or program on the users machine. It doesn't look like a network problem because the request is already being sent too late by the browser.
Chrome imposes some restrictions on background-tabs https://developers.google.com/web/updates/2017/03/background_tabs If the tab is put into the background and AWI uses more than 1% cpu (which is possible on slower machines), especially when viewing larger datasets, this might be a cause for throttling. 

Workaround:

Use less browser tabs/programs simultaneously, to limit CPU usage

Remediation:

In the AWI "configuration.properties", set "heartbeatInterval = 120"  or higher
this will send 3 heartbeats every 2 minutes , giving the client machines more time to respond.
Webservers need to be restarted for this to have effect so that site is not grayed out.