swift/doc/source/development_saio.rst

SAIO - Swift All In One

Instructions for setting up a development VM

This section documents setting up a virtual machine for doing Swift development. The virtual machine will emulate running a four node Swift cluster.

• Get an Ubuntu 12.04 LTS (Precise Pangolin) server image or try something Fedora/CentOS.
• Create guest virtual machine from the image.

Additional information about setting up a Swift development snapshot on other distributions is available on the wiki at http://wiki.openstack.org/SAIOInstructions.

What's in a <your-user-name>

Much of the configuration described in this guide requires escalated administrator (root) privileges; however, we assume that administrator logs in as an unprivileged user and can use sudo to run privileged commands.

Swift processes also run under a separate user and group, set by configuration option, and referenced as <your-user-name>:<your-group-name>. The default user is swift, which may not exist on your system. These instructions are intended to allow a developer to use his/her username for <your-user-name>:<your-group-name>.

Installing dependencies

• On apt based systems:

  sudo apt-get update
  sudo apt-get install curl gcc memcached rsync sqlite3 xfsprogs \
                       git-core libffi-dev python-setuptools
  sudo apt-get install python-coverage python-dev python-nose \
                       python-simplejson python-xattr python-eventlet \
                       python-greenlet python-pastedeploy \
                       python-netifaces python-pip python-dnspython \
                       python-mock

• On yum based systems:

  sudo yum update
  sudo yum install curl gcc memcached rsync sqlite xfsprogs git-core \
                   libffi-devel xinetd python-setuptools \
                   python-coverage python-devel python-nose \
                   python-simplejson pyxattr python-eventlet \
                   python-greenlet python-paste-deploy \
                   python-netifaces python-pip python-dns \
                   python-mock

  This installs necessary system dependencies; and most of the python dependencies. Later in the process setuptools/distribute or pip will install and/or upgrade some other stuff - it's getting harder to avoid. You can also install anything else you want, like screen, ssh, vim, etc.

Next, choose either partition-section or loopback-section.

Using a partition for storage

If you are going to use a separate partition for Swift data, be sure to add another device when creating the VM, and follow these instructions:

1. Set up a single partition:

   sudo fdisk /dev/sdb
   sudo mkfs.xfs /dev/sdb1

2. Edit /etc/fstab and add:

   /dev/sdb1 /mnt/sdb1 xfs noatime,nodiratime,nobarrier,logbufs=8 0 0

3. Create the mount point and the individualized links:

   sudo mkdir /mnt/sdb1
   sudo mount /mnt/sdb1
   sudo mkdir /mnt/sdb1/1 /mnt/sdb1/2 /mnt/sdb1/3 /mnt/sdb1/4
   sudo chown ${USER}:${USER} /mnt/sdb1/*
   sudo mkdir /srv
   for x in {1..4}; do sudo ln -s /mnt/sdb1/$x /srv/$x; done
   sudo mkdir -p /srv/1/node/sdb1 /srv/2/node/sdb2 /srv/3/node/sdb3 \
                 /srv/4/node/sdb4 /var/run/swift
   sudo chown -R ${USER}:${USER} /var/run/swift
   # **Make sure to include the trailing slash after /srv/$x/**
   for x in {1..4}; do sudo chown -R ${USER}:${USER} /srv/$x/; done

4. Next, skip to common-dev-section.

Using a loopback device for storage

If you want to use a loopback device instead of another partition, follow these instructions:

1. Create the file for the loopback device:

   sudo mkdir /srv
   sudo truncate -s 1GB /srv/swift-disk
   sudo mkfs.xfs /srv/swift-disk

   Modify size specified in the truncate command to make a larger or smaller partition as needed.

