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SUSE Linux Enterprise Server 15

WordPress on LAMP on SUSE Linux Enterprise Server — Getting Started

This guide helps users install and configure WordPress using the LAMP stack on SUSE Linux Enterprise Server.

Disclaimer: Documents published as part of the SUSE Best Practices and the Technical Reference Documentation series have been contributed voluntarily by SUSE employees and third parties. They are meant to serve as examples of how particular actions can be performed. They have been compiled with utmost attention to detail. However, this does not guarantee complete accuracy. SUSE cannot verify that actions described in these documents do what is claimed or whether actions described have unintended consequences. SUSE LLC, its affiliates, the authors, and the translators may not be held liable for possible errors or the consequences thereof.

Author: James Yang, SUSE
Publication Date: 2021-11-17

1 Scope

The LAMP stack, while simple, is ubiquitous. Its popularity in demos and tutorials all over the Internet to introduce a new concept or explain a complex one is like no other. This guide details how to install and configure MariaDB, Apache, PHP on SUSE Linux Enterprise Server to compose the LAMP stack. To demonstrate the LAMP stack is functional, WordPress will be installed and configured to use the stack. The audience is expected to have a basic familiarity of Linux and be comfortable using the command line interface. The result is not intended for production scenarios but rather for workshops or demos.

1.1 The LAMP stack

The term LAMP stands for the components:

  • Linux - SUSE Linux Enterprise Server Operating System

  • Apache - HTTP Server

  • MySQL / MariaDB - Relational Database

  • PHP / Python / Perl - Programming Language

The below graphic roughly visualizes what the stack looks like when completed.

TRD wordpress on lamp on sles one tier
Figure 1: WordPress LAMP stack architecture

1.2 MariaDB and MySQL

Starting with SUSE Linux Enterprise Server 12, MySQL has been replaced with MariaDB. MariaDB’s client protocol is "wire" compatible with MySQL’s protocol and in most scenarios even the data files are binary compatible. For our purposes, MariaDB will work fine (and still spells LAMP!). For more information, visit MariaDB versus MySQL: Compatibility.

2 Preinstallation / prerequisites

2.1 System requirements

  • CPU with 1 core

  • AMD64/Intel 64 architecture

  • 2 GB disk space

  • 2 GB RAM

  • an installation of SUSE Linux Enterprise Server

Note
Note

These requirements cover a minimal installation. Adapt as needed to cover your use case.

2.2 Registering the server

Before starting, ensure your SUSE Linux Enterprise Server instance is registered by following this knowledge base article to enable access to repositories. If you are using one of SUSE’s "pay-as-you-go" respective "on-demand" images on one of the public cloud providers, you may omit this step.

2.3 Refreshing repositories

  1. Prior to starting the installation, refresh your repositories to ensure you have the latest packages to install.

sudo zypper update --no-confirm
Refreshing service 'Basesystem_Module_15_SP3_x86_64'.
Refreshing service 'SUSE_Linux_Enterprise_Server_15_SP3_x86_64'.
Refreshing service 'Server_Applications_Module_15_SP3_x86_64'.
Loading repository data...
Reading installed packages...
Resolving package dependencies...
...

3 Installing and configuring the components

3.1 Setting up MariaDB

Start with the MariaDB installation. This includes verifying a successful installation, starting up MariaDB, and creating a database along with an associated user for WordPress to use. MariaDB will store all the data in your WordPress application.

  1. Install the MariaDB package. The --no-confirm option bypasses the user confirmation to install.

    sudo zypper install --no-confirm mariadb
    Refreshing service 'Basesystem_Module_15_SP3_x86_64'.
    Refreshing service 'SUSE_Linux_Enterprise_Server_15_SP3_x86_64'.
    Refreshing service 'Server_Applications_Module_15_SP3_x86_64'.
    Loading repository data...
    Reading installed packages...
    Resolving package dependencies...
    
