Not enough space for generating the backup using 'dockerctl backup'

[Vladimir Khlyunev]

ISO 9.0-164

Steps to reproduce:
1) Deploy 9.0 fuel
2) (optional) - Deploy any cluster
3) On master node run "dockerctl backup" without args
OR
3) On master node run "dockerctl backup /root"

Result:
Saving containers to combined archive...
time="2016-02-01T12:03:20Z" level=debug msg="[stream] End of stdout"
write /dev/stdout: no space left on device
OR
tar: /var/log/fuel_backup_2016-02-01_1032.tar: Wrote only 2048 of 10240 bytes

It looks like there is not enough space for generating the archive:
df -h before backup:
/dev/mapper/os-root 9.5G 1.4G 7.6G 16% /
/dev/mapper/os-var 9.5G 5.3G 3.8G 59% /var

But when I used /var/log for generating the backup - all is fine.
/dev/mapper/os-varlog 32G 4.1G 27G 14% /var/log

Snapshot is not available due to exhausted space in /var directory.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/274657

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: stable/8.0
Review: https://review.openstack.org/274896

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/274657
Committed: https://git.openstack.org/cgit/openstack/fuel-main/commit/?id=10b609078e81b3fc704ac8aa39f41c463c56af76
Submitter: Jenkins
Branch: master

commit 10b609078e81b3fc704ac8aa39f41c463c56af76
Author: Matthew Mosesohn <email address hidden>
Date: Mon Feb 1 16:36:49 2016 +0300

    Balance /var and /var/log disk partitions

    Prior to Fuel 8.0, there was a balance of the
    following directories for remaining space:
    /var, /var/lib/docker, /var/log

    Now docker has its own pv, and /var/log was
    incorrectly given all the remaining space,
    leaving /var fixed at 10GB.

    The new balance is as follows:
    docker pv: 20gb
    /: 10gb fixed size
    /var: 40% of remaining space
    /var/log: 60% of remaining space

    Also raised minimum disk space requirement to
    45GB. This reflects the actual minimum sizes
    so that a user receives the error before partitioning
    and is properly informed.

    Change-Id: Id283e7dd4b94d5f6e1eb8397af33fea2b9f985f7
    Closes-Bug: #1540331

[Matthew Mosesohn (raytrac3r)]

This bug will be merged for HCF tomorrow.

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/274896
Committed: https://git.openstack.org/cgit/openstack/fuel-main/commit/?id=c5aac6c0b8d2a37147fdd6e6b78df4ad2ad90e31
Submitter: Jenkins
Branch: stable/8.0

commit c5aac6c0b8d2a37147fdd6e6b78df4ad2ad90e31
Author: Matthew Mosesohn <email address hidden>
Date: Mon Feb 1 16:36:49 2016 +0300

    Balance /var and /var/log disk partitions

    Prior to Fuel 8.0, there was a balance of the
    following directories for remaining space:
    /var, /var/lib/docker, /var/log

    Now docker has its own pv, and /var/log was
    incorrectly given all the remaining space,
    leaving /var fixed at 10GB.

    The new balance is as follows:
    docker pv: 20gb
    /: 10gb fixed size
    /var: 40% of remaining space
    /var/log: 60% of remaining space

    Also raised minimum disk space requirement to
    45GB. This reflects the actual minimum sizes
    so that a user receives the error before partitioning
    and is properly informed.

    Change-Id: Id283e7dd4b94d5f6e1eb8397af33fea2b9f985f7
    Closes-Bug: #1540331

[Dmitriy Kruglov (dkruglov)]

Docker removal in 9.0 makes the original scenario not applicable for MOS 9.0.