2. Edit /etc/fstab and add:

   /srv/swift-disk /mnt/sdb1 xfs loop,noatime,nodiratime,nobarrier,logbufs=8 0 0

3. Create the mount point and the individualized links:

   sudo mkdir /mnt/sdb1
   sudo mount /mnt/sdb1
   sudo mkdir /mnt/sdb1/1 /mnt/sdb1/2 /mnt/sdb1/3 /mnt/sdb1/4
   sudo chown ${USER}:${USER} /mnt/sdb1/*
   for x in {1..4}; do sudo ln -s /mnt/sdb1/$x /srv/$x; done
   sudo mkdir -p /srv/1/node/sdb1 /srv/2/node/sdb2 /srv/3/node/sdb3 /srv/4/node/sdb4 /var/run/swift
   sudo chown -R ${USER}:${USER} /var/run/swift
   # **Make sure to include the trailing slash after /srv/$x/**
   for x in {1..4}; do sudo chown -R ${USER}:${USER} /srv/$x/; done

Common Post-Device Setup

Add the following lines to /etc/rc.local (before the exit 0):

mkdir -p /var/cache/swift /var/cache/swift2 /var/cache/swift3 /var/cache/swift4
chown <your-user-name>:<your-group-name> /var/cache/swift*
mkdir -p /var/run/swift
chown <your-user-name>:<your-group-name> /var/run/swift

Note that on some systems you might have to create /etc/rc.local.

On Fedora 19 or later, you need to place these in /etc/rc.d/rc.local.

Getting the code

1. Check out the python-swiftclient repo:

   cd $HOME; git clone https://github.com/openstack/python-swiftclient.git

2. Build a development installation of python-swiftclient:

   cd $HOME/python-swiftclient; sudo python setup.py develop; cd -

3. Check out the swift repo:

   git clone https://github.com/openstack/swift.git

4. Build a development installation of swift:

   cd $HOME/swift; sudo python setup.py develop; cd -

   Fedora 19 or later users might have to perform the following if development installation of swift fails:

   sudo pip install -U xattr

5. Install swift's test dependencies:

   sudo pip install -r swift/test-requirements.txt

Setting up rsync

1. Create /etc/rsyncd.conf:

   sudo cp $HOME/swift/doc/saio/rsyncd.conf /etc/
   sudo sed -i "s/<your-user-name>/${USER}/" /etc/rsyncd.conf

   Here is the default rsyncd.conf file contents maintained in the repo that is copied and fixed up above:

   /../saio/rsyncd.conf

2. On Ubuntu, edit the following line in /etc/default/rsync:

   RSYNC_ENABLE=true

   On Fedora, edit the following line in /etc/xinetd.d/rsync:

   disable = no

   One might have to create the above files to perform the edits.

3. On platforms with SELinux in Enforcing mode, either set to Permissive:

   sudo setenforce Permissive

   Or just allow rsync full access:

   sudo setsebool -P rsync_full_access 1

4. Start the rsync daemon

   • On Ubuntu, run:

     sudo service rsync restart

   • On Fedora, run:

     sudo systemctl restart xinetd.service
     sudo systemctl enable rsyncd.service
     sudo systemctl start rsyncd.service

   • On other xinetd based systems simply run:

     sudo service xinetd restart

5. Verify rsync is accepting connections for all servers:

   rsync rsync://pub@localhost/

   You should see the following output from the above command:

   account6012
   account6022
   account6032
   account6042
   container6011
   container6021
   container6031
   container6041
   object6010
   object6020
   object6030
   object6040

Starting memcached

On non-Ubuntu distros you need to ensure memcached is running:

sudo service memcached start
sudo chkconfig memcached on

or:

sudo systemctl enable memcached.service
sudo systemctl start memcached.service

The tempauth middleware stores tokens in memcached. If memcached is not running, tokens cannot be validated, and accessing Swift becomes impossible.

