Preparing Apache Tomcat

AM examples often use Apache Tomcat (Tomcat) as the deployment container. Tomcat is installed on, and listens on the default ports without a Java Security Manager enabled.

JVM start up

AM core services require a minimum JVM heap size of 1 GB, and a metadata space size of up to 256 MB. If you are evaluating AM and using the embedded DS, you require at least a 2 GB heap, as 50% of that space is allocated to DS. See "Preparing a Java Environment" for details.

Set a CATALINA_OPTS environment variable with the appropriated tuning for your environment. For example, add the following in the $CATALINA_BASE/bin/ file:

export CATALINA_OPTS="$CATALINA_OPTS -server -Xmx2g -XX:MetaspaceSize=256m -XX:MaxMetaspaceSize=256m"

Some versions of Internet Explorer and Microsoft Edge support the Expires header attribute instead of the Max-Age header attribute, which may cause SAML v2.0 and agent logout sequences to fail.

If you have set the org.apache.catalina.STRICT_SERVLET_COMPLIANCE Tomcat property to true, add the org.apache.tomcat.util.http.ServerCookie.ALWAYS_ADD_EXPIRE property in the $CATALINA_BASE/bin/ file, to add the Expires attribute to the headers:

export CATALINA_OPTS="$CATALINA_OPTS -server -Xmx2g -XX:MetaspaceSize=256m -XX:MaxMetaspaceSize=256m \

Slashes in Resource Names

Some AM resources have names that can contain slash characters (/), for example, in policy names, application names, and SAML v2.0 entities. These slash characters can cause unexpected behavior when running AM on Tomcat.

One possible workaround is to configure Tomcat to allow encoded slash characters by adding the org.apache.tomcat.util.buf.UDecoder.ALLOW_ENCODED_SLASH=true property to the CATALINA_OPTS variable; however, this is not recommended for production deployments (see the warning below). For example:

  export CATALINA_OPTS="$CATALINA_OPTS -server -Xmx2g -XX:MetaspaceSize=256m -XX:MaxMetaspaceSize=256m \


It is strongly recommended that you do not enable org.apache.tomcat.util.buf.UDecoder.ALLOW_ENCODED_SLASH when running AM in production as it introduces a security risk.

For more information, see How do I safely enable the org.apache.tomcat.util.buf.UDecoder.ALLOW_ENCODED_SLASH setting in AM/OpenAM (All Versions)? in the ForgeRock Knowledge Base.

Cookie Domains

You can set the cookie domain name value to an empty string for host-only cookies or to any non-top level domain. For example, if you install AM and use as the host, you can set the cookie domain name as For information about configuring the cookie domain during installation, see "To Configure an Instance".

Encoding and Security

ForgeRock recommends that you edit the Tomcat <Connector> configuration to set URIEncoding="UTF-8". UTF-8 URI encoding ensures that URL-encoded characters in the paths of URIs are correctly decoded by the container. This is particularly useful if your applications use the AM REST APIs and some identifiers, such as user names, contain special characters.

You should also ensure the sslProtocol property is set to TLS, which disables the potentially vulnerable SSL v3.0 protocol.

<Connector> configuration elements are found in the configuration file, /path/to/tomcat/conf/server.xml. The following excerpt shows an example <Connector> with the URIEncoding and sslProtocol attributes set appropriately:

<Connector port="8443" protocol="HTTP/1.1" SSLEnabled="true"
 maxThreads="150" scheme="https" secure="true"
 clientAuth="false" sslProtocol="TLS" URIEncoding="UTF-8" />

When you have finished setting up Apache Tomcat, ForgeRock recommends that you enforce HTTPS connections to AM. For more information, see "Configuring AM's Container for HTTPS".

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