Wednesday, June 24, 2020 No buffer space available (maximum connections reached?)

I have come across an issue that Tableau server degraded suddenly. We had to restart the services to bring Tableau server online.

We see below errors from the log file and after research, we found that Tableau Server Port Exhaustion caused the issue

Errors in Server event log
TCP/IP failed to establish an outgoing connection because the selected local endpoint was recently used to connect to the same remote endpoint. This error typically occurs when outgoing connections are opened and closed at a high rate, causing all available local ports to be used and forcing TCP/IP to reuse a local port for an outgoing connection. To minimize the risk of data corruption, the TCP/IP standard requires a minimum time period to elapse between successive connections from a given local endpoint to a given remote endpoint.

Error in Tableau log files
2020-07-05 07:10:42.800 -0700 (,,,) StatusServerThread_dataserver_2 : INFO com.tableausoftware.service.thrift.win32.NamedPipeServerTransport - Awaiting client connection on \\.\pipe\dataserver_2-status, handle native@0x1a3c.
2020-07-05 07:10:49.990 -0700 (,,,) FilestoreHostLocatorThread : ERROR org.apache.curator.framework.imps.CuratorFrameworkImpl - Background exception was not retry-able or retry gave up Couldn't instantiate org.apache.zookeeper.ClientCnxnSocketNIO
at org.apache.zookeeper.ZooKeeper.getClientCnxnSocket(
at org.apache.zookeeper.ZooKeeper.<init>(
at org.apache.curator.utils.DefaultZookeeperFactory.newZooKeeper(
at org.apache.curator.framework.imps.CuratorFrameworkImpl$2.newZooKeeper(
at org.apache.curator.HandleHolder$1.getZooKeeper(
at org.apache.curator.HandleHolder.getZooKeeper(
at org.apache.curator.ConnectionState.reset(
at org.apache.curator.ConnectionState.start(
at org.apache.curator.CuratorZookeeperClient.start(
at org.apache.curator.framework.imps.CuratorFrameworkImpl.start(
at com.tableausoftware.tdfs.common.ZkConnection.<init>(
at com.tableausoftware.tdfs.common.ZkConnectionProvider.getConnection(
at com.tableausoftware.tdfs.common.HostLocator.lambda$initialize$1(
at java.util.concurrent.Executors$
at java.util.concurrent.FutureTask.runAndReset(
at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.access$301(
at java.util.concurrent.ScheduledThreadPoolExecutor$
at java.util.concurrent.ThreadPoolExecutor.runWorker(
at java.util.concurrent.ThreadPoolExecutor$
Caused by: java.lang.reflect.InvocationTargetException
at sun.reflect.GeneratedConstructorAccessor105.newInstance(Unknown Source)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(
at java.lang.reflect.Constructor.newInstance(
at org.apache.zookeeper.ZooKeeper.getClientCnxnSocket(
... 19 more
Caused by: Unable to establish loopback connection at$
at Method)
at org.apache.zookeeper.ClientCnxnSocketNIO.<init>(
... 23 more

Caused by: No buffer space available (maximum connections reached?): bind
1. To Identify the dynamic port range

Open a command prompt as an administrator, and run the following command to determine the dynamic port range:

netsh int ipv4 show dynamicportrange tcp
netsh int ipv6 show dynamicportrange tcp

The command will display the port number of the first dynamic port, and the number of ports. You need to add the number of ports to the start port to determine the port range.

2. Run below command to view ports currently in use
netstat –n 

3. Run the following command to increase the dynamic port range:

netsh int <ipv4|ipv6> set dynamicportrange <tcp|udp> start=number num=range store=<active/persistent>

Note that port 65535 is the maximum port number . You can start by setting the range to include ports 32767 through 65535

Also refer below article To determine port exhaustion caused the issue.,is%20the%20maximum%20port%20number.

Refer below article identify port-exhaustion at server side. 

Thanks & Regards,
Satishbabu Gunukula, Oracle ACE


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