# system.tag.queryTagHistory: Read timed out - Communications link failure

**URL:** <https://forum.inductiveautomation.com/t/system-tag-querytaghistory-read-timed-out-communications-link-failure/21563>\
**Category:** Ignition\
**Tags:** ignition79, scripting\
**Created:** [December 21, 2018, 7:33am UTC](https://forum.inductiveautomation.com/t/system-tag-querytaghistory-read-timed-out-communications-link-failure/21563 "2018-12-21T07:33:57Z")\
**Posts on this page:** 4\
**Page:** 1

<div class="post-metadata">

**Author:** ![tyler.bennett](https://avatars.discourse-cdn.com/v4/letter/t/f04885/32.png) [@tyler.bennett](https://forum.inductiveautomation.com/u/tyler.bennett)\
**Post date:** [December 21, 2018, 7:33am UTC](https://forum.inductiveautomation.com/t/system-tag-querytaghistory-read-timed-out-communications-link-failure/21563/1 "2018-12-21T07:33:57Z")

</div>

I’ve been working on a window to allow a user to do custom query and export of historical data (there did not seem to be any existing component for this, let me know if I missed it). Basically I have added components and scripting which allow selection of tags and determination of the other parameters required to execute a scripted query with system.tag.queryTagHistory. Some of the queries can run long and I found that the query was timing out with error **“Read timed out”** … No problem, increased the **timeout** parameter that I fed to system.tag.queryTagHistory (greater than the 60000 ms default). However now I find that I get a different error, exactly at the two minute mark indicating Communications Link Failure

**com.inductiveautomation.ignition.client.gateway\_interface.GatewayException: Communications link failure**

**The last packet successfully received from the server was 120,001 milliseconds ago. The last packet sent successfully to the server was 120,000 milliseconds ago.**

Given the this happens right at two minutes I figure that this is due to some other configured timeout but I have not been able to to figure out how to extend this. I can get the query to complete in less than two minutes by selecting a much smaller time period but I need the query to cover a larger time period to satisfy my objectives.

Has anyone run into this problem and found a resolution?

**Error screenshot:**

 ![](https://us1.discourse-cdn.com/inductiveautomation/original/2X/a/a7325fcd83c884cff7a5c0a86ecdb67c1bc0d108.png)

