Bareos Tape Backup on a 124T

I use Bareos (a fork of Bacula) to backup my data at home from a Linux computer to tape. Backing up to tape is a lot more convenient that backing up to DVD-R/BD-R, though it’s probably debatable when compared to backing up to an external hard drive. But having a tape autoloader is so cool!

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Equipment Used

This guide should work with other pieces of equipment but it has been written with these devices in mind:

The plan is to rsync data from my OS X client to a directory on my Linux server, and to run all Bareos software on just the server. I didn’t like the idea of having some process running as root on OS X and trust that it only accessed a specific volume, which isn’t even configured on OS X (it’s set in the Bareos director config on the Linux server).

I’ll be running backups manually. I won’t have any running schedules in Bareos and I’ll have MariaDB (MySQL on CentOS) and Bareos not start on boot. After every backup I’ll stop those services.

I’ll also only be defining full backups. I won’t be defining any differential/incremental jobs in this guide.

Installation

We’ll be installing Bareos and its dependencies from scratch on a new CentOS install. Some things I’d like to point out:

  1. The giant bareos-dir.conf will be split up into 3 files for easier manageability.
  2. I won’t be using any kind of monitoring, emailing, or any sort of notifications. I’ll just manually check the progress through the bconsole. Since my CentOS server doesn’t run a GUI I don’t have a tray-monitor.

Verify Tape Drive/Autoloader

First we need to make sure the tape drive and autoloader have been detected by the OS. Do this by running lsscsi -g (don’t need to be root). You should see something like this:

$ lsscsi -g
[0:0:6:0]    tape    IBM      ULTRIUM-TD3      93GM  /dev/st0   /dev/sg2
[0:0:6:1]    mediumx DELL     PV-124T          0085  /dev/sch0  /dev/sg3

If you don’t see any sg devices you can try these commands, I had to run them on my CentOS installation:

sudo su -c 'echo "sg" > /etc/modules-load.d/sg.conf'
sudo systemctl restart systemd-modules-load.service

Install Bareos

We’ll be using MariaDB as the backend database. Install it and secure it.

sudo yum install mariadb-server
sudo systemctl start mariadb.service
sudo systemctl disable mariadb.service
mysql_secure_installation  # Ignore find_mysql_client error.

Next install Bareos.

wget "http://download.bareos.org/bareos/release/latest/CentOS_7/bareos.repo"
sudo cp bareos.repo /etc/yum.repos.d/
sudo yum install bareos bareos-database-mysql bareos-storage-tape
sudo systemctl disable bareos-dir.service
sudo systemctl disable bareos-sd.service
sudo systemctl disable bareos-fd.service
sudo /usr/lib/bareos/scripts/create_bareos_database mysql -u root -p
sudo /usr/lib/bareos/scripts/make_bareos_tables mysql -u root -p
dbpw=$(openssl rand -base64 45)
sudo db_password="$dbpw" /usr/lib/bareos/scripts/grant_bareos_privileges mysql -u root -p
sudo sed -i.bak '[email protected]\(dbpassword =\) ""@\1 "'$dbpw'"@g' /etc/bareos/bareos-dir.conf
unset dbpw

I’ll be using /home/bareos to rsync files to. I’ll need to grant the bareos user access to this so it may backup and restore files there, and I’ll also need to grant another user (e.g. support) access to login through rsync (it’s a bad idea to grant login privileges to bareos).

sudo mkdir -m0700 /home/bareos
sudo chown bareos:bareos /home/bareos
sudo setfacl -d -m u:bareos:rwx -m g:support:rwx /home/bareos
sudo setfacl -m u:bareos:rwx -m g:support:rwx /home/bareos

File/Storage Daemon Config

Overwrite these two files. Make sure to substitute moops with the original setting. Omit the PKI lines if you do not plan on encrypting your backup file data.

Warning

While Bareos does support encryption, bscan and bextract do not! This means if you ever lose your Bareos server and you do not have a clear-text backup of your MySQL database, you won’t be able to restore the catalog from tape (even if you have your encryption keys) without a lot of manual and unsupported work.

