the Analytics team is going to stop HDFS and Yarn services for a (hopefully) brief time window tomorrow, Tue Oct 15th, from 14:30 to 15:30 CEST.

We are going to swap the Zookeeper cluster from the one currently used by all the Kafka production services to a dedicated one within the Analytics VLAN. More details in https://phabricator.wikimedia.org/T217057

Side effects: the move should be transparent to all users, except the ones relying on history in Yarn (for example, checking it via yarn.wikimedia.org). The history is in fact stored in zookeeper, and to keep things simple we are not copying znodes over to the new cluster. Please let us know if this impacts you in any way.

As usual, if the time window affects your work please let us know and we'll find a new maintenance window.

Thanks!

Luca (on behalf of the Analytics team).