Manage an Application¶
Deis includes many tools for managing deployed Applications.
Scale the Application¶
Applications deployed on Deis scale out via the process model.
Use deis scale to control the number of Containers that power your app.
$ deis scale web=8
Scaling processes... but first, coffee!
done in 20s
=== peachy-waxworks Processes
--- web:
web.1 up (v2)
web.2 up (v2)
web.3 up (v2)
web.4 up (v2)
web.5 up (v2)
web.6 up (v2)
web.7 up (v2)
web.8 up (v2)
Scaling is managed by process types like web or worker defined in a
Procfile in the root of your application repository.
Note
Docker applications can use the cmd process type to scale the default container command.
Administer the Application¶
Deis applications use one-off processes for admin tasks like database migrations and other commands that must run against the live application.
Use deis run to execute commands on the deployed application.
$ deis run 'ls -l'
Running `ls -l`...
total 28
-rw-r--r-- 1 root root 553 Dec 2 23:59 LICENSE
-rw-r--r-- 1 root root 60 Dec 2 23:59 Procfile
-rw-r--r-- 1 root root 33 Dec 2 23:59 README.md
-rw-r--r-- 1 root root 1622 Dec 2 23:59 pom.xml
drwxr-xr-x 3 root root 4096 Dec 2 23:59 src
-rw-r--r-- 1 root root 25 Dec 2 23:59 system.properties
drwxr-xr-x 6 root root 4096 Dec 3 00:00 target
Troubleshoot the Application¶
Applications deployed on Deis treat logs as event streams. Deis aggregates stdout and stderr from every Container making it easy to troubleshoot problems with your application.
Use deis logs to view the log output from your deployed application.
$ deis logs | tail
Dec 3 00:30:31 ip-10-250-15-201 peachy-waxworks[web.5]: INFO:oejsh.ContextHandler:started o.e.j.s.ServletContextHandler{/,null}
Dec 3 00:30:31 ip-10-250-15-201 peachy-waxworks[web.8]: INFO:oejs.Server:jetty-7.6.0.v20120127
Dec 3 00:30:31 ip-10-250-15-201 peachy-waxworks[web.5]: INFO:oejs.AbstractConnector:Started SelectChannelConnector@0.0.0.0:10005
Dec 3 00:30:31 ip-10-250-15-201 peachy-waxworks[web.6]: INFO:oejsh.ContextHandler:started o.e.j.s.ServletContextHandler{/,null}
Dec 3 00:30:31 ip-10-250-15-201 peachy-waxworks[web.7]: INFO:oejsh.ContextHandler:started o.e.j.s.ServletContextHandler{/,null}
Dec 3 00:30:31 ip-10-250-15-201 peachy-waxworks[web.6]: INFO:oejs.AbstractConnector:Started SelectChannelConnector@0.0.0.0:10006
Dec 3 00:30:31 ip-10-250-15-201 peachy-waxworks[web.8]: INFO:oejsh.ContextHandler:started o.e.j.s.ServletContextHandler{/,null}
Dec 3 00:30:31 ip-10-250-15-201 peachy-waxworks[web.7]: INFO:oejs.AbstractConnector:Started SelectChannelConnector@0.0.0.0:10007
Dec 3 00:30:31 ip-10-250-15-201 peachy-waxworks[web.8]: INFO:oejs.AbstractConnector:Started SelectChannelConnector@0.0.0.0:10008
Limit the Application¶
Deis supports restricting memory and CPU shares of each Container.
Use deis limits:set to restrict memory by process type:
$ deis limits:set web=512M
Applying limits... done, v3
=== peachy-waxworks Limits
--- Memory
web 512M
--- CPU
Unlimited
You can also use deis limits:set -c to restrict CPU shares.
CPU shares are on a scale of 0 to 1024, with 1024 being all CPU resources on the host.
Important
If you restrict resources to the point where containers do not start, the limits:set command will hang. If this happens, use CTRL-C to break out of limits:set and use limits:unset to revert.
Isolate the Application¶
Deis supports isolating applications onto a set of hosts using tags.
Note
In order to use tags, you must first launch your hosts with the proper key/value tag information. If you do not, tag commands will fail. Learn more by reading the machine metadata section of Fleet documentation.
Once your hosts are configured with appropriate key/value metadata, use
deis tags:set to restrict the application to those hosts:
$ deis tags:set environ=prod
Applying tags... done, v4
environ prod