# /etc/bareos/bareos-fd.conf
Director {
  Name = moops-dir
  Password = "PUT_ORIGINAL_VALUE_HERE"
}

FileDaemon {
  Name = moops-fd
  Maximum Concurrent Jobs = 20
  PKI Signatures = Yes  # Enable Data Signing
  PKI Encryption = Yes  # Enable Data Encryption
  PKI Keypair = /etc/bareos/moops-fd.pem  # Public and Private Keys
  PKI Master Key = /etc/bareos/master.cert  # ONLY the Public Key
}

Messages {
  Name = Standard
  director = moops-dir = all, !skipped, !restored
}

For the storage daemon substitute /dev/sg3 and /dev/nst0 below with the device files found on your system. We’ll be verifying them in the next section.

# /etc/bareos/bareos-sd.conf
Storage {
  Name = moops-sd
  Maximum Concurrent Jobs = 20
}

Director {
  Name = moops-dir
  Password = "PUT_ORIGINAL_VALUE_HERE"
}

Autochanger {
  Name = PV-124T
  Device = ULTRIUM-TD3
  Changer Device = /dev/sg3
  Changer Command = "/usr/lib/bareos/scripts/mtx-changer %c %o %S %a %d"
}

Device {
  Name = ULTRIUM-TD3
  Media Type = LTO-3
  Archive Device = /dev/nst0
  Autochanger = yes
  AutomaticMount = yes
  AlwaysOpen = yes
}

Device {
  Name = FileStorage
  Media Type = File
  Archive Device = /home/bareos/tmp
  LabelMedia = yes;
  Random Access = Yes;
  AutomaticMount = yes;
  RemovableMedia = no;
  AlwaysOpen = no;
}

Messages {
  Name = Standard
  director = moops-dir = all
}

Verify Storage Config

Before we go any further we should make sure the storage daemon configuration file is valid. We can easily test this with the commands below. Load up a tape inside the tape drive and another tape in slot 1 in your autoloader. I did this using my autoloader’s web interface.

First we make sure the tape drive works. Substitute /dev/nst0 with what you have in the storage daemon config:

sudo mt -f /dev/nst0 rewind
mkdir src dst && date > ./src/date.txt
sudo tar -cvf /dev/nst0 src
sudo mt -f /dev/nst0 rewind
sudo tar -xvf /dev/nst0 -C dst
ls -lah src/ dst/src/; cat src/date.txt dst/src/date.txt

Next we’ll test the autoloader as well as the storage daemon config:

sudo mtx -f /dev/sg3 inquiry  # Test autoloader.
sudo btape /dev/nst0  # Run "test" in the console.

This is what I got when I ran those two commands:

$ sudo mtx -f /dev/sg3 inquiry
Product Type: Medium Changer
Vendor ID: 'DELL    '
Product ID: 'PV-124T         '
Revision: '0085'
Attached Changer API: No
$ sudo btape /dev/nst0
Tape block granularity is 1024 bytes.
btape: butil.c:301-0 Using device: "/dev/nst0" for writing.
btape: btape.c:484-0 open device "ULTRIUM-TD3" (/dev/nst0): OK
*test

=== Write, rewind, and re-read test ===

I'm going to write 10000 records and an EOF
then write 10000 records and an EOF, then rewind,
and re-read the data to verify that it is correct.

This is an *essential* feature ...

btape: btape.c:1171-0 Wrote 10000 blocks of 64412 bytes.
btape: btape.c:616-0 Wrote 1 EOF to "ULTRIUM-TD3" (/dev/nst0)
btape: btape.c:1187-0 Wrote 10000 blocks of 64412 bytes.
btape: btape.c:616-0 Wrote 1 EOF to "ULTRIUM-TD3" (/dev/nst0)
btape: btape.c:1229-0 Rewind OK.
10000 blocks re-read correctly.
Got EOF on tape.
10000 blocks re-read correctly.
=== Test Succeeded. End Write, rewind, and re-read test ===

btape: btape.c:1297-0 Block position test
btape: btape.c:1309-0 Rewind OK.
Reposition to file:block 0:4
Block 5 re-read correctly.
Reposition to file:block 0:200
Block 201 re-read correctly.
Reposition to file:block 0:9999
Block 10000 re-read correctly.
Reposition to file:block 1:0
Block 10001 re-read correctly.
Reposition to file:block 1:600
Block 10601 re-read correctly.
Reposition to file:block 1:9999
Block 20000 re-read correctly.
=== Test Succeeded. End Write, rewind, and re-read test ===



=== Append files test ===

This test is essential to Bareos.

