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NAME
    ec2-consistent-snapshot - Create EBS snapshots on EC2 w/consistent
    filesystem/db

SYNOPSIS
     ec2-consistent-snapshot [opts] VOLUMEID...

OPTIONS
    -h --help
        Print help and exit.

    -d --debug
        Debug mode.

    -q --quiet
        Quiet mode.

    -n --noaction
        Don't do it. Just say what you would have done.

    --aws-access-key-id KEY
    --aws-secret-access-key SECRET
        Amazon AWS access key and secret access key. Defaults to environment
        variables or .awssecret file contents described below.

    --aws-access-key-id-file KEYFILE
    --aws-secret-access-key-file SECRETFILE
        Files containing Amazon AWS access key and secret access key.
        Defaults to environment variables or .awssecret file contents
        described below.

    --aws-credentials-file CREDENTIALSFILE
        File containing both the Amazon AWS access key and secret access key
        on seprate lines and in that order. Defaults to contents of
        $AWS_CREDENTIALS environment variable or the value $HOME/.awssecret

    --region REGION
        Specify a different EC2 region like "eu-west-1". Defaults to
        "us-east-1".

    --description DESCRIPTION
        Specify a description string for the EBS snapshot. Defaults to the
        name of the program.

        You may specify this option multiple times if you need to customize
        descriptions of multiple volumes snapshots. If specified multiple
        times descriptions count has to match volumes count and they will be
        applied on the same order.

    --freeze-filesystem MOUNTPOINT
    --xfs-filesystem MOUNTPOINT [OBSOLESCENT form of the same option]
        Indicates that the filesystem at the specified mount point should be
        flushed and frozen during the snapshot. Requires the xfs_freeze or
        fsfreeze program. Note that xfs_freeze is equivalent to fsfreeze and
        works on any filesystems that support freezing, provided the kernel
        you are using supports it. (Linux Ext3/4, ReiserFS, JFS, XFS.)
        fsfreeze comes with newer versions of util-linux.

        You may specify this option multiple times if you need to freeze
        multiple filesystems on the the EBS volume(s).

    --mongo
        Indicates that the volume contains data files for a running Mongo
        database, which will be flushed and locked during the snapshot.

    --mongo-host HOST
    --mongo-port PORT
    --mongo-username USER
    --mongo-password PASS
        Mongo host, port, username, and password used to flush logs if there
        is authentication required on the admin database.

    --mongo-stop
        Indicates that the volume contains data files for a running Mongo
        instance.  The instance is shutdown before the snapshot is initiated
        and restarted afterwards. [EXPERIMENTAL]

    --mysql
        Indicates that the volume contains data files for a running MySQL
        database, which will be flushed and locked during the snapshot.

    --mysql-defaults-file FILE
        MySQL defaults file, containing host, username and password, this
        option will ignore the --mysql-host, --mysql-username,
        --mysql-password parameters

    --mysql-host HOST
    --mysql-socket PATH
    --mysql-username USER
    --mysql-password PASS
        MySQL host, socket path, username, and password used to flush logs
        and lock tables. User must have appropriate permissions. Defaults to
        $HOME/.my.cnf file contents.

    --mysql-master-status-file FILE
        Store the MASTER STATUS output in a file on the snapshot. It will be
        removed after the EBS snapshot is taken. This option will be ignored
        with --mysql-stop

    --mysql-stop
        Indicates that the volume contains data files for a running MySQL
        database. The database is shutdown before the snapshot is initiated
        and restarted afterwards. [EXPERIMENTAL]

    --snapshot-timeout SECONDS
        How many seconds to wait for the snapshot-create to return. Defaults
        to 10.0

    --lock-timeout SECONDS
        How many seconds to wait for a database lock. Defaults to 0.5.
        Making this too large can force other processes to wait while this
        process waits for a lock. Better to make it small and try lots of
        times.

    --lock-tries COUNT
        How many times to try to get a database lock before failing.
        Defaults to 60.

    --lock-sleep SECONDS
        How many seconds to sleep between database lock tries. Defaults to
        5.0.

    --pre-freeze-command COMMAND
        Command to run after MySQL stop/lock and before filesystem freeze.

    --post-thaw-command COMMAND
        Command to run immediately after filesystem unfreeze and before
        MySQL start/unlock.

ARGUMENTS
    VOLUMEID
        EBS volume id(s) for which a snapshot is to be created.

DESCRIPTION
    This program creates an EBS snapshot for an Amazon EC2 EBS volume. To
    help ensure consistent data in the snapshot, it tries to flush and
    freeze the filesystem(s) first as well as flushing and locking the
    database, if applicable.

    Filesystems can be frozen during the snapshot. Prior to Linux kernel
    2.6.29, XFS must be used for freezing support. While frozen, a
    filesystem will be consistent on disk and all writes will block.

    There are a number of timeouts to reduce the risk of interfering with
    the normal database operation while improving the chances of getting a
    consistent snapshot.

    If you have multiple EBS volumes in a RAID configuration, you can
    specify all of the volume ids on the command line and it will create
    snapshots for each while the filesystem and database are locked. Note
    that it is your responsibility to keep track of the resulting snapshot
    ids and to figure out how to put these back together when you need to
    restore the RAID setup.

