Notice

This document is for a development version of Ceph.

Running Tests in the Cloud

In this chapter, we will explain in detail how use an OpenStack tenant as an environment for Ceph integration testing.

Assumptions and caveat

We assume that:

  1. you are the only person using the tenant

  2. you have the credentials

  3. the tenant supports the nova and cinder APIs

Caveat: be aware that, as of this writing (July 2016), testing in OpenStack clouds is a new feature. Things may not work as advertised. If you run into trouble, ask for help on IRC or the Mailing list, or open a bug report at the ceph-workbench bug tracker.

Prepare tenant

If you have not tried to use ceph-workbench with this tenant before, proceed to the next step.

To start with a clean slate, login to your tenant via the Horizon dashboard and:

  • terminate the teuthology and packages-repository instances, if any

  • delete the teuthology and teuthology-worker security groups, if any

  • delete the teuthology and teuthology-myself key pairs, if any

Also do the above if you ever get key-related errors (“invalid key”, etc.) when trying to schedule suites.

Getting ceph-workbench

Since testing in the cloud is done using the ceph-workbench ceph-qa-suite tool, you will need to install that first. It is designed to be installed via Docker, so if you don’t have Docker running on your development machine, take care of that first. You can follow the official tutorial to install if you have not installed yet.

Once Docker is up and running, install ceph-workbench by following the Installation instructions in the ceph-workbench documentation.

Linking ceph-workbench with your OpenStack tenant

Before you can trigger your first teuthology suite, you will need to link ceph-workbench with your OpenStack account.

First, download a openrc.sh file by clicking on the “Download OpenStack RC File” button, which can be found in the “API Access” tab of the “Access & Security” dialog of the OpenStack Horizon dashboard.

Second, create a ~/.ceph-workbench directory, set its permissions to 700, and move the openrc.sh file into it. Make sure that the filename is exactly ~/.ceph-workbench/openrc.sh.

Third, edit the file so it does not ask for your OpenStack password interactively. Comment out the relevant lines and replace them with something like:

.. prompt:: bash $

export OS_PASSWORD=”aiVeth0aejee3eep8rogho3eep7Pha6ek”

When ceph-workbench ceph-qa-suite connects to your OpenStack tenant for the first time, it will generate two keypairs: teuthology-myself and teuthology.

Run the dummy suite

You are now ready to take your OpenStack teuthology setup for a test drive

ceph-workbench ceph-qa-suite --suite dummy

Be forewarned that the first run of ceph-workbench ceph-qa-suite on a pristine tenant will take a long time to complete because it downloads a VM image and during this time the command may not produce any output.

The images are cached in OpenStack, so they are only downloaded once. Subsequent runs of the same command will complete faster.

Although dummy suite does not run any tests, in all other respects it behaves just like a teuthology suite and produces some of the same artifacts.

The last bit of output should look something like this:

pulpito web interface: http://149.202.168.201:8081/
ssh access           : ssh -i /home/smithfarm/.ceph-workbench/teuthology-myself.pem ubuntu@149.202.168.201 # logs in /usr/share/nginx/html

What this means is that ceph-workbench ceph-qa-suite triggered the test suite run. It does not mean that the suite run has completed. To monitor progress of the run, check the Pulpito web interface URL periodically, or if you are impatient, ssh to the teuthology machine using the ssh command shown and do

tail -f /var/log/teuthology.*

The /usr/share/nginx/html directory contains the complete logs of the test suite. If we had provided the --upload option to the ceph-workbench ceph-qa-suite command, these logs would have been uploaded to http://teuthology-logs.public.ceph.com.

Run a standalone test

The standalone test explained in Reading a standalone test can be run with the following command

ceph-workbench ceph-qa-suite --suite rados/singleton/all/admin-socket.yaml

This will run the suite shown on the current master branch of ceph/ceph.git. You can specify a different branch with the --ceph option, and even a different git repo with the --ceph-git-url option. (Run ceph-workbench ceph-qa-suite --help for an up-to-date list of available options.)

