Presto 101t Documentation

Presto-Admin Configuration

Presto-Admin Configuration

A Presto cluster consists of a coordinator node and one or more workers nodes. A coordinator and worker may be located on the same node, meaning that you can have a single-node installation of Presto, but having a dedicated node for the coordinator is recommended for better performance, especially on larger clusters.

In order to use presto-admin to manage software on a cluster of nodes, you must specify a configuration for presto-admin. This configuration indicates the nodes on which to install as well as other credentials.

To set up a configuration, create a file /etc/opt/prestoadmin/config.json with the content below. Replace the variables denoted with brackets <> with actual values enclosed in quotations. The user specified by username must have sudo access on all of Presto nodes, and presto-admin also must be able to login to all of the nodes via SSH as that user (see SSH Configuration for details on how to set that up). The file should be owned by root with R/W permissions (i.e. 622).

"username": "<ssh_user_name>",
"port": "<ssh_port>",
"coordinator": "<host_name>",
"workers": ["<host_name_1>", "<host_name_2>", ... "<host_name_n>"]

All of the properties are optional. If you include a blank config.json file, the following default configuration is used:

"username": "root",
"port": "22",
"coordinator": "localhost",
"workers": ["localhost"]

The above configuration is for a single-node installation of Presto on the same node that presto-admin is installed on. You can also specify some but not all of the properties. For example, for a 6 node cluster with default username and port, a sample config.json would be:

"coordinator": "master",
"workers": ["slave1","slave2","slave3","slave4","slave5"]

Sudo Password Specification

Please note that if the username you specify is not root, and that user needs to specify a sudo password, you do so in one of two ways. You can specify it on the command line:

sudo ./presto-admin <command> -p <password>

Alternatively, you can opt to use an interactive password prompt, which prompts you for the initial value of your password before running any commands:

sudo ./presto-admin <command> -I
Initial value for env.password: <type your password here>

The sudo password for the user must be the same as the SSH password.