I'm going to write one record  in file 0,
                   two records in file 1,
             and three records in file 2

btape: btape.c:586-0 Rewound "ULTRIUM-TD3" (/dev/nst0)
btape: btape.c:1928-0 Wrote one record of 64412 bytes.
btape: btape.c:1930-0 Wrote block to device.
btape: btape.c:616-0 Wrote 1 EOF to "ULTRIUM-TD3" (/dev/nst0)
btape: btape.c:1928-0 Wrote one record of 64412 bytes.
btape: btape.c:1930-0 Wrote block to device.
btape: btape.c:1928-0 Wrote one record of 64412 bytes.
btape: btape.c:1930-0 Wrote block to device.
btape: btape.c:616-0 Wrote 1 EOF to "ULTRIUM-TD3" (/dev/nst0)
btape: btape.c:1928-0 Wrote one record of 64412 bytes.
btape: btape.c:1930-0 Wrote block to device.
btape: btape.c:1928-0 Wrote one record of 64412 bytes.
btape: btape.c:1930-0 Wrote block to device.
btape: btape.c:1928-0 Wrote one record of 64412 bytes.
btape: btape.c:1930-0 Wrote block to device.
btape: btape.c:616-0 Wrote 1 EOF to "ULTRIUM-TD3" (/dev/nst0)
btape: btape.c:484-0 open device "ULTRIUM-TD3" (/dev/nst0): OK
btape: btape.c:586-0 Rewound "ULTRIUM-TD3" (/dev/nst0)
btape: btape.c:1441-0 Now moving to end of medium.
btape: btape.c:637-0 Moved to end of medium.
We should be in file 3. I am at file 3. This is correct!

Now the important part, I am going to attempt to append to the tape.

btape: btape.c:1928-0 Wrote one record of 64412 bytes.
btape: btape.c:1930-0 Wrote block to device.
btape: btape.c:616-0 Wrote 1 EOF to "ULTRIUM-TD3" (/dev/nst0)
btape: btape.c:586-0 Rewound "ULTRIUM-TD3" (/dev/nst0)
Done appending, there should be no I/O errors

Doing Bareos scan of blocks:
1 block of 64448 bytes in file 1
End of File mark.
2 blocks of 64448 bytes in file 2
End of File mark.
3 blocks of 64448 bytes in file 3
End of File mark.
1 block of 64448 bytes in file 4
End of File mark.
Total files=4, blocks=7, bytes = 451,136
End scanning the tape.
We should be in file 4. I am at file 4. This is correct!

The above Bareos scan should have output identical to what follows.
Please double check it ...
=== Sample correct output ===
1 block of 64448 bytes in file 1
End of File mark.
2 blocks of 64448 bytes in file 2
End of File mark.
3 blocks of 64448 bytes in file 3
End of File mark.
1 block of 64448 bytes in file 4
End of File mark.
Total files=4, blocks=7, bytes = 451,136
=== End sample correct output ===

If the above scan output is not identical to the
sample output, you MUST correct the problem
or Bareos will not be able to write multiple Jobs to
the tape.


=== Write, backup, and re-read test ===

I'm going to write three records and an EOF
then backup over the EOF and re-read the last record.
Bareos does this after writing the last block on the
tape to verify that the block was written correctly.

This is not an *essential* feature ...

btape: btape.c:586-0 Rewound "ULTRIUM-TD3" (/dev/nst0)
btape: btape.c:823-0 Wrote first record of 64412 bytes.
btape: btape.c:834-0 Wrote second record of 64412 bytes.
btape: btape.c:845-0 Wrote third record of 64412 bytes.
btape: btape.c:616-0 Wrote 1 EOF to "ULTRIUM-TD3" (/dev/nst0)
btape: btape.c:861-0 Backspaced over EOF OK.
btape: btape.c:866-0 Backspace record OK.
btape: btape.c:884-0
Block re-read correct. Test succeeded!
=== End Write, backup, and re-read test ===



=== Forward space files test ===

This test is essential to Bareos.

