backend.ai-agent 1.2.1

Backend.AI Agent

The Backend.AI Agent is a small daemon that reports the status of a worker computer (either a physical server or a virtualized cloud instance) to the manager and performs computation requests assigned by the manager.

Package Structure

• ai.backend

  • agent: The agent daemon implementation

Installation

Backend.AI Agent requires Python 3.6 or higher. We highly recommend to use pyenv for an isolated setup of custom Python versions that might be different from default installations managed by your OS or Linux distros.

pip install backend.ai-agent

For development

We recommend to use an isolated virtual environment. This installs the current working copy and backend.ai-common as “editable” packages.

git clone https://github.com/lablup/backend.ai-agent.git
python -m venv /home/user/venv
source /home/user/venv/bin/activate
pip install -U pip setuptools   # ensure latest versions
pip install -U -r requirements-dev.txt

Deployment

Running from a command line

The minimal command to execute:

python -m ai.backend.agent.server --etcd-addr localhost:2379 --namespace my-cluster

The agent reads most configurations from the given etcd v3 server where the cluster administrator or the Backend.AI manager stores all the necessary settings.

The etcd address and namespace must match with the manager to make the agent paired and activated. By specifying distinguished namespaces, you may share a single etcd cluster with multiple separate Backend.AI clusters.

By default the agent uses /var/cache/scratches directory for making temporary home directories used by kernel containers (the /home/work volume mounted in containers). Note that the directory must exist in prior and the agent-running user must have ownership of it. You can change the location by --scratch-root option.

For more arguments and options, run the command with --help option.

Example config for agent server/instances

/etc/supervisor/conf.d/agent.conf:

[program:backend.ai-agent]
user = user
stopsignal = TERM
stopasgroup = true
command = /home/user/run-agent.sh

/home/user/run-agent.sh:

#!/bin/sh
source /home/user/venv/bin/activate
exec python -m ai.backend.agent.server \
     --etcd-addr localhost:2379 \
     --namespace my-cluster

Networking

Basically all TCP ports must be transparently open to the manager. The manager and agent should run in the same local network or different networks reachable via VPNs.

The operation of agent itself does not require both incoming/outgoing access to the public Internet, but if the user’s computation programs need, the docker containers should be able to access the public Internet (maybe via some corporate firewalls).

Several optional features such as automatic kernel image updates may require outgoing public Internet access from the agent as well.