**Error Details:**

```auto
Traceback (most recent call last):
  File "<event:actionPerformed>", line 132, in <module>

The last packet successfully received from the server was 120,001 milliseconds ago. The last packet sent successfully to the server was 120,000 milliseconds ago.

	at com.inductiveautomation.ignition.client.gateway_interface.GatewayInterface.newGatewayException(GatewayInterface.java:341)

	at com.inductiveautomation.ignition.client.gateway_interface.GatewayInterface.sendMessage(GatewayInterface.java:315)

	at com.inductiveautomation.ignition.client.gateway_interface.GatewayInterface.runTagHistoryQuery(GatewayInterface.java:726)

	at com.inductiveautomation.ignition.client.script.ClientTagUtilities.queryTagHistoryImpl(ClientTagUtilities.java:328)

	at com.inductiveautomation.ignition.common.script.builtin.AbstractTagUtilities.queryTagHistory(AbstractTagUtilities.java:537)

	at sun.reflect.GeneratedMethodAccessor478.invoke(Unknown Source)

	at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)

	at java.lang.reflect.Method.invoke(Unknown Source)

com.inductiveautomation.ignition.client.gateway_interface.GatewayException: com.inductiveautomation.ignition.client.gateway_interface.GatewayException: Communications link failure

The last packet successfully received from the server was 120,001 milliseconds ago. The last packet sent successfully to the server was 120,000 milliseconds ago.

	at org.python.core.Py.JavaError(Py.java:495)
	at org.python.core.Py.JavaError(Py.java:488)
	at org.python.core.PyReflectedFunction. __call__ (PyReflectedFunction.java:188)
	at com.inductiveautomation.ignition.common.script.ScriptManager$ReflectedInstanceFunction. __call__ (ScriptManager.java:431)
	at org.python.core.PyObject. __call__ (PyObject.java:320)
	at org.python.pycode._pyx883.f$0(<event:actionPerformed>:159)
	at org.python.pycode._pyx883.call_function(<event:actionPerformed>)
	at org.python.core.PyTableCode.call(PyTableCode.java:165)
	at org.python.core.PyCode.call(PyCode.java:18)
	at org.python.core.Py.runCode(Py.java:1275)
	at com.inductiveautomation.ignition.common.script.ScriptManager.runCode(ScriptManager.java:636)
	at com.inductiveautomation.factorypmi.application.binding.action.ActionAdapter.runActions(ActionAdapter.java:180)
	at com.inductiveautomation.factorypmi.application.binding.action.ActionAdapter.invoke(ActionAdapter.java:271)
	at com.inductiveautomation.factorypmi.application.binding.action.RelayInvocationHandler.invoke(RelayInvocationHandler.java:57)
	at com.sun.proxy.$Proxy18.actionPerformed(Unknown Source)
	at javax.swing.AbstractButton.fireActionPerformed(Unknown Source)
	at javax.swing.AbstractButton$Handler.actionPerformed(Unknown Source)
	at javax.swing.DefaultButtonModel.fireActionPerformed(Unknown Source)
	at javax.swing.DefaultButtonModel.setPressed(Unknown Source)
	at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(Unknown Source)
	at java.awt.Component.processMouseEvent(Unknown Source)
	at javax.swing.JComponent.processMouseEvent(Unknown Source)
	at java.awt.Component.processEvent(Unknown Source)
	at java.awt.Container.processEvent(Unknown Source)
	at java.awt.Component.dispatchEventImpl(Unknown Source)
	at java.awt.Container.dispatchEventImpl(Unknown Source)
	at java.awt.Component.dispatchEvent(Unknown Source)
	at java.awt.LightweightDispatcher.retargetMouseEvent(Unknown Source)
	at java.awt.LightweightDispatcher.processMouseEvent(Unknown Source)
	at java.awt.LightweightDispatcher.dispatchEvent(Unknown Source)
	at java.awt.Container.dispatchEventImpl(Unknown Source)
	at java.awt.Window.dispatchEventImpl(Unknown Source)
	at java.awt.Component.dispatchEvent(Unknown Source)
	at java.awt.EventQueue.dispatchEventImpl(Unknown Source)
	at java.awt.EventQueue.access$500(Unknown Source)
	at java.awt.EventQueue$3.run(Unknown Source)
	at java.awt.EventQueue$3.run(Unknown Source)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(Unknown Source)
	at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(Unknown Source)
	at java.awt.EventQueue$4.run(Unknown Source)
	at java.awt.EventQueue$4.run(Unknown Source)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(Unknown Source)
	at java.awt.EventQueue.dispatchEvent(Unknown Source)
	at java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source)
	at java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source)
	at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)
	at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
	at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
	at java.awt.EventDispatchThread.run(Unknown Source)
Caused by: com.inductiveautomation.ignition.client.gateway_interface.GatewayException: Communications link failure

The last packet successfully received from the server was 120,001 milliseconds ago. The last packet sent successfully to the server was 120,000 milliseconds ago.
	at com.inductiveautomation.ignition.client.gateway_interface.GatewayInterface.newGatewayException(GatewayInterface.java:341)
	at com.inductiveautomation.ignition.client.gateway_interface.GatewayInterface.sendMessage(GatewayInterface.java:315)
	at com.inductiveautomation.ignition.client.gateway_interface.GatewayInterface.runTagHistoryQuery(GatewayInterface.java:726)
	at com.inductiveautomation.ignition.client.script.ClientTagUtilities.queryTagHistoryImpl(ClientTagUtilities.java:328)
