# The Apache Tomcat Connector

## Changelog

Preface

> This is the Changelog for Tomcat Connectors. This changelog does not contain all updates and fixes to the Tomcat connectors (yet). It should contain fixes made only after November 10th 2004, when the new documentation project for JK was started.

Changes in the released JK 1.2.19

> Native

> > | LB: Combine ok/error/recovering/busy runtime states into a single scalar. LB: Combine active/disabled/stopped configuration states into a single scalar.
> > | LB: Add several Apache notes to enable standard logging for load balancer results.
> > | LB: Reorganisation of the main load balancer service loop. (rjung)
> > | Implement hierarchical worker configuration via attribute "reference". (rjung)
> > | Log deprecated properties. (rjung)
> > | IIS: Fix simple_rewrite for the cases where the rewritten url is larger then the original one. (mturk)
> > | New JkOption to disable connection persistence. (jim)
> > | LB: Move sessionid retrieval out of get_most_suitable_worker into service. (rjung)
> > | Code cleanup for all service methods (use TRACE, JK_LOG_NULL_PARAMS, null pointer checks). (rjung)
> > | JKSTATUS: add refresh link. No refresh for updates. Redirect to list view after update. (rjung)
> > | Add new hook add_log_items into servers. (rjung)
> > | APACHE httpd: Rename apache logging notes. (rjung)
> > | LB: Rename lock and method constants. Add constants for defaults. (rjung)
> > | Default log level should be INFO and not DEBUG. Default log level should be the same for all server types. (rjung)
> > | Make rewrite_rule_map and log_level as non mandatory directives for isapi_redirect. (mturk)
> > | 40107: Rewrite is_socket_connected function. Non blocking socket is not used any more. (mturk)
> > | Allow building with VS2005 without too many warnings. (mturk)
> > | Decide by MMN, which piped log API we should use. mod_jk 1.2.18 broke compilation with Apache 1.3 pre 1.3.28. (rjung)

Changes in the released JK 1.2.18

> Native

> > | Using socklen_t in getsockopt. Also introducing jk_sock_t. (mturk)
> > | Allow recovery wait time below 60 seconds (new minimum is 1 second). (mturk)

Changes in JK 1.2.17

> Native

> > | Fix hanging jk status worker when certain attributes are being updated due to double locking. (rjung)
> > | Allow JkMount to behave like uriworkermap.properties by parsing pipe symbol as two directive marker. (mturk)

Changes in JK 1.2.16

> Native

> > | Added simple rewrite capability for IIS. Although simple it will fulfill most needs. (mturk)
> > | Added RECOVER_ABORT_IF_CLIENTERROR recovery_option that closes the connection if client connection is broken during the request. (mturk)
> > | Renamed cache_timeout directive to connection_pool_timeout. (mturk)
> > | Added connection_pool_minsize directive. (mturk)
> > | Deprecate recycle_timeout directive. (mturk)
> > | Corrected some HTML syntax bugs in output of status worker. (rjung)
> > | Added the refresh=n parameter to the status worker. It will update the display every n seconds. (rjung)
> > | Balancer: Add attribute distance to balanced workers to express preferences between workers. (rjung)
> > | Balancer: Add attribute jvm_route to balanced workers to be able to use the same target in different balancers. (rjung)
> > | Status: Add lb_mult to status. (rjung)
> > | Balancer: Make different balancing strategies work in a similar way (use lb_value, use decay during global maintenance, use integer factors for weights. (rjung)
> > | Balancer: Improve locking. (rjung)
> > | Balancer: Workers start slower after recovering. (rjung)
> > | Balancer: Make different balancing strategies work in a similar way (use lb_value, use decay during global maintenance, use integer factors lb_mult for weights). (rjung)
> > | Balancer: Move recovery check to global maintenance. (rjung)
> > | Balancer: Add global maintenance method, that is called in only one process. (rjung)
> > | Extend our use of autoconf to find a 32Bit and a 64Bit unsigned type and their printf formats. (rjung)
> > | Logging: piped loggers for JkLogFile and Apache 1.3. (rjung)
> > | Logging: Add PID to log lines for each log level apart from REQUEST. (rjung)
> > | Logging: flush buffered logs to keep lines in correct order. Output final newline together with log message. (rjung)
> > | Reducing shm size. (rjung)
> > | Only log removing of old worker, when we actually do it. (rjung)
> > | 37469: Fix shared memory close for forked childs. The shared memory will be closed by the parent process. (mturk)
> > | 37332: Fix potential misuse of buffer length with snprintf functions. (mturk)
> > | 38859: Protect mod_jk against buggy or malicious AJP servers in the backend. Patch provided by Ruediger Pluem. (mturk)
> > | 38889: Use worker map sorting depending on the path elements, to comply with Servlet spec. Patch provided by Steve Revilak. (mturk)
> > | 36138: Added Busyness lb method. Patch provided by Chris Lamprecht. (mturk)
> > | Fix pessimistic locking mode. The patch correctly handles the burst load, by syncing the access to the shared memory data. (mturk)
> > | 38806: Reclycle worker even if it is disabled. This fixes hot-standby workers in error state. (mturk)
> > | 37167: Allow building with BSD-ish like make. (mturk)
> > | ISAPI plugin (isapi_redirect.dll) did not provide correct request data for IIS to include in the IIS log. (markt)

