如何在IBM Bluemix Docker云中向容器添加卷？

Question

How can you add a data volume to a container ? What is the best practice for services with persistent data in Bluemix ?

Answer 1

You can use:

 cf ic volume create VOLNAME

to create a volume and

 cf ic run [IP_address] [-p
 PORT] [-P] [-m MEMORY] [-e ENV] [-v
 VolumeId:ContainerPath[:ro]] [--name NAME] [--link
 NAME:ALIAS] IMAGE [CMD
 [CMD ...]]

• VolumeId:ContainerPath[:ro], (Optional) Attach a volume to a container by specifying the details in the following format
• VolumeId: The volume ID or name.
• ContainerPath: The absolute path to the volume in the container.
• ro: Optional. Specifying ro makes the volume read-only instead of the default read/write.

to attach a volume to a container

More info here: https://www.ng.bluemix.net/docs/containers/doc/container_creating_ov.html#container_creating_ov
and here: https://www.ng.bluemix.net/docs/containers/doc/container_optional.html

Regards.

Answer 2

To answer to your second question "What is the best practice for services with persistent data in Bluemix" since a container is not persistent by design (restarting it will make its state reset), persistent data for a container should be saved on an external docker volume: the data saved on this kind of volume will remain untouched during container start/stop/restart, so become available to the container as soon as it restart successfully. An example to that could be a DB service like mysql: configuring your mysql instance to save the DB data on the external volume will make the data saved on the database available when restarting the container (if you leave the data saved on default container's filesystem you will lost the data when restarting the container)