I'm going to write five files then test forward spacing

btape: btape.c:586-0 Rewound "ULTRIUM-TD3" (/dev/nst0)
btape: btape.c:1928-0 Wrote one record of 64412 bytes.
btape: btape.c:1930-0 Wrote block to device.
btape: btape.c:616-0 Wrote 1 EOF to "ULTRIUM-TD3" (/dev/nst0)
btape: btape.c:1928-0 Wrote one record of 64412 bytes.
btape: btape.c:1930-0 Wrote block to device.
btape: btape.c:1928-0 Wrote one record of 64412 bytes.
btape: btape.c:1930-0 Wrote block to device.
btape: btape.c:616-0 Wrote 1 EOF to "ULTRIUM-TD3" (/dev/nst0)
btape: btape.c:1928-0 Wrote one record of 64412 bytes.
btape: btape.c:1930-0 Wrote block to device.
btape: btape.c:1928-0 Wrote one record of 64412 bytes.
btape: btape.c:1930-0 Wrote block to device.
btape: btape.c:1928-0 Wrote one record of 64412 bytes.
btape: btape.c:1930-0 Wrote block to device.
btape: btape.c:616-0 Wrote 1 EOF to "ULTRIUM-TD3" (/dev/nst0)
btape: btape.c:1928-0 Wrote one record of 64412 bytes.
btape: btape.c:1930-0 Wrote block to device.
btape: btape.c:1928-0 Wrote one record of 64412 bytes.
btape: btape.c:1930-0 Wrote block to device.
btape: btape.c:616-0 Wrote 1 EOF to "ULTRIUM-TD3" (/dev/nst0)
btape: btape.c:1928-0 Wrote one record of 64412 bytes.
btape: btape.c:1930-0 Wrote block to device.
btape: btape.c:616-0 Wrote 1 EOF to "ULTRIUM-TD3" (/dev/nst0)
btape: btape.c:586-0 Rewound "ULTRIUM-TD3" (/dev/nst0)
btape: btape.c:1655-0 Now forward spacing 1 file.
We should be in file 1. I am at file 1. This is correct!
btape: btape.c:1667-0 Now forward spacing 2 files.
We should be in file 3. I am at file 3. This is correct!
btape: btape.c:586-0 Rewound "ULTRIUM-TD3" (/dev/nst0)
btape: btape.c:1680-0 Now forward spacing 4 files.
We should be in file 4. I am at file 4. This is correct!

btape: btape.c:1698-0 Now forward spacing 1 more file.
We should be in file 5. I am at file 5. This is correct!

=== End Forward space files test ===


Ah, I see you have an autochanger configured.
To test the autochanger you must have a blank tape
 that I can write on in Slot 1.

Do you wish to continue with the Autochanger test? (y/n): y


=== Autochanger test ===

3301 Issuing autochanger "loaded" command.
Slot 1 loaded. I am going to unload it.
3302 Issuing autochanger "unload 1 0" command.
unload status=OK 0
3303 Issuing autochanger "load 1 0" command.
3303 Autochanger "load 1 0" status is OK.
btape: btape.c:484-0 open device "ULTRIUM-TD3" (/dev/nst0): OK
btape: btape.c:1585-0 Rewound "ULTRIUM-TD3" (/dev/nst0)
btape: btape.c:1592-0 Wrote EOF to "ULTRIUM-TD3" (/dev/nst0)

The test autochanger worked!!

*q

Director Daemon Config

Finally we configure the Bareos director. I’ll be defining three separate directories to backup. You may substitute this for one directory or however many you need. These directories will be owned by bareos:bareos and will be populated remotely using rsync (e.g. pushed from my OS X desktop computer).

Note

The Bareos documentation encourages you not to use localhost in your configuration. Instead use the FQDN and make sure you can resolve it properly.

We’ll be splitting up the director configuration into a few files since otherwise it would be pretty big. If you don’t like that you can just merge these into bareos-dir.conf and it’ll work just the same.