Optional: Setting up rsyslog for individual logging

1. Install the swift rsyslogd configuration:

   sudo cp $HOME/swift/doc/saio/rsyslog.d/10-swift.conf /etc/rsyslog.d/

   Be sure to review that conf file to determine if you want all the logs in one file vs. all the logs separated out, and if you want hourly logs for stats processing. For convenience, we provide its default contents below:

   /../saio/rsyslog.d/10-swift.conf

2. Edit /etc/rsyslog.conf and make the following change (usually in the "GLOBAL DIRECTIVES" section):

   $PrivDropToGroup adm

3. If using hourly logs (see above) perform:

   sudo mkdir -p /var/log/swift/hourly

   Otherwise perform:

   sudo mkdir -p /var/log/swift

4. Setup the logging directory and start syslog:

   • On Ubuntu:

     sudo chown -R syslog.adm /var/log/swift
     sudo chmod -R g+w /var/log/swift
     sudo service rsyslog restart

   • On Fedora:

     sudo chown -R root:adm /var/log/swift
     sudo chmod -R g+w /var/log/swift
     sudo systemctl restart rsyslog.service

Configuring each node

After performing the following steps, be sure to verify that Swift has access to resulting configuration files (sample configuration files are provided with all defaults in line-by-line comments).

1. Optionally remove an existing swift directory:

   sudo rm -rf /etc/swift

2. Populate the /etc/swift directory itself:

   cd $HOME/swift/doc; sudo cp -r saio/swift /etc/swift; cd -
   sudo chown -R ${USER}:${USER} /etc/swift

3. Update <your-user-name> references in the Swift config files:

   find /etc/swift/ -name \*.conf | xargs sudo sed -i "s/<your-user-name>/${USER}/"

The contents of the configuration files provided by executing the above commands are as follows:

1. /etc/swift/swift.conf

   /../saio/swift/swift.conf

2. /etc/swift/proxy-server.conf

   /../saio/swift/proxy-server.conf

3. /etc/swift/object-expirer.conf

   /../saio/swift/object-expirer.conf

4. /etc/swift/account-server/1.conf

   /../saio/swift/account-server/1.conf

5. /etc/swift/container-server/1.conf

   /../saio/swift/container-server/1.conf

6. /etc/swift/object-server/1.conf

   /../saio/swift/object-server/1.conf

7. /etc/swift/account-server/2.conf

   /../saio/swift/account-server/2.conf

8. /etc/swift/container-server/2.conf

   /../saio/swift/container-server/2.conf

9. /etc/swift/object-server/2.conf

   /../saio/swift/object-server/2.conf

10. /etc/swift/account-server/3.conf

    /../saio/swift/account-server/3.conf

11. /etc/swift/container-server/3.conf

    /../saio/swift/container-server/3.conf

12. /etc/swift/object-server/3.conf

    /../saio/swift/object-server/3.conf

13. /etc/swift/account-server/4.conf

    /../saio/swift/account-server/4.conf

14. /etc/swift/container-server/4.conf

    /../saio/swift/container-server/4.conf

15. /etc/swift/object-server/4.conf

    /../saio/swift/object-server/4.conf

Setting up scripts for running Swift

1. Copy the SAIO scripts resetting the environment:

   cd $HOME/swift/doc; cp -r saio/bin $HOME/bin; cd -
   chmod +x $HOME/bin/*

2. Edit the $HOME/bin/resetswift script

   If you are using a loopback device substitute /dev/sdb1 with /srv/swift-disk in the mkfs step:

   sed -i "s/dev\/sdb1/srv\/swift-disk/" $HOME/bin/resetswift

   If you did not set up rsyslog for individual logging, remove the find /var/log/swift... line:

   sed -i "/find \/var\/log\/swift/d" $HOME/bin/resetswift

   On Fedora, replace service <name> restart with systemctl restart <name>.service:

   sed -i "s/service \(.*\) restart/systemctl restart \1.service/" $HOME/bin/resetswift

   The template resetswift script looks like the following:

   /../saio/bin/resetswift

3. Install the sample configuration file for running tests:

   cp $HOME/swift/test/sample.conf /etc/swift/test.conf

   The template test.conf looks like the following:

   /../../test/sample.conf

4. Add an environment variable for running tests below:

   echo "export SWIFT_TEST_CONFIG_FILE=/etc/swift/test.conf" >> $HOME/.bashrc

5. Be sure that your PATH includes the bin directory:

   echo "export PATH=${PATH}:$HOME/bin" >> $HOME/.bashrc

6. Source the above environment variables into your current environment:

   . $HOME/.bashrc

7. Construct the initial rings using the provided script:

   remakerings

   The remakerings script looks like the following:

