glance-api yoga loads unnecessary configuration files

[Rikimaru Honjo]

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Issue
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I'm using glance-api yoga of cloud-archive on Ubuntu 20.04.

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# dpkg -l|grep glance-api
ii glance-api 2:24.1.0-0ubuntu1~cloud0 all OpenStack Image Registry and Delivery Service - API
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I set use_syslog=True in glance-api.conf. But it didn't work. The glance-api's log messages weren't printed in syslog.

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Root cause
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The "config-dir" option[1] is specified for glance-api processes.

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# ps -ef|grep glance
glance 174533 1 2 08:55 ? 00:00:21 /usr/bin/python3 /usr/bin/glance-api --config-file=/etc/glance/glance-api.conf --config-dir=/etc/glance/ --log-file=/var/log/glance/glance-api.log
glance 174561 174533 0 08:55 ? 00:00:00 /usr/bin/python3 /usr/bin/glance-api --config-file=/etc/glance/glance-api.conf --config-dir=/etc/glance/ --log-file=/var/log/glance/glance-api.log
glance 174562 174533 0 08:55 ? 00:00:00 /usr/bin/python3 /usr/bin/glance-api --config-file=/etc/glance/glance-api.conf --config-dir=/etc/glance/ --log-file=/var/log/glance/glance-api.log
root 180241 180002 0 09:12 pts/0 00:00:00 grep --color=auto glance
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So glance-api loads all *.conf files under the /etc/glance directory. As a result, /etc/glance/rootwrap.conf's use_syslog value(False) overwrites glance-api.conf's use_syslog value(True). The *.conf files seem to be loaded in alphabetical order.

I think that glance-api also loads unnecessary configuration files.(e.g. glance-scrubber.conf, rootwrap.conf...)

The "config-dir" option is defined in /etc/init.d/glance-api.

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# grep config-dir /etc/init.d/glance-api
DAEMON_ARGS="--config-dir=/etc/${PROJECT_NAME}/"
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[1]
The config-dir spec is written in the following document.
https://docs.openstack.org/glance/latest/configuration/configuring.html

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Why is "config-dir" specified?
==============================

'DAEMON_ARGS="--config-dir=/etc/${PROJECT_NAME}/"' was added by the following bug report.

https://bugs.launchpad.net/cloud-archive/+bug/1955022

=>https://git.launchpad.net/~ubuntu-openstack-dev/ubuntu/+source/glance/commit/?id=39ce4e7eafc33ef2ddc61c338230b4afe1eeb79b

The above patch was contained in ver. 2:23.0.0+git2022011216.502fa0ffc-0ubuntu1.

So there is a possibility that this issue will also affect to xena version. But I haven't confirm xena. I would appreciate it if someone could confirm that.

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Remarks
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These are the files under /etc/glance directory after installing the glance-api yoga package.

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# ls -1 /etc/glance/
glance-api-paste.ini
glance-api.conf
glance-cache.conf
glance-image-import.conf.sample
glance-manage.conf
glance-scrubber.conf
metadefs
rootwrap.conf
rootwrap.d
schema-image.json
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