Bug 1491268

Summary: [DOCS] Explain different options for docker-storage-setup using overlay2
Product: Red Hat Enterprise Linux 7 Reporter: Eduardo Minguez <eminguez>
Component: doc-RHEL-AtomicAssignee: Maxim Svistunov <msvistun>
Status: CLOSED CURRENTRELEASE QA Contact:
Severity: unspecified Docs Contact: Vikram Goyal <vigoyal>
Priority: high    
Version: 7.0CC: cnegus, pasik, rhel-docs, zdover
Target Milestone: pre-dev-freezeKeywords: Documentation, Extras, Reopened
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Hardware: Unspecified   
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Last Closed: 2017-12-11 11:41:37 UTC Type: Bug
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Description Eduardo Minguez 2017-09-13 12:21:00 UTC 
Document URL: https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux_atomic_host/7/html/managing_containers/managing_storage_with_docker_formatted_containers#overlay_graph_driver

Section Number and Name: 1.6. Overlay Graph Driver

Describe the issue:

There are a few variables unexplained in the documentation regarding overlay2 support for docker.
It seems overlay2 support is different than multipath, so if you specify the CONTAINER_ROOT_LV_NAME and CONTAINER_ROOT_LV_MOUNT_PATH variables, it will create a new logical volume for storing container images and container rootfs, otherwise, no new logical volume will be created and overlay2 will be setup on rootfs.

Suggestions for improvement: 
Include proper documentation about how this works and different scenarios, as it is assumed it works like multipath (it will create the lv, etc. without needed those variables)

Additional information: 
There is a related Bugzilla where you can find more information https://bugzilla.redhat.com/show_bug.cgi?id=1490910