We tried to upgrade to Jetty 9 in (cc: ), the work was done but was eventually reverted in because Jetty 9 broke h2odriver on Hadoop.
We should refactor the source code to allow use of either Jetty 8 or Jetty 9 based on the final assembly. As an alternative, we can also detect Jetty version at runtime and use the version-specific initialization sequence.
H2O standalone should come with the latest version of Jetty 8. Hadoop builds should use Jetty 8 for distributions based on Hadoop 2.x and Jetty 9 for distributions based on Hadoop 3.x.
This would benefit Sparkling Water as well.
— based on slack communication at https://h2oai.slack.com/archives/C03HXQSLW/p1539798059000100 :
support ticket is https://support.h2o.ai/helpdesk/tickets/92664
we want Jetty9 where possible, Jetty8 on older hadoops (all but CDH6)
proxy mode for CDH6 can be supported later if that is a problem