Summary of the issue
It is highly recommended for customers to upgrade to Tomcat 8.5 since Tomcat 8.0 has reached the end of support on June 30, 2018. With Apache Tomcat 8.5, Apache has introduced new features and has improved the performance. However, after the upgrade, customers may see an error similar to the following when running a Liferay application:
An invalid domain [.mydomain] was specified for this cookie.
The fix
This error is caused due to the introduction of the Rfc6265CookieProcessor in Apache Tomcat 8.5.
To remove the error and make Liferay compatible with Apache Tomcat 8.5, the following line should be added to Tomcat’s context.xml file:
<CookieProcessor className="org.apache.tomcat.util.http.LegacyCookieProcessor" />
Please note that Apache Tomcat has to be restarted for the changes to take effect.
Summary
Tomcat 8.5 provides additional security and huge performance benefits. While the benefits are significant, you have to make a few changes to preserve the behavior to mimic the older generation of Tomcat (8.0) environment.
If you have questions on how you can best leverage audience targeting and / or need help with your Liferay DXP implementation, please engage via comments on this blog post, or reach out to us.
Additional Reading
You can also continue to explore Liferay DXP by checking out the Standard deployment structure recommended by XTIVIA that makes your AppServer upgrades easier, or Steps to Follow for Overcoming HTTPS Socket Errors in JMeter, or Top 5 DevOps Features in Liferay DXP from a devops perspective.