mirror of
https://github.com/genuinetools/reg.git
synced 2024-09-12 06:11:03 -04:00
185 lines
9.3 KiB
Markdown
185 lines
9.3 KiB
Markdown
---
|
|
keywords: "API, Usage, plugins, documentation, developer"
|
|
title: Plugins and Services
|
|
---
|
|
|
|
<!-- This file is maintained within the docker/cli GitHub
|
|
repository at https://github.com/docker/cli/. Make all
|
|
pull requests against that repo. If you see this file in
|
|
another repository, consider it read-only there, as it will
|
|
periodically be overwritten by the definitive file. Pull
|
|
requests which include edits to this file in other repositories
|
|
will be rejected.
|
|
-->
|
|
|
|
# Using Volume and Network plugins in Docker services
|
|
|
|
In swarm mode, it is possible to create a service that allows for attaching
|
|
to networks or mounting volumes that are backed by plugins. Swarm schedules
|
|
services based on plugin availability on a node.
|
|
|
|
|
|
### Volume plugins
|
|
|
|
In this example, a volume plugin is installed on a swarm worker and a volume
|
|
is created using the plugin. In the manager, a service is created with the
|
|
relevant mount options. It can be observed that the service is scheduled to
|
|
run on the worker node with the said volume plugin and volume. Note that,
|
|
node1 is the manager and node2 is the worker.
|
|
|
|
1. Prepare manager. In node 1:
|
|
|
|
```bash
|
|
$ docker swarm init
|
|
Swarm initialized: current node (dxn1zf6l61qsb1josjja83ngz) is now a manager.
|
|
```
|
|
|
|
2. Join swarm, install plugin and create volume on worker. In node 2:
|
|
|
|
```bash
|
|
$ docker swarm join \
|
|
--token SWMTKN-1-49nj1cmql0jkz5s954yi3oex3nedyz0fb0xx14ie39trti4wxv-8vxv8rssmk743ojnwacrr2e7c \
|
|
192.168.99.100:2377
|
|
```
|
|
|
|
```bash
|
|
$ docker plugin install tiborvass/sample-volume-plugin
|
|
latest: Pulling from tiborvass/sample-volume-plugin
|
|
eb9c16fbdc53: Download complete
|
|
Digest: sha256:00b42de88f3a3e0342e7b35fa62394b0a9ceb54d37f4c50be5d3167899994639
|
|
Status: Downloaded newer image for tiborvass/sample-volume-plugin:latest
|
|
Installed plugin tiborvass/sample-volume-plugin
|
|
```
|
|
|
|
```bash
|
|
$ docker volume create -d tiborvass/sample-volume-plugin --name pluginVol
|
|
```
|
|
|
|
3. Create a service using the plugin and volume. In node1:
|
|
|
|
```bash
|
|
$ docker service create --name my-service --mount type=volume,volume-driver=tiborvass/sample-volume-plugin,source=pluginVol,destination=/tmp busybox top
|
|
|
|
$ docker service ls
|
|
z1sj8bb8jnfn my-service replicated 1/1 busybox:latest
|
|
```
|
|
docker service ls shows service 1 instance of service running.
|
|
|
|
4. Observe the task getting scheduled in node 2:
|
|
|
|
```bash
|
|
{% raw %}
|
|
$ docker ps --format '{{.ID}}\t {{.Status}} {{.Names}} {{.Command}}'
|
|
83fc1e842599 Up 2 days my-service.1.9jn59qzn7nbc3m0zt1hij12xs "top"
|
|
{% endraw %}
|
|
```
|
|
|
|
### Network plugins
|
|
|
|
In this example, a global scope network plugin is installed on both the
|
|
swarm manager and worker. A service is created with replicated instances
|
|
using the installed plugin. We will observe how the availability of the
|
|
plugin determines network creation and container scheduling.
|
|
|
|
Note that node1 is the manager and node2 is the worker.
|
|
|
|
|
|
1. Install a global scoped network plugin on both manager and worker. On node1
|
|
and node2:
|
|
|
|
```bash
|
|
$ docker plugin install bboreham/weave2
|
|
Plugin "bboreham/weave2" is requesting the following privileges:
|
|
- network: [host]
|
|
- capabilities: [CAP_SYS_ADMIN CAP_NET_ADMIN]
|
|
Do you grant the above permissions? [y/N] y
|
|
latest: Pulling from bboreham/weave2
|
|
7718f575adf7: Download complete
|
|
Digest: sha256:2780330cc15644b60809637ee8bd68b4c85c893d973cb17f2981aabfadfb6d72
|
|
Status: Downloaded newer image for bboreham/weave2:latest
|
|
Installed plugin bboreham/weave2
|
|
```
|
|
|
|
2. Create a network using plugin on manager. On node1:
|
|
|
|
```bash
|
|
$ docker network create --driver=bboreham/weave2:latest globalnet
|
|
|
|
$ docker network ls
|
|
NETWORK ID NAME DRIVER SCOPE
|
|
qlj7ueteg6ly globalnet bboreham/weave2:latest swarm
|
|
```
|
|
|
|
3. Create a service on the manager and have replicas set to 8. Observe that
|
|
containers get scheduled on both manager and worker.