	at com.inductiveautomation.ignition.common.script.builtin.AbstractTagUtilities.queryTagHistory(AbstractTagUtilities.java:537)
	at sun.reflect.GeneratedMethodAccessor478.invoke(Unknown Source)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
	at java.lang.reflect.Method.invoke(Unknown Source)
	at org.python.core.PyReflectedFunction. __call__ (PyReflectedFunction.java:186)
	... 48 more
Caused by: com.mysql.jdbc.exceptions.jdbc4.CommunicationsException: Communications link failure

The last packet successfully received from the server was 120,001 milliseconds ago. The last packet sent successfully to the server was 120,000 milliseconds ago.
	at sun.reflect.GeneratedConstructorAccessor162.newInstance(null)
	at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(null)
	at java.lang.reflect.Constructor.newInstance(null)
	at com.mysql.jdbc.Util.handleNewInstance(Util.java:411)
	at com.mysql.jdbc.SQLError.createCommunicationsException(SQLError.java:1117)
	at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:3603)
	at com.mysql.jdbc.MysqlIO.reuseAndReadPacket(MysqlIO.java:3492)
	at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:4043)
	at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:2503)
	at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2664)
	at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2794)
	at com.mysql.jdbc.PreparedStatement.executeInternal(PreparedStatement.java:2155)
	at com.mysql.jdbc.PreparedStatement.executeQuery(PreparedStatement.java:2322)
	at org.apache.commons.dbcp.DelegatingPreparedStatement.executeQuery(DelegatingPreparedStatement.java:93)
	at com.inductiveautomation.ignition.gateway.datasource.SRConnectionWrapper$SRPreparedStatement.executeQuery(SRConnectionWrapper.java:948)
	at com.inductiveautomation.gateway.tags.history.query.DatasourceQueryExecutor.advancePartition(DatasourceQueryExecutor.java:1048)
	at com.inductiveautomation.gateway.tags.history.query.DatasourceQueryExecutor.primeRead(DatasourceQueryExecutor.java:969)
	at com.inductiveautomation.ignition.gateway.sqltags.history.query.AbstractHistoryLoader.startReading(AbstractHistoryLoader.java:104)
	at com.inductiveautomation.ignition.gateway.sqltags.history.query.AggregateHistoryQueryExecutor.startReading(AggregateHistoryQueryExecutor.java:85)
	at com.inductiveautomation.ignition.gateway.sqltags.history.query.HistoryWriter.readData(HistoryWriter.java:301)
	at com.inductiveautomation.ignition.gateway.sqltags.history.query.HistoryWriter.execute(HistoryWriter.java:230)
	at com.inductiveautomation.ignition.gateway.sqltags.SQLTagsManagerImpl.queryHistory(SQLTagsManagerImpl.java:1297)
	at com.inductiveautomation.ignition.gateway.project.ProjectSettingsCache$ProjectDefaultTagManagerFacade.queryHistory(ProjectSettingsCache.java:673)
	at com.inductiveautomation.ignition.gateway.servlets.gateway.functions.QueryTagHistory.invoke(QueryTagHistory.java:96)
	at com.inductiveautomation.ignition.gateway.servlets.Gateway.doPost(Gateway.java:404)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:707)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:790)
	at com.inductiveautomation.ignition.gateway.bootstrap.MapServlet.service(MapServlet.java:85)
	at org.eclipse.jetty.servlet.ServletHolder.handle(ServletHolder.java:837)
	at org.eclipse.jetty.servlet.ServletHandler.doHandle(ServletHandler.java:583)
	at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:143)
	at org.eclipse.jetty.security.SecurityHandler.handle(SecurityHandler.java:548)
	at org.eclipse.jetty.server.session.SessionHandler.doHandle(SessionHandler.java:226)
	at org.eclipse.jetty.server.handler.ContextHandler.doHandle(ContextHandler.java:1160)
	at org.eclipse.jetty.servlet.ServletHandler.doScope(ServletHandler.java:511)
	at org.eclipse.jetty.server.session.SessionHandler.doScope(SessionHandler.java:185)
	at org.eclipse.jetty.server.handler.ContextHandler.doScope(ContextHandler.java:1092)
	at org.eclipse.jetty.server.handler.ScopedHandler.handle(ScopedHandler.java:141)
	at org.eclipse.jetty.server.handler.HandlerList.handle(HandlerList.java:52)
	at org.eclipse.jetty.server.handler.HandlerWrapper.handle(HandlerWrapper.java:134)
	at org.eclipse.jetty.server.Server.handle(Server.java:518)
	at org.eclipse.jetty.server.HttpChannel.handle(HttpChannel.java:308)
	at org.eclipse.jetty.server.HttpConnection.onFillable(HttpConnection.java:244)
	at org.eclipse.jetty.io.AbstractConnection$ReadCallback.succeeded(AbstractConnection.java:273)
	at org.eclipse.jetty.io.FillInterest.fillable(FillInterest.java:95)
	at org.eclipse.jetty.io.ssl.SslConnection.onFillable(SslConnection.java:186)
	at org.eclipse.jetty.io.AbstractConnection$ReadCallback.succeeded(AbstractConnection.java:273)
	at org.eclipse.jetty.io.FillInterest.fillable(FillInterest.java:95)
	at org.eclipse.jetty.io.SelectChannelEndPoint$2.run(SelectChannelEndPoint.java:93)
	at org.eclipse.jetty.util.thread.strategy.ExecuteProduceConsume.produceAndRun(ExecuteProduceConsume.java:246)
	at org.eclipse.jetty.util.thread.strategy.ExecuteProduceConsume.run(ExecuteProduceConsume.java:156)
	at org.eclipse.jetty.util.thread.QueuedThreadPool.runJob(QueuedThreadPool.java:654)
	at org.eclipse.jetty.util.thread.QueuedThreadPool$3.run(QueuedThreadPool.java:572)
	at java.lang.Thread.run(null)

Ignition v7.9.10 (b2018112821)
Java: Oracle Corporation 1.8.0_181