    The following 9 NEW packages are going to be installed:
      libJudy1 libmariadb3 libpq5 mariadb mariadb-client mariadb-errormessages psqlODBC python3-mysqlclient unixODBC
    
    The following 2 recommended packages were automatically selected:
      mariadb psqlODBC
    
    9 new packages to install.
    Overall download size: 23.7 MiB. Already cached: 0 B. After the operation, additional 171.2 MiB will be used.
    Continue? [y/n/v/...? shows all options] (y): y
    Retrieving package libmariadb3-3.1.13-3.30.1.x86_64                                                                                             (1/9), 132.3 KiB (354.9 KiB unpacked)
    ...
  2. Enable MariaDB to start automatically on boot (optional).

    sudo systemctl enable mariadb
    Created symlink /etc/systemd/system/mysql.service → /usr/lib/systemd/system/mariadb.service.
    Created symlink /etc/systemd/system/multi-user.target.wants/mariadb.service → /usr/lib/systemd/system/mariadb.service.
  3. Start MariaDB.

    sudo systemctl start mariadb
  4. Check to see that MariaDB actually started. The Active output field should read active(running).

    sudo systemctl status mariadb
    ● mariadb.service - MariaDB database server
       Loaded: loaded (/usr/lib/systemd/system/mariadb.service; disabled; vendor preset: disabled)
       Active: active (running) since Fri 2021-07-02 01:55:22 UTC; 7s ago
         Docs: man:mysqld(8)
               https://mariadb.com/kb/en/library/systemd/
      Process: 26513 ExecStartPre=/usr/lib/mysql/mysql-systemd-helper upgrade (code=exited, status=0/SUCCESS)
      Process: 26447 ExecStartPre=/usr/lib/mysql/mysql-systemd-helper install (code=exited, status=0/SUCCESS)
     Main PID: 26519 (mysqld)
       Status: "Taking your SQL requests now..."
        Tasks: 30
       CGroup: /system.slice/mariadb.service
               └─26519 /usr/sbin/mysqld --defaults-file=/etc/my.cnf --user=mysql
  5. Verify you can connect to MariaDB with the mariadb client. The -u flag selects the user to log in as. Use the root user since no other users exist yet (except the default user discussed below ([default-user])). The MariaDB [(none)]> prompt indicates you are now in the MariaDB shell with no default database, hence "none".

    mariadb -u root
    Welcome to the MariaDB monitor.  Commands end with ; or \g.
    Your MariaDB connection id is 3
    Server version: 10.5.11-MariaDB MariaDB package
    
    Copyright (c) 2000, 2018, Oracle, MariaDB Corporation Ab and others.
    
    Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
    
    MariaDB [(none)]>
  6. The MariaDB installation comes with a pesky default user that can mask login attempts from other users from localhost. While still in the MariaDB shell, remove this user.

    DROP USER ''@localhost;

    For example:

    MariaDB [(none)]> DROP USER ''@localhost;
    Query OK, 0 rows affected (0.003 sec)
  7. Now create a database for WordPress and a corresponding user. Replace password with your own password. Exit the MariaDB shell when completed.

    CREATE DATABASE IF NOT EXISTS wordpress;
    GRANT ALL PRIVILEGES ON wordpress.* TO 'wordpress' IDENTIFIED BY 'password';
    exit;

    For example:

    MariaDB [(none)]> CREATE DATABASE IF NOT EXISTS wordpress;
    Query OK, 1 row affected (0.000 sec)
    
    MariaDB [(none)]> GRANT ALL PRIVILEGES ON wordpress.* TO 'wordpress' IDENTIFIED BY 'password';
    Query OK, 0 rows affected (0.003 sec)
    
    MariaDB [(none)]> exit
    Bye
  8. Verify you can connect as the WordPress user. Replace password with your own password.

    mariadb -u wordpress -p wordpress
    Enter password:
    Welcome to the MariaDB monitor.  Commands end with ; or \g.
    Your MariaDB connection id is 4
    Server version: 10.5.11-MariaDB MariaDB package
    
    Copyright (c) 2000, 2018, Oracle, MariaDB Corporation Ab and others.
    
    Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
    
    MariaDB [wordpress]>
  9. You have completed the MariaDB section. Exit the MariaDB shell.

    exit

    For example:

    MariaDB [wordpress]> exit
    Bye

3.2 Setting up Apache HTTP server

Next, set up the Apache server. Apache server is used to host and serve the WordPress content. In this section, you will install Apache server and configure it to start on boot.

  1. Install the apache2 package.

    zypper install --no-confirm apache2
    Refreshing service 'Basesystem_Module_15_SP3_x86_64'.
    Refreshing service 'SUSE_Linux_Enterprise_Server_15_SP3_x86_64'.
    Refreshing service 'Server_Applications_Module_15_SP3_x86_64'.
    Refreshing service 'Web_and_Scripting_Module_15_SP3_x86_64'.
    Loading repository data...
    Reading installed packages...
    Resolving package dependencies...
    
    The following 2 NEW packages are going to be installed:
      apache2 apache2-prefork
    
    2 new packages to install.
    Overall download size: 1.6 MiB. Already cached: 0 B. After the operation, additional 4.9 MiB will be used.
    Continue? [y/n/v/...? shows all options] (y): y
    Retrieving package apache2-2.4.43-3.22.1.
    ...
  2. Enable the apache2 service to start on boot (optional).

    systemctl enable apache2
    Created symlink /etc/systemd/system/httpd.service → /usr/lib/systemd/system/apache2.service.
    Created symlink /etc/systemd/system/apache.service → /usr/lib/systemd/system/apache2.service.
    Created symlink /etc/systemd/system/multi-user.target.wants/apache2.service → /usr/lib/systemd/system/apache2.service.

3.3 Setting up PHP

With Apache installed, continue with PHP. WordPress is written in PHP as the main scripting language which in conjunction with the Apache PHP module enables rendering HTML pages for browsers to display. This section details how to enable the Web and Scripting Module, install PHP, install the Apache PHP module, and finally configure Apache to handle PHP files.

  1. First, you need the Web and Scripting Module which is included with your SUSE Linux Enterprise Server subscription. The Web and Scripting Module contains common tools such as php, python, node.js for hosting Web applications. SUSEConnect allows you to enable this module. The --product option configures the module. Substitute it with your specific SUSE Linux Enterprise Server version, {sles_version} and system architecture, {architecture}.

    > sudo SUSEConnect --product sle-module-web-scripting/{sles_version}/{architecture}

    For example:

    sudo SUSEConnect --product sle-module-web-scripting/15.3/x86_64
    Registering system to SUSE Customer Center
    
    Updating system details on https://scc.suse.com ...
    
    Activating sle-module-web-scripting 15.3 x86_64 ...
    -> Adding service to system ...
    -> Installing release package ...
    
    Successfully registered system
  2. Now install PHP and the Apache PHP module which will be needed later on.

    sudo zypper install -y php php-mysql php-zlib apache2-mod_php7
    Refreshing service 'Basesystem_Module_15_SP3_x86_64'.
    Refreshing service 'SUSE_Linux_Enterprise_Server_15_SP3_x86_64'.
    Refreshing service 'Server_Applications_Module_15_SP3_x86_64'.
    Refreshing service 'Web_and_Scripting_Module_15_SP3_x86_64'.
    Loading repository data...
    Reading installed packages...
    Resolving package dependencies...
    
    The following 13 NEW packages are going to be installed:
      apache2-mod_php7 php7 php7-ctype php7-dom php7-iconv php7-json php7-mysql php7-pdo php7-sqlite php7-tokenizer php7-xmlreader php7-xmlwriter php7-zlib
    
    The following 8 recommended packages were automatically selected:
      php7-ctype php7-dom php7-iconv php7-json php7-sqlite php7-tokenizer php7-xmlreader php7-xmlwriter
    
    The following 3 packages are suggested, but will not be installed:
      php7-gd php7-gettext php7-mbstring
    
    13 new packages to install.
    Overall download size: 3.7 MiB. Already cached: 0 B. After the operation, additional 20.5 MiB will be used.
    Continue? [y/n/v/...? shows all options] (y): y
    ...
  3. Test your PHP installation.

    php --version
    PHP 7.4.6 (cli) ( NTS )
    Copyright (c) The PHP Group
    Zend Engine v3.4.0, Copyright (c) Zend Technologies
  4. Enable the Apache PHP module with a2enmod.

    a2enmod php7
  5. Associate PHP files with the application/x-httpd-php content type so that PHP files are rendered on the client.

    echo -e "AddType application/x-httpd-php .php\n" >> /etc/apache2/mod_mime-defaults.conf

3.4 Setting up WordPress

The final component in your stack is WordPress. This section explains where to download and how to install and configure WordPress to connect to MariaDB.

