We want your experience with Elastic Cloud Enterprise to be a success, so we compiled a list of tried-and-tested prerequisites that will help get your installation off to a good start. To make it easier to look through these prerequisites, we separated them into sections for hardware, software, users, networking, and JVM Heap Sizes.

Hardware

ECE has specific hardware requirements for memory and storage. We have compiled information for the minimums required to install ECE, recommended minimums, and specific deployment scenarios.

¹ Allocators must be sized to support your Elasticsearch clusters and Kibana instances. We recommend host machines that provide between 128 GB and 256 GB of memory. Smaller hosts might not pack larger Elasticsearch clusters and Kibana instances as efficiently. Larger hosts might provide fewer CPU resources per GB of RAM on average.

² For high availability, requires three hosts each of the capacities indicated, spread across three availability zones.

³ For high availability, requires three hosts each of the capacities indicated (except for allocators), spread across three availability zones. For allocators, requires three or more hosts of the capacity indicated, spread across three availability zones.

There are some additional hardware requirements to make sure that Elastic Cloud Enterprise can work as intended, such as the requirement to use fast SSD storage for ECE management services. To learn more, see Choose the Right Host Machines.

The size of your ECE deployment has a bearing on the JVM heap sizes that you should specify during installation. To learn more, see JVM Heap Sizes. For examples, see the deployment scenarios in our Playbook for Production.

¹ For example, if you use a host with 256 GB of RAM and the default ratio of 1:32, your host must provide 8192 GB of disk space.

Software

The following software has been tested to work with ECE:

ECE is certified for Linux kernel 3.10 or higher and Docker 1.11. The latter is the only version of Docker Elastic recommends.

If you intend to use Docker 1.12 or higher, please note:

Users

The following users and permissions are required:

You can find out information about a user with the id command:

id
uid=1000(elastic) gid=1000(elastic) groups=1000(elastic),4(adm),20(dialout),24(cdrom),25(floppy),27(sudo),29(audio),30(dip),44(video),46(plugdev),102(netdev),112(libvirtd),1001(docker)

In this example, the user elastic with a UID and GID of 1000 belongs to both the sudo and the docker groups.

Networking

The first host you install ECE on initially requires the ports for all roles to be open, which includes the ports for the coordinator, allocator, director, and proxy roles. After you have brought up your initial ECE installation, only the ports for the roles that the initial host continues to hold need to remain open.

The following networking or internet access is required for ECE:

A typical ECE installation should be contained within a single data center. We recommend that ECE installations not span different data centers, due to variations in networking latency and bandwidth that cannot be controlled.

Installation of ECE across multiple data centers might be feasible with sufficiently low latency and high bandwidth, with some restrictions around what we can support. Based on our experience with our hosted Elastic Cloud service, the following is required:

If you choose to deploy a single ECE installation across multiple data centers, you might need to contend with additional disruptions due to bandwidth or latency issues. Both ECE and Elasticsearch are designed to be resilient to networking issues, but this resiliency is intended to handle exceptions and should not be depended on as part of normal operations. If Elastic determines during a support case that an issue is related to an installation across multiple data centers, the recommended resolution will be to consolidate your installation into a single data center, with further support limited until consolidation is complete.

JVM Heap Sizes

ECE uses default JVM heap sizes for services that work for testing. For production systems, we recommend that you install ECE according to the JVM heap size recommendations in this section. Our recommendations are based on our longstanding experience with the Elastic Cloud hosted offering and our growing experience with ECE in customer settings. Other JVM heap sizes can be left at their defaults.

For small deployments, we recommend:

For medium deployments, we recommend:

For large deployments, we recommend:

You specify the recommended JVM heap sizes with --memory-settings JVM_SETTINGS parameter when you install ECE. For examples, see the deployment scenarios in our Playbook for Production.

Elasticsearch clusters and JVM Heap Size

For Elasticsearch clusters, ECE gives 50% of the available memory to the JVM heap used by Elasticsearch, while leaving the other 50% for the operating system. This memory won’t go unused, as Lucene is designed to leverage the underlying OS for caching in-memory data structures, meaning that Lucene will happily gobble up whatever is left over. The ideal heap size is somewhere below 32 GB, as heap sizes above 32 GB become less efficient.

What these recommendations mean is that on a 64 GB cluster, we dedicate 32 GB to the Elasticsearch heap and 32 GB to the operating system in the container that hosts your cluster. If you provision a 128 GB cluster, we create two 64 GB nodes, each node with 32 GB reserved for the Elasticsearch heap and 32 GB reserved for the operating system.

For more information about why heap sizes, memory for the operating system, and the 32 GB maximum for JVMs matter, see Heap: Sizing and Swapping.