```

---

<div class="post-metadata">

**Author:** ![pturmel](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/pturmel/32/3295_2.png) [@pturmel](https://forum.inductiveautomation.com/u/pturmel)\
**Post date:** [December 21, 2018, 12:35pm UTC](https://forum.inductiveautomation.com/t/system-tag-querytaghistory-read-timed-out-communications-link-failure/21563/2 "2018-12-21T12:35:05Z")

</div>

There is a project property for general client-to-gateway response timeouts. You have to increase that one, too.

---

<div class="post-metadata">

**Author:** ![tyler.bennett](https://avatars.discourse-cdn.com/v4/letter/t/f04885/32.png) [@tyler.bennett](https://forum.inductiveautomation.com/u/tyler.bennett)\
**Post date:** [December 21, 2018, 5:02pm UTC](https://forum.inductiveautomation.com/t/system-tag-querytaghistory-read-timed-out-communications-link-failure/21563/3 "2018-12-21T17:02:18Z")

</div>

@pturmel, thanks for the feedback. The project property which looks to correlate to the issue I am seeing is actually **OPC Browse Timeout**. Were you thinking of something else? I’ll do some testing with it and report back.

![](https://us1.discourse-cdn.com/inductiveautomation/original/2X/2/21987cfe35e17806e6cabd5ee5c396404c0efab2.png)

---

<div class="post-metadata">

**Author:** ![pturmel](https://sea1.discourse-cdn.com/inductiveautomation/user_avatar/forum.inductiveautomation.com/pturmel/32/3295_2.png) [@pturmel](https://forum.inductiveautomation.com/u/pturmel)\
**Post date:** [December 21, 2018, 7:33pm UTC](https://forum.inductiveautomation.com/t/system-tag-querytaghistory-read-timed-out-communications-link-failure/21563/4 "2018-12-21T19:33:54Z")

</div>

No, the “Read Timeout” right above it.