Database migration 'make pool.lb_algorithm larger' fails on DevStack

[Gerard Braad]

When deploying DevStack with neutron-lbaas and octavia it fails on the alembic database migrations of octavia.

The output reads:
  File "/opt/stack/octavia/octavia/db/migration/alembic_migrations/versions/43287cd10fef_make_pool_lb_algorithm_larger.py", line 33, in upgrade
    existing_type=sa.String(255))
  File "<string>", line 8, in alter_column
  File "<string>", line 3, in alter_column
  File "/usr/lib/python2.7/site-packages/alembic/operations/ops.py", line 1414, in alter_column
  File "<string>", line 8, in alter_column

sqlalchemy.exc.InternalError: (pymysql.err.InternalError) (1832, u"Cannot change column 'lb_algorithm': used in a foreign key constraint 'fk_pool_algorithm_name'") [SQL: u'ALTER TABLE pool MODIFY lb_algorithm VARCHAR(255) NOT NULL']

The issue is reproducible after ./unstack.sh and after removing the mysql databases and rerunning ./stack.sh

Current versions of components:
  octavia 820829d36baf23cfc502fe20929687fb4ae44d4e
  neutron-lbaas 860d7b73b315227cf993cb81ac5ed66e964bd4e4
  neutron c068c3f3c115fde79b8a9aec9e13838744c85ad1

[Gerard Braad (gbraad)]

configuration used to deploy devstack

[Gerard Braad (gbraad)]

alembic error

[Gerard Braad (gbraad)]

sqlalchemy.exc.InternalError: (pymysql.err.InternalError) (1832, u"Cannot change column 'lb_algorithm': used in a foreign key constraint 'fk_pool_algorithm_name'") [SQL: u'ALTER TABLE pool MODIFY lb_algorithm VARCHAR(255) NOT NULL']

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/271178

[Gerard Braad (gbraad)]

Fetching the changeset to see if this fixes it.

[Gerard Braad (gbraad)]

[stack@devstack migration]$ alembic upgrade head
INFO [alembic.runtime.migration] Context impl MySQLImpl.
INFO [alembic.runtime.migration] Will assume non-transactional DDL.
INFO [alembic.runtime.migration] Running upgrade 6abb04f24c5 -> 43287cd10fef, Make pool.lb_algorithm larger

Fixed

[Banashankar (bkalebe)]

Devstack seems to be working fine without this change now. I am not sure what got changed.

[Gerard Braad (gbraad)]

It consistently fails on both Fedora and CentOS, using mariadb. I was going to try it out on Ubuntu to compare this.

[Banashankar (bkalebe)]

Yes I see, For me too it worked fine on ubuntu and gave the same kind of error on Centos.

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/271178
Committed: https://git.openstack.org/cgit/openstack/octavia/commit/?id=259538d92f05e923c54dcb6791b3f4ed2753fc28
Submitter: Jenkins
Branch: master

commit 259538d92f05e923c54dcb6791b3f4ed2753fc28
Author: BANASHANKAR KALEBELAGUNDI VEERA <email address hidden>
Date: Fri Jan 22 00:13:04 2016 -0800

    Change the length of name in the algorithm

    since we are updating the lenght of the
    lb_algorithm in pool table we need to change
    the name column in algorithm table as its a FK

    Closes-Bug:1536876
    Change-Id: I1183da8e4effbf84c55618aa22b82dcc359b8623