Technical Blog Post
Abstract
HTTP 503 Error -The server is currently unavailable
Body
Perhaps your AS2 transactions and/or HTTP Server adapter has been performing fine for years when suddenly you receive calls from trading partners who are unable to send you data. Your trading partners report HTTP 503 errors and you scan your http.log file and discover the following error messages:
Where do you begin to remediate this? Since this is a production environment any changes you make should be temporary and monitored closely until the storm passes. To alleviate the immediate issue, from the Administration Menu, go to Deployment > Services > Configuration and use "by service type" to locate your HTTP Server Adapters.
You can keep increasing the queue depth in small increments until your trading partners are able to successfully transmit data again. Once the dust has settled, you should re-exam your settings all together and simulate the demand in a test environment. The following four resources collectively provide a great starting point for tuning your specific environment.
Here is the general performance checklist: http://www-01.ibm.com/support/knowledgecenter/SS3JSW_5.2.0/com.ibm.help.performance_mgmt.doc/SIPM_SI_GenRecomCklist.html
This is the link to tuning queues: http://www-01.ibm.com/support/knowledgecenter/SS3JSW_5.2.0/com.ibm.help.performance_mgmt.doc/SIPM_TuningQueuesASI.html?lang=en
Here's a Developerworks article on Optimization: https://www.ibm.com/developerworks/community/files/basic/anonymous/api/library/05c221b4-72c5-4cdb-962d-6f36b98753b8/document/fe0a1bcd-472c-47b8-9cb6-ddd8f2dff52d/media/Optimization%20and%20tuning%20concepts%20on%20SI.pdf.pdf
Here's the Performance guide: ftp://ftp.software.ibm.com/software/commerce/doc/sb2bi/v5r2/SI52_Perf_Mgmt_Book.pdf
UID
ibm11121757