  1. First, download WordPress.

    curl -L https://wordpress.org/latest.zip -o /opt/wordpress_latest.zip
      % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                     Dload  Upload   Total   Spent    Left  Speed
    100 15.7M  100 15.7M    0     0  3209k      0  0:00:05  0:00:05 --:--:-- 3510k
  2. Extract the zip file.

    unzip /opt/wordpress_latest.zip -d /opt
    Archive:  /opt/wordpress_latest.zip
       creating: /opt/wordpress/wordpress/
      inflating: /opt/wordpress/wordpress/xmlrpc.php
      inflating: /opt/wordpress/wordpress/wp-blog-header.php
      inflating: /opt/wordpress/wordpress/readme.html
    ...
  3. By default Apache serves documents from /srv/www/htdocs, so move the WordPress contents there.

    mv wordpress/* /srv/www/htdocs/
  4. Create a copy of the wp-config PHP configuration file. Apply your installation-specific settings.

    cp /srv/www/htdocs/wp-config-sample.php /src/www/htdocs/wp-config.php
  5. Now update the configuration with the database setttings. Replace password with your password.

    sed -i 's/database_name_here/wordpress/' /srv/www/htdocs/wp-config.php
    sed -i 's/username_here/wordpress/' /srv/www/htdocs/wp-config.php
    sed -i 's/password_here/password/' /srv/www/htdocs/wp-config.php

3.5 Configuring firewalld

You may need to open port 80 on the firewall to allow clients to connect to Apache. If you are not using a firewall, or if it is disabled, skip this section.

  1. To check if firewalld (firewall service) is running, use systemctl.

    systemcl status firewalld

    If no firewall service is found, proceed to the next section.

    Unit firewalld.service could not be found.

    Otherwise, if it is running as shown below, continue to the next step to open port 80.

    ● firewalld.service - firewalld - dynamic firewall daemon
         Loaded: loaded (/usr/lib/systemd/system/firewalld.service; enabled; vendor preset: disabled)
         Active: active (running) since Fri 2021-10-29 19:10:33 PDT; 28min ago
           Docs: man:firewalld(1)
       Main PID: 858 (firewalld)
          Tasks: 2
         CGroup: /system.slice/firewalld.service
                 └─858 /usr/bin/python3 /usr/sbin/firewalld --nofork --nopid
    
    Oct 29 19:10:31 localhost systemd[1]: Starting firewalld - dynamic firewall daemon...
    Oct 29 19:10:33 localhost systemd[1]: Started firewalld - dynamic firewall daemon.
  2. Add the HTTP service to the firewall permanently.

    firewall-cmd --permanent --add-service http
    You''re performing an operation over default zone ('external'),
    but your connections/interfaces are in zone 'docker' (see --get-active-zones)
    You most likely need to use --zone=docker option.
    
    success
  3. Reload the firewall to apply the changes.

    firewall-cmd --reload
    success

3.6 Starting the system

  1. Everything should be configured now. Start the Apache server.

    systemctl start apache2
  2. Open a browser with your server IP or host name at http://hostname. If the installation was successful, you should be presented with the WordPress installation page.

TRD wordpress on lamp on sles wordpress installation page
Figure 2: WordPress Installation Page

4 Two-tier architecture

You can create a two-tier architecture and separate the database server from the application server as shown in the graphic below:

TRD wordpress on lamp on sles two tier
Figure 3: Two-Tier WordPress LAMP stack

Only a few additional steps are needed to do so. As before, ensure both servers are registered (Section 2.2, “Registering the server”) before starting.