The first run of a suite will also take a long time, because ceph packages have to be built, first. Again, the packages so built are cached and ceph-workbench ceph-qa-suite will not build identical packages a second time.

Interrupt a running suite

Teuthology suites take time to run. From time to time one may wish to interrupt a running suite. One obvious way to do this is:

.. prompt:: bash $

ceph-workbench ceph-qa-suite –teardown

This destroys all VMs created by ceph-workbench ceph-qa-suite and returns the OpenStack tenant to a “clean slate”.

Sometimes you may wish to interrupt the running suite, but keep the logs, the teuthology VM, the packages-repository VM, etc. To do this, you can ssh to the teuthology VM (using the ssh access command reported when you triggered the suite – see Run the dummy suite) and, once there

sudo /etc/init.d/teuthology restart

This will keep the teuthology machine, the logs and the packages-repository instance but nuke everything else.

Upload logs to archive server

Since the teuthology instance in OpenStack is only semi-permanent, with limited space for storing logs, teuthology-openstack provides an --upload option which, if included in the ceph-workbench ceph-qa-suite command, will cause logs from all failed jobs to be uploaded to the log archive server maintained by the Ceph project. The logs will appear at the URL:

http://teuthology-logs.public.ceph.com/$RUN

where $RUN is the name of the run. It will be a string like this:

ubuntu-2016-07-23_16:08:12-rados-hammer-backports---basic-openstack

Even if you don’t providing the --upload option, however, all the logs can still be found on the teuthology machine in the directory /usr/share/nginx/html.

Provision VMs ad hoc

From the teuthology VM, it is possible to provision machines on an “ad hoc” basis, to use however you like. The magic incantation is:

.. prompt:: bash $
teuthology-lock –lock-many $NUMBER_OF_MACHINES

–os-type $OPERATING_SYSTEM –os-version $OS_VERSION –machine-type openstack –owner $EMAIL_ADDRESS

The command must be issued from the ~/teuthology directory. The possible values for OPERATING_SYSTEM AND OS_VERSION can be found by examining the contents of the directory teuthology/openstack/. For example

teuthology-lock --lock-many 1 --os-type ubuntu --os-version 16.04 \
    --machine-type openstack --owner foo@example.com

When you are finished with the machine, find it in the list of machines

openstack server list

to determine the name or ID, and then terminate it with

openstack server delete $NAME_OR_ID

Deploy a cluster for manual testing

The teuthology framework and ceph-workbench ceph-qa-suite are versatile tools that automatically provision Ceph clusters in the cloud and run various tests on them in an automated fashion. This enables a single engineer, in a matter of hours, to perform thousands of tests that would keep dozens of human testers occupied for days or weeks if conducted manually.

However, there are times when the automated tests do not cover a particular scenario and manual testing is desired. It turns out that it is simple to adapt a test to stop and wait after the Ceph installation phase, and the engineer can then ssh into the running cluster. Simply add the following snippet in the desired place within the test YAML and schedule a run with the test:

tasks:
- exec:
    client.0:
      - sleep 1000000000 # forever

(Make sure you have a client.0 defined in your roles stanza or adapt accordingly.)

The same effect can be achieved using the interactive task:

tasks:
- interactive

By following the test log, you can determine when the test cluster has entered the “sleep forever” condition. At that point, you can ssh to the teuthology machine and from there to one of the target VMs (OpenStack) or teuthology worker machines machine (Sepia) where the test cluster is running.

The VMs (or “instances” in OpenStack terminology) created by ceph-workbench ceph-qa-suite are named as follows:

teuthology - the teuthology machine

packages-repository - VM where packages are stored

ceph-* - VM where packages are built

target* - machines where tests are run

The VMs named target* are used by tests. If you are monitoring the teuthology log for a given test, the hostnames of these target machines can be found out by searching for the string Locked targets:

2016-03-20T11:39:06.166 INFO:teuthology.task.internal:Locked targets:
  target149202171058.teuthology: null
  target149202171059.teuthology: null

The IP addresses of the target machines can be found by running openstack server list on the teuthology machine, but the target VM hostnames (e.g. target149202171058.teuthology) are resolvable within the teuthology cluster.