   /../saio/bin/remakerings

   You can expect the ouptut from this command to produce the following:

   Device d0r1z1-127.0.0.1:6010R127.0.0.1:6010/sdb1_"" with 1.0 weight got id 0
   Device d1r1z2-127.0.0.1:6020R127.0.0.1:6020/sdb2_"" with 1.0 weight got id 1
   Device d2r1z3-127.0.0.1:6030R127.0.0.1:6030/sdb3_"" with 1.0 weight got id 2
   Device d3r1z4-127.0.0.1:6040R127.0.0.1:6040/sdb4_"" with 1.0 weight got id 3
   Reassigned 1024 (100.00%) partitions. Balance is now 0.00.
   Device d0r1z1-127.0.0.1:6011R127.0.0.1:6011/sdb1_"" with 1.0 weight got id 0
   Device d1r1z2-127.0.0.1:6021R127.0.0.1:6021/sdb2_"" with 1.0 weight got id 1
   Device d2r1z3-127.0.0.1:6031R127.0.0.1:6031/sdb3_"" with 1.0 weight got id 2
   Device d3r1z4-127.0.0.1:6041R127.0.0.1:6041/sdb4_"" with 1.0 weight got id 3
   Reassigned 1024 (100.00%) partitions. Balance is now 0.00.
   Device d0r1z1-127.0.0.1:6012R127.0.0.1:6012/sdb1_"" with 1.0 weight got id 0
   Device d1r1z2-127.0.0.1:6022R127.0.0.1:6022/sdb2_"" with 1.0 weight got id 1
   Device d2r1z3-127.0.0.1:6032R127.0.0.1:6032/sdb3_"" with 1.0 weight got id 2
   Device d3r1z4-127.0.0.1:6042R127.0.0.1:6042/sdb4_"" with 1.0 weight got id 3
   Reassigned 1024 (100.00%) partitions. Balance is now 0.00.

8. Verify the unit tests run:

   $HOME/swift/.unittests

   Note that the unit tests do not require any swift daemons running.

9. Start the "main" Swift daemon processes (proxy, account, container, and object):

   startmain

   (The "Unable to increase file descriptor limit. Running as non-root?" warnings are expected and ok.)

   The startmain script looks like the following:

   /../saio/bin/startmain

10. Get an X-Storage-Url and X-Auth-Token:

    curl -v -H 'X-Storage-User: test:tester' -H 'X-Storage-Pass: testing' http://127.0.0.1:8080/auth/v1.0

11. Check that you can GET account:

    curl -v -H 'X-Auth-Token: <token-from-x-auth-token-above>' <url-from-x-storage-url-above>

12. Check that swift command provided by the python-swiftclient package works:

    swift -A http://127.0.0.1:8080/auth/v1.0 -U test:tester -K testing stat

13. Verify the functional tests run:

    $HOME/swift/.functests

    (Note: functional tests will first delete everything in the configured accounts.)

14. Verify the probe tests run:

    $HOME/swift/.probetests

    (Note: probe tests will reset your environment as they call resetswift for each test.)

Debugging Issues

If all doesn't go as planned, and tests fail, or you can't auth, or something doesn't work, here are some good starting places to look for issues:

1. Everything is logged using system facilities -- usually in /var/log/syslog, but possibly in /var/log/messages on e.g. Fedora -- so that is a good first place to look for errors (most likely python tracebacks).
2. Make sure all of the server processes are running. For the base functionality, the Proxy, Account, Container, and Object servers should be running.
3. If one of the servers are not running, and no errors are logged to syslog, it may be useful to try to start the server manually, for example: swift-object-server /etc/swift/object-server/1.conf will start the object server. If there are problems not showing up in syslog, then you will likely see the traceback on startup.
4. If you need to, you can turn off syslog for unit tests. This can be useful for environments where /dev/log is unavailable, or which cannot rate limit (unit tests generate a lot of logs very quickly). Open the file SWIFT_TEST_CONFIG_FILE points to, and change the value of fake_syslog to True.