    If you have multiple EBS volumes which are hosting different file
    systems, it might be better to simply run the command once for each
    volume id.

EXAMPLES
    Snapshot a volume with a frozen filesystem under /vol containing a MySQL
    database:

     ec2-consistent-snapshot --mysql --freeze-filesystem /vol vol-VOLUMEID

    Snapshot a volume mounted with a frozen filesystem on /var/local but
    with no MySQL database:

     ec2-consistent-snapshot --freeze-filesystem /var/local vol-VOLUMEID

    Snapshot four European volumes in a RAID configuration with MySQL,
    saving the snapshots with a description marking the current time:

     ec2-consistent-snapshot                                      \
       --mysql                                                    \
       --freeze-filesystem /vol                                   \
       --region eu-west-1                                         \
       --description "RAID snapshot $(date +'%Y-%m-%d %H:%M:%S')" \
       vol-VOL1 vol-VOL2 vol-VOL3 vol-VOL4

    Snapshot two volumes with customized descriptions:

     ec2-consistent-snapshot                                      \
       --description "Description 1st Volume"                     \
       --description "Description 2nd Volume"                     \
       vol-VOL1 vol-VOL2

ENVIRONMENT
    $AWS_ACCESS_KEY_ID
        Default value for access key. Can be overridden by command line
        options.

    $AWS_SECRET_ACCESS_KEY
        Default value for secret access key. Can be overridden by command
        line options.

    $AWS_CREDENTIALS
        Default value for filename containing both access key and secret
        access key on separate lines and in that order. Can be overriden by
        the --aws-credentials command line option.

FILES
    $HOME/.my.cnf
        Default values for MySQL user and password are sought here in the
        standard format.

    $HOME/.awssecret
        Default values for access key and secret access keys are sought
        here. Can be overridden by environment variables and command line
        options.

INSTALLATION
    On most Ubuntu releases, the ec2-consistent-snapshot package can be
    installed directly from the Alestic.com PPA using the following
    commands:

     sudo add-apt-repository ppa:alestic
     sudo apt-get update
     sudo apt-get install ec2-consistent-snapshot

    This program may also require the installation of the Net::Amazon::EC2,
    MongoDB::Admin, and Any::Moose Perl packages from CPAN. On Ubuntu 10.04
    Lucid and higher, this should happen automatically by the dependency on
    the libnet-amazon-ec2-perl package.

    On some earlier releases of Ubuntu you can install the required packages
    with the following commands:

     sudo PERL_MM_USE_DEFAULT=1 cpan Net::Amazon::EC2
     sudo PERL_MM_USE_DEFAULT=1 cpan -fi MongoDB MongoDB::Admin
     sudo PERL_MM_USE_DEFAULT=1 cpan -fi Any Any::Moose

    On Ubuntu 8.04 Hardy, use the following commands instead:

     code=$(lsb_release -cs)
     echo "deb http://ppa.launchpad.net/alestic/ppa/ubuntu $code main"|
       sudo tee /etc/apt/sources.list.d/alestic-ppa.list
     sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys BE09C571
     sudo apt-get update
     sudo apt-get install ec2-consistent-snapshot build-essential
     sudo cpan Net::Amazon::EC2
     sudo cpan MongoDB::Admin
     sudo cpan Any::Moose

    The default values can be accepted for most of the prompts, though it is
    necessary to select a CPAN mirror on Hardy.

SEE ALSO
    Amazon EC2
    Amazon EC2 EBS (Elastic Block Store)
    ec2-create-snapshot

CAVEATS
    This program currently supports the MySQL and MongoDB databases. Patches
    are welcomed for other databases.

    EBS snapshots are a critical part of protecting your valuable data. This
    program or the environment in which it is run may contain defects that
    cause snapshots to not be created. Please test and check to make sure
    that snapshots are getting created for the volumes as you intend.

    EBS snapshots cost money to create and to store in your AWS account. Be
    aware of and monitor your expenses.

    You are responsible for what happens in your EC2 account. This software
    is intended, but not guaranteed, to help in that effort.

    This program tries hard to figure out some values are for the AWS key
    and AWS secret access key. In fact, it tries too hard. This results in
    possibly using some credentials it finds that are not the correct ones
    you wish to use, especially if you are operating in an environment where
    multiple sets of credentials are in use.

BUGS
    Please report bugs at https://bugs.launchpad.net/ec2-consistent-snapshot

CREDITS
    Thanks to the following for performing tests on early versions,
    providing feedback, and patches:

      David Erickson
      Steve Caldwell
      Gryp
      Ken Huang
      Jefferson Noxon
      Bobb Crosbie
      Craig Tracey
      Diego Salvi
      Christian Marquardt
      Todd Roman
      Eric Lubow
      Kevin Lewis

AUTHOR
    Eric Hammond <ehammond@thinksome.com>

LICENSE
    Copyright 2009-2012 Eric Hammond <ehammond@thinksome.com>

    Licensed under the Apache License, Version 2.0 (the "License"); you may
    not use this file except in compliance with the License. You may obtain
    a copy of the License at

     http://www.apache.org/licenses/LICENSE-2.0

    Unless required by applicable law or agreed to in writing, software
    distributed under the License is distributed on an "AS IS" BASIS,
    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    See the License for the specific language governing permissions and
    limitations under the License.

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