https://github.com/bobrik/ralph

Ralph is a service discovery for twemproxy on mesos
https://github.com/bobrik/ralph

Last synced: 2 months ago
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Ralph is a service discovery for twemproxy on mesos

• Host: GitHub
• URL: https://github.com/bobrik/ralph
• Owner: bobrik
• Created: 2015-03-01T14:01:21.000Z (over 9 years ago)
• Default Branch: master
• Last Pushed: 2015-03-01T16:07:12.000Z (over 9 years ago)
• Last Synced: 2024-04-14T15:52:54.806Z (2 months ago)
• Language: Go
• Size: 125 KB
• Stars: 24
• Watchers: 4
• Forks: 2
• Open Issues: 0
• Metadata Files:
  • Readme: README.md

Lists

• awesome-mesos - Ralph

README

        
# Ralph

Ralph is a service discovery for twemproxy on mesos. It allows you to run

elastic clusters of memcached and redis and change cluster sizes on

the fly without service interruption and with minimum cache loss.

## Running

Ralph uses [marathoner](https://github.com/bobrik/marathoner) to update

twemproxy configuration. You have to run marathoner updaters to use ralph.

Ralph is distributed as docker container, to run it:

```

docker run -d --net host --name ralph bobrik/ralph \

    -u marathoner-updater1:7676,marathoner-updater2:7676 -b 127.0.0.1 \

    -a '-a 0.0.0.0 -s 22222 -i 2000'

```

This would run ralph with two updaters. Ralph would publish

twemproxy pools on `127.0.0.1`. Twemproxy would publish stats

on `0.0.0.0:22222`.

Ralph is pretty lightweight to run it on every node.

## Adding pools

Your pools are managed by [marathon](https://mesosphere.github.io/marathon/),

here is an example of a pool:

```json

{

  "app": {

    "id": "/twemproxy/one",

    "cmd": "exec redis-server --port $PORT",

    "instances": 2,

    "cpus": 0.1,

    "mem": 128,

    "ports": [

      12334

    ],

    "container": {

      "type": "DOCKER",

      "volumes": [],

      "docker": {

        "image": "redis:2.8"

      }

    },

    "healthChecks": [

      {

        "path": "/",

        "protocol": "TCP",

        "portIndex": 0,

        "gracePeriodSeconds": 15,

        "intervalSeconds": 2,

        "timeoutSeconds": 5,

        "maxConsecutiveFailures": 3

      }

    ],

    "labels": {

      "twemproxy_pool": "redis_one",

      "twemproxy_distribution": "ketama",

      "twemproxy_hash": "fnv1a_64",

      "twemproxy_server_failure_limit": "10",

      "twemproxy_hash_tag": "{}",

      "twemproxy_timeout": "500",

      "twemproxy_server_retry_timeout": "8000",

      "twemproxy_redis": "true",

      "twemproxy_auto_eject_hosts": "true"

    }

  }

}

```

To expose your application with a bunch of redis or memcached servers as

twemproxy pool, you need to use application labels. To set configuration

value for your pool, just add prefix `twemproxy_` to the config key

from [twemproxy configuration](https://github.com/twitter/twemproxy#configuration)

and set it as application label. You should also set `twemproxy_pool`,

otherwise your pool will be ignored.