Introduction

Most reconnection issues with the MSSQL Database are caused by too many TCP connections to the database. The SQL server has no free ports during the connection setup phase. The error looks like

The driver could not establish a secure connection to SQL Server by using Secure Sockets Layer (SSL) encryption.

The follow changes can reduce the number of failed connection setups for the application code:

Enable reconnect in case of a failure
Reduce the number of new connections by configuring (optimizing) the JDBC-connection pool

Enable Reconnect

Since version 9.4.0 the JDBC driver contains an additional parameter for reconnect.

The mssql-jdbc driver is updated in all LTS versions of ICM. To improve the rollout speed of the change, the project can apply a version filter to update the library without updating the whole project. Please keep in mind to remove the "patch" after migrating to the latest LTS version.

Library	Old Version	New Version
com.microsoft.sqlserver:mssql-jdbc	8.4.1.jre8	9.4.0.jre8

Following adaptions are recommended:

Property	Default	Value
connectRetryCount	1	3
connectRetryInterval	10	20
loginTimeout	15	30

See the documentation of the jdbc-driver to configure the reconnect capability.

How to get the used version

All libraries are listed at <IS_SHARE>/ivy.xml. The line can be found easily.

cat ivy.xml | grep "mssql-jdbc"

<dependency org="com.microsoft.sqlserver" name="mssql-jdbc" rev="9.4.0.jre8" conf="development-cartridges, production-cartridges, test-cartridges" transitive="false"/>

Availability in ICM versions

ICM	mssql-jdbc
7.10.26.19-LTS	9.4.0.jre8
7.10.32.9-LTS	9.4.0.jre8
7.10.37.0	9.4.0.jre8
7.10.38.3-LTS	9.4.0.jre8

Version Provider

In case the project can't update to an newer ICM soon. The version can be defined at project too. The project can declare a specific filter for project-specific dependencies, please add this section to the build.gradle of the customization. The build.gradle can contain the following block:

build.gradle

versionRecommendation {
    provider {
        // thirdparty.version to resolve version conflicts of custom cartridges
        properties('thirdparty', file('thirdparty.version')) {}
    }
}

Afterwards versions can be adapted in the Java-like property file:

thirdparty.version

com.microsoft.sqlserver:mssql-jdbc=9.4.1.jre8

The documented version of the JDBC driver could be updated meanwhile. See https://mvnrepository.com/artifact/com.microsoft.sqlserver/mssql-jdbc. Keep in mind that the version needs to have a JRE8 extension.

Configuration JDBC Connection Pool

ICM uses an Apache connection pool which has 3 important configurations:

Property	Description	old	new	for larger installations
intershop.jdbc.mssql.dbcp.pool.MaxIdle	In case the pool has more than this amount of idle connections, the pool will automatically close connections, which are "closed" by the application.	5	16	45
intershop.jdbc.mssql.dbcp.pool.MinIdle	In case the pool has less than this amount of idle connections, the pool will automatically create new connections without an explicit connection request	5	4	15
intershop.jdbc.mssql.dbcp.pool.MaxTotal	Max amount of connections handle by the pool	150	150	150

The value of MaxIdle should be significant larger than MinIdle, so that used connections can be stored in the pool without closing them. The MinIdle value can be increased in case the application needs very fast a larger amount of connections.

Transient Lock

During the staging process, the TransientLock is set for locking resources. These connection between ICM and the SQLServer can be closed by infrastructure components like network or by the SQL Server it self, in case these connections are not used for a long time. To avoid such situations the "TransientLock" can be configured with an heartbeat.

Property	Description	old	new
intershop.jdbc.connection.Heartbeat.Interval	enables and declare period between two heartbeats in seconds	0	30

ICM Adaptions

Version	Description
7.10.38.14-LTS	Changes the default of intershop.jdbc.connection.Heartbeat.Interval for TransientLock to 30

Disclaimer

The information provided in the Knowledge Base may not be applicable to all systems and situations. Intershop Communications will not be liable to any party for any direct or indirect damages resulting from the use of the Customer Support section of the Intershop Corporate Web site, including, without limitation, any lost profits, business interruption, loss of programs or other data on your information handling system.