# /etc/bareos/bareos-dir.d/filesets.conf  # chown bareos:bareos; chmod 0640

# Optional for testing the config.
FileSet {
  Name = SelfTest
  Include {
    Options {
      CheckFileChanges = yes
      NoATime = yes
      Signature = SHA1
      Verify = 1
    }
    File = /home/bareos/selftest
  }
}

# Required for the Bareos catalog backup.
FileSet {
  Name = Catalog
  Include {
    Options {
      signature = SHA1
    }
    File = /var/lib/bareos/bareos.sql
    File = /etc/bareos
  }
}

# Where I store my files.
FileSet {
  Name = BoscoMain
  Include {
    Options {
      CheckFileChanges = yes
      NoATime = yes
      Signature = SHA1
      Verify = 1
    }
    File = /home/bareos/bosco/Main
  }
}

# Other files to backup.
FileSet {
  Name = BoscoOld
  Include {
    Options {
      CheckFileChanges = yes
      NoATime = yes
      Signature = SHA1
      Verify = 1
    }
    File = /home/bareos/bosco/Old
  }
}
# /etc/bareos/bareos-dir.d/jobs.conf  # chown bareos:bareos; chmod 0640

# Default settings for a job.
JobDefs {
  Name = DefaultJob
  Type = Backup
  Level = Full
  Client = moops-fd
  Storage = Tape
  Messages = Standard
  Pool = Full
  Write Bootstrap = /var/lib/bareos/%c.bsr
}

Job {
  Name = BackupSelfTest
  FileSet = SelfTest
  JobDefs = DefaultJob
}

Job {
  Name = BackupCatalog
  FileSet = Catalog
  JobDefs = DefaultJob
  RunBeforeJob = "/usr/lib/bareos/scripts/make_catalog_backup.pl Catalog"
  # RunAfterJob  = /usr/lib/bareos/scripts/delete_catalog_backup
  Priority = 11
}

Job {
  Name = BackupBoscoMain
  FileSet = BoscoMain
  JobDefs = DefaultJob
  Priority = 8
}

Job {
  Name = BackupBoscoOld
  FileSet = BoscoOld
  JobDefs = DefaultJob
  Priority = 10
}

# Only one restore job is needed for all Jobs/Clients/Storage.
Job {
  Name = RestoreFiles
  Type = Restore
  Client = moops-fd
  FileSet = BoscoMain
  Storage = File
  Pool = Full
  Messages = Standard
  Where = /home/bareos/tmp/restores
}
# /etc/bareos/bareos-dir.conf
@/etc/bareos/bareos-dir.d/filesets.conf
@/etc/bareos/bareos-dir.d/jobs.conf

Director {
  Name = moops-dir
  QueryFile = /usr/lib/bareos/scripts/query.sql
  Maximum Concurrent Jobs = 10
  Password = "PUT_ORIGINAL_VALUE_HERE"  # Console password
  Messages = Daemon
  Auditing = yes
}

Client {
  Name = moops-fd
  Address = moops.myhome.net
  Password = "PUT_ORIGINAL_VALUE_HERE"
}

Storage {
  Name = Tape
  Address = moops.myhome.net
  Auto Changer = yes
  Password = "PUT_ORIGINAL_VALUE_HERE"
  Device = PV-124T
  Media Type = LTO-3
}

Storage {
  Name = File
  Address = moops.myhome.net
  Password = "PUT_ORIGINAL_VALUE_HERE"
  Device = FileStorage
  Media Type = File
}

Catalog {
  Name = Catalog
  dbdriver = mysql
  dbname = "PUT_ORIGINAL_VALUE_HERE"
  dbuser = "PUT_ORIGINAL_VALUE_HERE"
  dbpassword = "PUT_ORIGINAL_VALUE_HERE"
}

Messages {
  Name = Standard
  console = all, !skipped, !saved, !audit
  append = "/var/log/bareos/bareos.log" = all, !skipped, !audit
  catalog = all, !audit
}

Messages {
  Name = Daemon
  console = all, !skipped, !saved, !audit
  append = "/var/log/bareos/bareos.log" = all, !skipped, !audit
  append = "/var/log/bareos/bareos-audit.log" = audit
}

Pool {
  Name = Full
  AutoPrune = yes
  Label Format = Full-
  Pool Type = Backup
  Recycle = yes
  VolumeRetention = 20d
  VolumeUseDuration = 3d
}

Pool {
  Name = Scratch
  Pool Type = Backup
}

Start Services

Everything should work.

sudo systemctl start bareos-fd.service
sudo systemctl start bareos-sd.service
sudo systemctl start bareos-dir.service
sudo systemctl status bareos-fd.service
sudo systemctl status bareos-sd.service
sudo systemctl status bareos-dir.service

Test Everything

Here we’ll do a quick test. We’ll create a bunch of files in /home/bareos/selftest (defined in /etc/bareos/bareos-dir.d/filesets.conf) and back them up to one or two tapes. Then we’ll restore them to /home/bareos/tmp/restores (defined in /etc/bareos/bareos-dir.d/jobs.conf). We’ll compare them with sha1sum.

