APAR status
Closed as program error.
Error description
This APAR is to provide a configurable property to allow a user to specify a period of time in which a connection to an FTP file server must complete before giving up. This is currently available for SFTP and FTPS connections, however no such option is currently available for FTP connections. This means that, if an FTP file server is slow to complete the FTP connection process, or becomes unresponsive during the connection attempt, the thread establishing the connection can block. A Javacore of the WebSphere MQ Managed File Transfer protocol bridge agent taken at the time such a situation occurs, would show a thread and Java Stack such as that below: "FileIOWorker-0:1" J9VMThread:0x00002B5B94029D00, j9thread_t:0x00002B5B449D3CC0, java/lang/Thread:0x00002B5B501267C0, state:R, prio=5 (java/lang/Thread getId:0xE04, isDaemon:true) (native thread ID:0x2F1B, native priority:0x5, native policy:UNKNOWN) (native stack address range from:0x00002B5BC869A000, to:0x00002B5BC86DB000, size:0x41000) Java callstack: at java/net/SocketInputStream.socketRead0(Native Method) at java/net/SocketInputStream.read(SocketInputStream.java:129(Compi led Code)) at sun/nio/cs/StreamDecoder$CharsetSD.readBytes(StreamDecoder.java: 452(Compiled Code)) at sun/nio/cs/StreamDecoder$CharsetSD.implRead(StreamDecoder.java:4 94(Compiled Code)) at sun/nio/cs/StreamDecoder.read(StreamDecoder.java:222(Compiled Code)) at java/io/InputStreamReader.read(InputStreamReader.java:177(Compil ed Code)) at java/io/BufferedReader.fill(BufferedReader.java:136(Compiled Code)) at java/io/BufferedReader.readLine(BufferedReader.java:299(Compiled Code)) at java/io/BufferedReader.readLine(BufferedReader.java:362(Compiled Code)) at org/apache/commons/net/ftp/FTP.__getReply(FTP.java:294(Compiled Code)) at org/apache/commons/net/ftp/FTP._connectAction_(FTP.java:364(Comp iled Code)) at org/apache/commons/net/ftp/FTPClient._connectAction_(FTPClient.j ava:540(Compiled Code)) at org/apache/commons/net/SocketClient.connect(SocketClient.java:17 8(Compiled Code)) at com/ibm/wmqfte/bridge/session/ftp/FTPSession.connect(FTPSession. java:267(Compiled Code)) at com/ibm/wmqfte/bridge/session/ftp/SessionFactory.createSession(S essionFactory.java:152(Compiled Code)) at com/ibm/wmqfte/bridge/endpoint/BridgeEndPoint.createSession(Brid geEndPoint.java:79(Compiled Code)) at com/ibm/wmqfte/bridge/Bridge.createSession(Bridge.java:329(Compi led Code)) ...
Local fix
Problem summary
**************************************************************** USERS AFFECTED: This issue affects all users of WebSphere MQ Managed File Transfer who use a protocol bridge agent to connect to FTP file servers to perform file transfers. Platforms affected: MultiPlatform **************************************************************** PROBLEM DESCRIPTION: If an FTP file server became unresponsive while the protocol bridge agent was attempting to establish a connection to it, the protocol bridge agent would wait indefinitely for the FTP file server to respond after the physical TCP/IP socket had been created. When this happened, any active transfers would become blocked and no new transfers would be started.
Problem conclusion
The WebSphere MQ Managed File Transfer (MFT) protocol bridge agent has been updated to allow users to specify a time out (in seconds) that will be used when establishing a connection to an FTP file server. To set the time out for a particular FTP file server, the following attribute can be added to the limits XML element, which is a child to an FTP file server definition in the protocol bridge agent's ProtocolBridgeProperties.xml file: connectionTimeout= with a value for the number of seconds to wait when opening a socket to the FTP file server. For example, an FTP file server definition in a ProtocolBridgeProperties.xml file specifying this attribute may look as follows: timeZone="Europe/London" locale="en_GB" fileEncoding="UTF8" listFormat="unix" limitedWrite="false" > In this example, connections not successfully established to the FPT file server named "myFTPServer" within forty-five (45) seconds, are timed out and the connection attempt retried. The connectionTimeout attribute was previously only valid for SFTP file servers. After this APAR, it can be specified in the limits XML element for all file server types (FTP, FTPS and SFTP). For an FTPS server definition, a "connectTimeout" attribute can also be specified as part of the main FTPS file server definition. This is still possible, but where both the connectionTimeout attribute in the limits XML element and the connectTimeout attribute of the ftpsServer XML element is specified, the former takes precedence. For example, consider the following FTPS file server definition: timeZone="Europe/London" locale="en-GB" fileEncoding="UTF-8" listFormat="unix" limitedWrite="false" connectTimeout="30" trustStore="trustStore.jks" keyStore="ketStore.jks" > This definition is valid but the time out used on the connection would be 42 seconds. If the connectionTimeout attribute is not specified, then the protocol bridge agent will attempt to wait indefinitely when establishing an FTP connection (this is the same as specifying a time out value of 0 seconds). For FTPS and SFTP connections, a default of 30 seconds is used. --------------------------------------------------------------- The fix is targeted for delivery in the following PTFs: Version Maintenance Level v7.5 7.5.0.6 v8.0 8.0.0.4 The latest available FTE maintenance can be obtained from 'Fix List for WebSphere MQ File Transfer Edition 7.0' http://www-01.ibm.com/support/docview.wss?uid=swg27015313 The latest available MQ maintenance can be obtained from 'WebSphere MQ Recommended Fixes' http://www-1.ibm.com/support/docview.wss?rs=171&uid=swg27006037 If the maintenance level is not yet available information on its planned availability can be found in 'WebSphere MQ Planned Maintenance Release Dates' http://www-1.ibm.com/support/docview.wss?rs=171&uid=swg27006309 ---------------------------------------------------------------
Temporary fix
Comments
APAR Information
APAR number
IT07322
Reported component name
WMQ MFT
Reported component ID
5724H7242
Reported release
750
Status
CLOSED PER
PE
NoPE
HIPER
NoHIPER
Special Attention
NoSpecatt
Submitted date
2015-02-24
Closed date
2015-05-29
Last modified date
2015-06-09
APAR is sysrouted FROM one or more of the following:
APAR is sysrouted TO one or more of the following:
Fix information
Fixed component name
WMQ MFT
Fixed component ID
5724H7242
Applicable component levels
R750 PSY
UP
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Document Information
Modified date:
27 January 2022