Changes from the released JK 1.2.15

> Native

> > | Fix AJP13 Cookie2 parsing. Cookie2 was always send as Cookie. Patch provided by Andre Gebers. (mturk)
> > | 35862: NSAPI plugin attempts to read freed memory and attempts to dereference a null pointer. Patch provided by Brian Kavanagh. (markt)

Changes from the released JK 1.2.14

> Native

> > | Fix lb for worker mpm's with cachesize set to lower number then ThreadsPerChild is. If retries is set to value larger then 3 sleep for 100 ms on each attempt. This enables to tune the connection cache, and serialize incoming connections instead returning busy if connection count is larger then cachesize. (mturk)
> > | 36525: Solaris core dump. (mturk)
> > | 36102: Worker actions do not persist. (mturk)
> > | 35864: Status worker doesn't list workers. Patch provided by Martin Goldhahn. (mturk)
> > | 35809: JkMountCopy don't work for Apache 2.0 Patch provided by Christophe Dubach. (mturk)
> > | 35298: Multiple JK/ISAPI redirectors on a single IIS site are not supported Patch provided by Tim Whittington. (mturk)

Changes from the released JK 1.2.13

> Native

> > | 34397: Emergency was handled as Error. (jfclere)
> > | 34474: // in URL were not handled correctly with Apache-1.3. (jfclere)
> > | Use 64 bits int for transferred/read bytes.
> > | Added JkOptions +FlushPackets used to optimize memory usage when sending large data. (mturk)
> > | Added lock directive for load balancer that allows more acurate load balancing in case of burst load. (mturk)
> > | Added worker.maintain directive to allow customizing default 10 second timeout. On busy servers this value needs to be set on higher value. (mturk)
> > | Fix for NetWare compiler to deal with different types between AP13 and AP2 SDKs. (fuankg)
> > | Emit much more legible user.dmp crash analysis output for WIN32. (wrowe)
> > | 34558: Fix first failover request. (mturk)

Changes from the released JK 1.2.12

> Native

> > | Added ForwardLocallAddres JkOptions flag for passing local instead remote address. Useful for remote addr valve. (mturk)
> > | Fix that worker not used, when stopped flag is true. (pero)
> > | Add loadbalance default worker secret attribute to the documentation (pero)

Changes from the released JK 1.2.11

> Native

> > | Backport SC_M_JK_STORED from JK2 for passing arbitrary methods instead failing the request. (mturk)
> > | Added missing SEARCH and ACL http methods. (mturk)
> > | Add worker secret attribute to the documentation (pero)
> > | Add a stopped flag to worker configuration. Set flag True and complete traffic to worker is stopped. Also update the Ant JkStatusUpdateTask at Tomcat 5.5.10 release. Only usefull in a replicated session cluster.(pero)
> > | Added worker maintain function that will maintain all the workers instead just the current one. This enables to recycle the connections on all workers. (mturk)
> > | Use shutdown when recycling connections instead hard breaking the socket. (mturk)
> > | Add unique directives checking. The directives if unique are now overwritten instead concatenated. (mturk)
> > | Allow multiple worker.list directives. (mturk)
> > | 34577: For IIS log original request instead loging the request for ISAPI extension. (mturk)
> > | 34558: Make sure the returned status codes are the same for ajp and lb workers. (mturk)
> > | 34423: Use APR_USE_FLOCK_SERIALIZE for setting log lock on platforms like FreeBSD. Patch provided by Allan Saddi. (mturk)
> > | 33843: Fix obtaining LDFLAGS that were used for building Apache HTTPD. Patch provided by Beat Kneubuehl. (mturk)
> > | 34358: Enable load balancer method configuration. (glenn)
> > | 34357: In some situations Apache 2 mod_jk could segfault when the JkAutoAlias directive is used. (glenn)
> > | Add --enable-prefork to the documentation (pero)