Tip

Since we’re starting with an empty Bareos database, it will consider all tapes empty. Remove any tapes from the autoloader that you don’t want overridden. You can use my tape_bulk_eject.py tool to automate this.

# Create files.
rm -rf /home/bareos/selftest; mkdir /home/bareos/selftest
date |tee /home/bareos/selftest/current_date.txt
openssl rand -base64 $(( 2**30 * 3/4 * 2 )) -out /home/bareos/selftest/2_gb_random.bin
mkdir -p /home/bareos/selftest/subdir1/subdir2
(cd /home/bareos/selftest; for i in {1..15}; do cat 2_gb_random.bin >> subdir1/subdir2/30_gb_random.bin; done)
find /home/bareos/selftest -type f -exec sha1sum {} \+

# Backup through bconsole.
sudo bconsole

In the Bareos console we’ll type these commands to backup the above files and then restore them to a separate directory. Remove any tapes from the drive.

update slots  # Read the status of all slots in the autoloader.
label barcodes  # Initialize all tapes. Select Full pool. ETA 30 mins for 16 tapes.
list volumes  # Verify all tapes have been detected.
run BackupSelfTest
status client  # Check the status of the job. You can also run "messages".
restore  # After backup is done do this. Follow the directions.
q

Finally run find /home/bareos/tmp/restores/home/bareos/selftest/ -type f -exec sha1sum {} \+ and compare sha sums. You can test if your data is actually encrypted by temporarily removing the PKI lines from bareos-fd.conf and running the restore command again.

Reusing Old Tapes

Several years ago before Bareos I used Bacula. I consider the data on my old tapes as disposable and I want to start fresh. Unfortunately Bareos (and Bacula) doesn’t have an easy way to reuse tapes. The best method I’ve found was to manually wipe them. I run these commands:

# Stop Bareos services.
for s in dir sd fd; do sudo systemctl stop bareos-$s.service; done
# Make sure drive is unlocked and unloaded. Also which slots tapes are in.
sudo mtx -f /dev/sg3 status
# Wipe selected tapes. Here {1..16} expands to all 16 slots.
for t in {1..16}; do
    sudo mtx -f /dev/sg3 load $t 0
    sudo mt -f /dev/nst0 weof
    sudo mtx -f /dev/sg3 unload $t 0
done

Backing Up Data

These are the commands I run to backup my data.

# On the client.
rsync -irtv --delete Main Old moops:/home/bareos/bosco
# On the server.
sudo su -c 'for f in /sys/class/scsi_host/host*/scan; do echo "- - -" > $f; done'
lsscsi -g  # Verify autoloader and tape drive are present.
sudo systemctl start mariadb.service
for s in fd sd dir; do sudo systemctl start bareos-$s.service; done
sudo mtx -f /dev/sg3 status  # Verify tape drive (element 0) is empty.
sudo bconsole
# In bconsole on the server.
update slots
# New tapes: label slot=8,12,14-16 barcodes
list volumes
run job=BackupBoscoMain
run job=BackupBoscoOld
run job=BackupCatalog
status client

Once all three jobs finish (you can queue them up at the same time) you’re done. I always eject all tapes and store them off-site, so I run these commands within bconsole:

unmount Tape  # Unloads the last tape from the drive.
list jobs
list volumes jobid=1 jobid=2 jobid=3

Finally you’ll want to backup your Bareos database somewhere in case you need to restore the catalog on another machine or if you lose your Bareos/MySQL server. You only need to do this if you encrypt your tapes.

sudo cat /var/lib/bareos/bareos.sql |gzip -9 > ~/bareos.sql.gz
sudo rm /var/lib/bareos/bareos.sql

Then I use my tape_bulk_eject.py tool to eject all those tapes. I also stop all services since I don’t leave my autoloader running all the time (it’s too loud for my living room).

for s in dir sd fd; do sudo systemctl stop bareos-$s.service; done
sudo systemctl stop mariadb.service
./tape_bulk_eject.py "000039L3|000031L3" "000031L3|000021L3|000032L3|000033L3|000030L3"

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