|
|
|
|
On node 1:
|
|
|
|
```bash
|
|
$ docker service create --network globalnet --name myservice --replicas=8 mrjana/simpleweb simpleweb
|
|
w90drnfzw85nygbie9kb89vpa
|
|
```
|
|
|
|
```bash
|
|
$ docker ps
|
|
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
|
|
87520965206a mrjana/simpleweb@sha256:317d7f221d68c86d503119b0ea12c29de42af0a22ca087d522646ad1069a47a4 "simpleweb" 5 seconds ago Up 4 seconds myservice.4.ytdzpktmwor82zjxkh118uf1v
|
|
15e24de0f7aa mrjana/simpleweb@sha256:317d7f221d68c86d503119b0ea12c29de42af0a22ca087d522646ad1069a47a4 "simpleweb" 5 seconds ago Up 4 seconds myservice.2.kh7a9n3iauq759q9mtxyfs9hp
|
|
c8c8f0144cdc mrjana/simpleweb@sha256:317d7f221d68c86d503119b0ea12c29de42af0a22ca087d522646ad1069a47a4 "simpleweb" 5 seconds ago Up 4 seconds myservice.6.sjhpj5gr3xt33e3u2jycoj195
|
|
2e8e4b2c5c08 mrjana/simpleweb@sha256:317d7f221d68c86d503119b0ea12c29de42af0a22ca087d522646ad1069a47a4 "simpleweb" 5 seconds ago Up 4 seconds myservice.8.2z29zowsghx66u2velublwmrh
|
|
```
|
|
|
|
On node 2:
|
|
|
|
```bash
|
|
$ docker ps
|
|
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
|
|
53c0ae7c1dae mrjana/simpleweb@sha256:317d7f221d68c86d503119b0ea12c29de42af0a22ca087d522646ad1069a47a4 "simpleweb" 2 seconds ago Up Less than a second myservice.7.x44tvvdm3iwkt9kif35f7ykz1
|
|
9b56c627fee0 mrjana/simpleweb@sha256:317d7f221d68c86d503119b0ea12c29de42af0a22ca087d522646ad1069a47a4 "simpleweb" 2 seconds ago Up Less than a second myservice.1.x7n1rm6lltw5gja3ueikze57q
|
|
d4f5927ba52c mrjana/simpleweb@sha256:317d7f221d68c86d503119b0ea12c29de42af0a22ca087d522646ad1069a47a4 "simpleweb" 2 seconds ago Up 1 second myservice.5.i97bfo9uc6oe42lymafs9rz6k
|
|
478c0d395bd7 mrjana/simpleweb@sha256:317d7f221d68c86d503119b0ea12c29de42af0a22ca087d522646ad1069a47a4 "simpleweb" 2 seconds ago Up Less than a second myservice.3.yr7nkffa48lff1vrl2r1m1ucs
|
|
```
|
|
|
|
4. Scale down the number of instances. On node1:
|
|
|
|
```bash
|
|
$ docker service scale myservice=0
|
|
myservice scaled to 0
|
|
```
|
|
|
|
5. Disable and uninstall the plugin on the worker. On node2:
|
|
|
|
```bash
|
|
$ docker plugin rm -f bboreham/weave2
|
|
bboreham/weave2
|
|
```
|
|
|
|
6. Scale up the number of instances again. Observe that all containers are
|
|
scheduled on the master and not on the worker, because the plugin is not available on the worker anymore.
|
|
|
|
On node 1:
|
|
|
|
```bash
|
|
$ docker service scale myservice=8
|
|
myservice scaled to 8
|
|
```
|
|
|
|
```bash
|
|
$ docker ps
|
|
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
|
|
cf4b0ec2415e mrjana/simpleweb@sha256:317d7f221d68c86d503119b0ea12c29de42af0a22ca087d522646ad1069a47a4 "simpleweb" 39 seconds ago Up 36 seconds myservice.3.r7p5o208jmlzpcbm2ytl3q6n1
|
|
57c64a6a2b88 mrjana/simpleweb@sha256:317d7f221d68c86d503119b0ea12c29de42af0a22ca087d522646ad1069a47a4 "simpleweb" 39 seconds ago Up 36 seconds myservice.4.dwoezsbb02ccstkhlqjy2xe7h
|
|
3ac68cc4e7b8 mrjana/simpleweb@sha256:317d7f221d68c86d503119b0ea12c29de42af0a22ca087d522646ad1069a47a4 "simpleweb" 39 seconds ago Up 35 seconds myservice.5.zx4ezdrm2nwxzkrwnxthv0284
|
|
006c3cb318fc mrjana/simpleweb@sha256:317d7f221d68c86d503119b0ea12c29de42af0a22ca087d522646ad1069a47a4 "simpleweb" 39 seconds ago Up 36 seconds myservice.8.q0e3umt19y3h3gzo1ty336k5r
|
|
dd2ffebde435 mrjana/simpleweb@sha256:317d7f221d68c86d503119b0ea12c29de42af0a22ca087d522646ad1069a47a4 "simpleweb" 39 seconds ago Up 36 seconds myservice.7.a77y3u22prjipnrjg7vzpv3ba
|
|
a86c74d8b84b mrjana/simpleweb@sha256:317d7f221d68c86d503119b0ea12c29de42af0a22ca087d522646ad1069a47a4 "simpleweb" 39 seconds ago Up 36 seconds myservice.6.z9nbn14bagitwol1biveeygl7
|
|
2846a7850ba0 mrjana/simpleweb@sha256:317d7f221d68c86d503119b0ea12c29de42af0a22ca087d522646ad1069a47a4 "simpleweb" 39 seconds ago Up 37 seconds myservice.2.ypufz2eh9fyhppgb89g8wtj76
|
|
e2ec01efcd8a mrjana/simpleweb@sha256:317d7f221d68c86d503119b0ea12c29de42af0a22ca087d522646ad1069a47a4 "simpleweb" 39 seconds ago Up 38 seconds myservice.1.8w7c4ttzr6zcb9sjsqyhwp3yl
|
|
```
|
|
|
|
On node 2:
|
|
|
|
```bash
|
|
$ docker ps
|
|
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
|
|
```
|