Changes from the released JK 1.2.10

> Native

> > | Set default shared memory to 64K instead 1M. (mturk)
> > | Do not mark the worker in error state if headers are larger then AJP13 limit. (mturk)
> > | On Series you should use the latest PTF for Apache 2.0 (which is now 2.0.52) and ad minima SI17402/SI17061 or cumulative including them. (hgomez)
> > | Change the xml status format to xml attribute syntax (pero)
> > | 33248: Fix builds where apxs defines multiple directories for APR includes. (mturk)
> > | 32696: Return 404 instead 403 when WEB-INF is requested to comply with Servlet spec. (mturk)
> > | Added ANT task for managing jkstatus. (pero)
> > | If socket_timeout is set, check if socket is alive before sending any request to Tomcat. (mturk)
> > | Added JkMountFile for Apache web servers. This file can contain uri mappings in the form (/url=worker), and is checked for updates at regular 60 second interval. (mturk)
> > | Added status worker for managing worker runtime data using web page. (mturk)
> > | Added load balancer method directive that is used for setting the algorithm used for balancing workers. Method can be either Request (default) or Traffic. (mturk)
> > | Added shared memory to allow dynamic configuration. Shared memory is needed only for unix platform and web servers having multiple child processes. For Apache web server two new directives has been added (JkShmFile and JkShmSize). (mturk)
> > | Added textupdate mode to status worker to handle remote updates from ant tasks.(pero)
> > | 33562: Fix Reply_timeout when recovery_options is larger than 1. Patch provided by Takashi Satou. (mturk)
> > | 33308: Fix segfaults when ForwardDirectories is enabled with Apache 1.3

Changes from the released JK 1.2.8

> Native

> > | Allow anyone to debug and diagnose stack dumps using windbg or any other debugging tool, and (if they add the .pdb files to their installation) to make sense of dr watson logs. Patch provided by William A. Rowe (wrowe)
> > | Fix in_addr_t usage by using the real struct ignoring typedef. Patch provided by William A. Rowe (wrowe)
> > | Fix url rewriting by restoring the in place uri from which the jsessionid was removed. (mturk)
> > | Make load balancer algorithm thread safe by introducing mutex to the load balancer worker. (mturk)
> > | Fix sending error pages for IIS to client by adding Content-Type header using correct api function call. (mturk)
> > | 32696: Prevent IIS from crushing when web-inf url was requested. (mturk)
> > | Use default cachesize for servers that support discovering the number of threads per child process. (mturk).
> > | Fix Apache content-length header parsing using case insensitive compare. (billbarker)
> > | Fix parsing AJP headers using case insensitive compare. (mturk)
> > | Use infinite socket timeout if socket_timeout is set to zero or less then zero. (mturk)
> > | Change balanced_workers to balance_workers but keep backward compatibility preserving the old directive. (mturk).
> > | Fix ajp initialization for workers with cache_size set to zero. (mturk)
> > | 32317: Making mod_jk replication aware (Clustering Support). Patch provided by Rainer Jung. (mturk).
> > | 31132: Core dump when JkLogFile is missing from conf. (mturk)

Changes from the released JK 1.2.6

> Native

> > | Added new property named recover_time that can be used to change the default 60 second recover time. (mturk)
> > | Added custom retries for worker, so we don't depend on default setting. If set to a number grater then 3, it will sleep for 100ms on retry greater then 3 and then try again. (mturk)
> > | Added JkWorkerProperty directive that enables omiting workers.properties file. For example: JkWorkerProperty worker.ajp13a.port=8009. (mturk)
> > | Check all JSESSIONID cookies for a valid jvmRoute. If you have multiple Tomcats with overlapping domains, then you can get multiple cookies without a defined order. This will route correctly as long as the different domains don't have any Tomcats in common. (billbarker)
> > | Added JkUnMount directive for negative mappings that works as opposite to JkMount directives. It is used for blocking of particular URL or content type. (mturk)
> > | Added wildchar match uri mappings. One can now use JkMount to map /app/*/servlet/* or /app?/*/*.jsp. (mturk)
> > | Rewrite the logging by adding Trace options. (mturk)
> > | Added socket_timeout property that sets the timeout for the socket itself. (mturk)
> > | Changed socket_timeout property to recycle_timeout. This better explains what the directive actually does. (mturk)

> > Changed the load balancer algorithm. The idea behind this new scheduler is the following: lbfactor is how much we expect this worker to work, or the worker's work quota. lbstatus is how urgent this worker has to work to fulfill its quota of work. We distribute each worker's work quota to the worker, and then look which of them needs to work most urgently (biggest lbstatus). This worker is then selected for work, and its lbstatus reduced by the total work quota we distributed to all workers. Thus the sum of all lbstatus does not change.(*) If some workers are disabled, the others will still be scheduled correctly. (mturk)

JK 2

> JK2 has been put in maintainer mode and no further development will take place. The reason for shutting down JK2 development was the lack of developers interest. Other reason was lack of users interest in adopting JK2, caused by configuration complexity when compared to JK.

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