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Eric Yang commented on YARN-7935: --------------------------------- [~suma.shivaprasad] Docker embedded DNS will use /etc/resolv.conf from host, and filter out local IP addresses (127.0.0.1 etc), if no entires are available, it will route to 8.8.8.8. If RegistryDNS is listed in host machine /etc/resolv.conf, then it will be used. There is no need to manually redefine network alias or CONTAINER_HOSTNAME for spark workload to run. I don't think we can modify Hadoop code to support docker's user-defined network in 2018 because docker heavily use of NAT to accomplish user defined network. This doesn't work today with Hadoop because Hadoop only understand 1 dimensional network due to constrain check of client and server/IP mapping for preventing replay attack. Hence, the proposed feature of use --link=CONTAINER_NAME:ALIAS for docker embedded DNS might not work as well as you have hoped for Hadoop 3.x. > Expose container's hostname to applications running within the docker > container > ------------------------------------------------------------------------------- > > Key: YARN-7935 > URL: https://issues.apache.org/jira/browse/YARN-7935 > Project: Hadoop YARN > Issue Type: Sub-task > Components: yarn > Reporter: Suma Shivaprasad > Assignee: Suma Shivaprasad > Priority: Major > Attachments: YARN-7935.1.patch, YARN-7935.2.patch, YARN-7935.3.patch > > > Some applications have a need to bind to the container's hostname (like > Spark) which is different from the NodeManager's hostname(NM_HOST which is > available as an env during container launch) when launched through Docker > runtime. The container's hostname can be exposed to applications via an env > CONTAINER_HOSTNAME. Another potential candidate is the container's IP but > this can be addressed in a separate jira. -- This message was sent by Atlassian JIRA (v7.6.3#76005) --------------------------------------------------------------------- To unsubscribe, e-mail: yarn-issues-unsubscr...@hadoop.apache.org For additional commands, e-mail: yarn-issues-h...@hadoop.apache.org