Flexbox-based dynamic layouts not supported for Android 4.4 and earlier
Valid from Pega Version 7.2.1
Flexbox-based dynamic layouts are not supported in Android 4.4 and earlier. When developing applications to be used on devices running Android 4.4 and earlier, use the inline-block layout mode for dynamic layouts.
MBean Javadocs download file
Valid from Pega Version 7.2.1
The Pega 7 Platform MBean Javadocs are no longer provided in the distribution image; however, you can download the 
MBeanJMXJavadoc.zip file that was previously provided in the distribution image.
You can also use JConsole, which is included with the Java Development Kit (JDK), to obtain MBean information. The JConsole MBean tab provides attributes, operations, notifications, and other information on all the MBeans that are registered with the MBean server.
Cannot send mobile push notifications when the Pega 7 Platform is hosted on WebSphere Application Server
Valid from Pega Version 7.2.1
Push notifications are not sent to Android or iOS mobile apps when the Pega 7 Platform is hosted on WebSphere Application Server.
Extract marker file not created at startup
Valid from Pega Version 7.2.1
The extract marker file (PegaRULES_Extract_Marker.txt) is not created at startup, because the rule utility libraries no longer need it. If you used to use the extract marker file to clear the static content file-based cache, to look up lists, or to control starting activities with web nodes, you can delete the contents of the PegaRULES temporary directory instead.
System starts slowly after upgrade or update on IBM DB2 for z/OS
Valid from Pega Version 7.2.2
Additional tables are added to upgraded and updated systems. If your system starts up very slowly after an upgrade or update, the database statistics on these new tables might not have generated correctly. To correct this issue and improve performance, your database administrator needs to manually rebuild the statistics for all tables in the rules schema.
Clustering equal to none might cause errors
Valid from Pega Version 7.2.2
Some Pega 7 Platform features might not work when theidentification/cluster/protocolsetting in the prconfig.xml file is set to none. Some features that might not work are remote tracing and management actions on the node from the Requestor Management and Agent Management landing pages. Setting the clustering protocol to none is not recommended and will not be supported in a future Pega 7 Platform release.
Excessive service invocation count
Valid from Pega Version Pega Platform
Apply a hotfix to eliminate excessive service invocations. After upgrades, the service invocation count for Lucene search results might be up to four times greater than before the upgrade. The Pega 7 Platform moved from Lucene to Elasticsearch in Pega 7.1.7.
If any of the following situations apply to your installation, you must apply a hotfix:
- You installed any version prior to Pega 7.1.7 and you do not plan to upgrade at this time.
- You upgraded from any version prior to PRPC 6.3 to any version prior to Pega 7.1.7.
- You upgraded from 7.1.6 or earlier to Pega 7.1.7 or Pega 7.1.8 and you did not change your indexing to Elasticsearch.
The workaround depends on your version:
- For PRPC 6.3 SP1, apply HFix-27840 and HFix-28856.
- For other versions of the Pega 7 Platform, use My Support Portal to request the hotfixes for your system.
Beginning with Pega 7.1.9, the issue has been resolved.
Disregard this startup error for Oracle Weblogic deployments
Valid from Pega Version 7.2.2
If you install, upgrade, or update your Oracle Weblogic application server to Pega 7.2.2, disregard the error stack that begins with text similar to the following:
ERROR - WebLogic Server 12.1.3.0.0 Wed May 21 18:53:34 PDT 2014 1604337 Oracle WebLogic Server Module Dependencies 12.1 Tue Mar 11 15:35:15 MDT 2014 WebLogic Jersey Server Integration 3.0 Fri Feb 21 10:55:11 UTC 2014 must use JDK 1.8+ with WebSocket
2016-11-07 06:13:01,690 [ WIN-L3EEURCNCP1] [ STANDARD] (pr.DefaultAsyncSupportResolver) ERROR - Real error: Unable to configure jsr356 at that stage. ServerContainer is null
This message appears because the Pega 7.2.2 real-time notification feature initially tries to use WebSocket and then falls back to long polling. The Pega 7 Platform does not support WebSocket for Oracle Weblogic servers, and instead uses long polling for real-time notifications.
Disregard this Comet support error at startup
Pega 7.2.2 introduced real-time notifications using Comet technologies like WebSocket and long polling. WebSocket provides the best results, but both WebSocket and non-blocking long polling must be supported by your application server. If your application server does not support WebSocket and non-blocking long polling, you might see an error stack that begins with text similar to the following:
ERROR - If you have more than one Connector enabled, make sure they both use the same protocol, e.g NIO/APR or HTTP for all. If not, org.atmosphere.container.BlockingIOCometSupport will be used and cannot be changed. java.lang.IllegalStateException: Tomcat failed to detect this is a Comet application because context.xml is missing or the Http11NioProtocol Connector is not enabled. You must use the atmosphere-native-runtime dependency in order to use native Comet Support
You can disregard this message.
However, to take advantage of the improvements to real-time notifications, enable WebSocket support:
- For IBM WebSphere Application Server Liberty Core, see your deployment guide for instructions on configuring the application server.
- For Red Hat JBoss, see your deployment guide for instructions on enabling WebSocket support.
- For Apache Tomcat application servers, consider upgrading to Tomcat 7.0.53 or later which supports WebSocket.
Disregard this Java script console message
Valid from Pega Version 7.2.2
Pega 7.2.2 introduced real-time notifications by using Comet technologies such as WebSocket and long polling. WebSocket provides the best results, but both WebSocket and non-blocking long polling must be supported by your application server. If your application server does not support WebSocket, you might see a JavaScript error that begins with text that is similar to the following text:
WebSocket connection to 'ws://vnbamdevapp01:8080/prweb/PRPushServlet/... Error during WebSocket handshake: Unexpected response code: 501_getWebSocket @ pzpega_ui_messaging_1802554968!!.js:1195 pzpega_ui_messaging_1802554968!!.js:3265 Websocket closed, reason: Connection was closed abnormally (that is, with no close frame being sent). - wasClean: falselog @ pzpega_ui_messaging_1802554968!!.js:3265 pzpega_ui_messaging_1802554968!!.js:3265 Websocket failed on first connection attempt. Downgrading to long-polling and resending
You can disregard this message.
However, to take advantage of the improvements to real-time notifications, enable support for WebSocket:
- For IBM WebSphere Application Server Liberty Core, see your deployment guide for instructions on configuring the application server.
- For Red Hat JBoss, see your deployment guide for instructions on enabling WebSocket support.
- For Apache Tomcat application servers, consider upgrading to Apache Tomcat 7.0.53 or later which supports WebSocket.