4.1 Database server

On the database server, make the following changes:

  1. Repeat the previous steps for Section 3.1, “Setting up MariaDB”.

  2. MariaDB binds only to the loopback interface by default. Change it to bind to all addresses.

    sed -i 's/= 127.0.0.1/= 0.0.0.0/' /etc/my.cnf
  3. Restart MariaDB so it picks up the changes.

    systemctl restart mariadb
  4. Open port 3306 (default for MariaDB) to enable the clients to connect. Skip this step if you are not using a firewall.

    firewall-cmd --add-port 3306/tcp --permanent
    success

4.2 Application server

On the application server, perform the following steps:

  1. Verify the application server has connectivity to MariaDB on the database server.

    nc -vz ${ip of database server} 3306

    For example:

    >  nc -vz 10.0.0.40 3306
    Connection to 10.0.0.40 3306 port [tcp/mysql] succeeded!
  2. Then repeat the previous steps as explained in Section 3.2, “Setting up Apache HTTP server”, Section 3.3, “Setting up PHP”, Section 3.4, “Setting up WordPress” and in Section 3.5, “Configuring firewalld.

  3. One additional step is required to point WordPress at the database server. Replace application_server_ip with the IP address of your MariaDB server.

    sed -i "s/'DB_HOST', 'localhost'/'DB_HOST', '${application_server_ip}'/" /srv/www/htdocs/wp-config.php

    For example:

    > sed -i "s/'DB_HOST', 'localhost'/'DB_HOST', '10.0.0.40'/" /srv/www/htdocs/wp-config.php
  4. Visit http://application_server_ip with a browser to check if your setup was successful.

5 Appendix

5.1 Debugging WordPress

  1. If you need to diagnose why a WordPress page will not load, it can be insightful to enable WordPress debugging. To enable WordPress debugging, set WP_DEBUG to true in wp-config.php:

    sed -i "s/'WP_DEBUG', false/'WP_DEBUG', true/" /srv/www/htdocs/wp-config.php

    Then reload the page. This will enable printing the output of PHP errors and warnings on the page. In the example below, an incorrect password was used which caused MariaDB to return an error to the PHP client. With debugging enabled, the error message can be viewed without accessing the server directly.

    TRD wordpress on lamp on sles debugging
    Figure 4: WordPress on LAMP Debugging

    For more details on further WordPress debugging, see WordPress debugging.

  2. To revert WordPress debugging, simply set WP_DEBUG back to false.

    sed -i "s/'WP_DEBUG', true/'WP_DEBUG', false/" /srv/www/htdocs/wp-config.php

7 GNU Free Documentation License

Copyright © 2000, 2001, 2002 Free Software Foundation, Inc. 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. Everyone is permitted to copy and distribute verbatim copies of this license document, but changing it is not allowed.

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This License is a kind of "copyleft", which means that derivative works of the document must themselves be free in the same sense. It complements the GNU General Public License, which is a copyleft license designed for free software.

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  14. Do not retitle any existing section to be Entitled "Endorsements" or to conflict in title with any Invariant Section.

  15. Preserve any Warranty Disclaimers.

If the Modified Version includes new front-matter sections or appendices that qualify as Secondary Sections and contain no material copied from the Document, you may at your option designate some or all of these sections as invariant. To do this, add their titles to the list of Invariant Sections in the Modified Version’s license notice. These titles must be distinct from any other section titles.

You may add a section Entitled "Endorsements", provided it contains nothing but endorsements of your Modified Version by various parties—​for example, statements of peer review or that the text has been approved by an organization as the authoritative definition of a standard.

You may add a passage of up to five words as a Front-Cover Text, and a passage of up to 25 words as a Back-Cover Text, to the end of the list of Cover Texts in the Modified Version. Only one passage of Front-Cover Text and one of Back-Cover Text may be added by (or through arrangements made by) any one entity. If the Document already includes a cover text for the same cover, previously added by you or by arrangement made by the same entity you are acting on behalf of, you may not add another; but you may replace the old one, on explicit permission from the previous publisher that added the old one.

The author(s) and publisher(s) of the Document do not by this License give permission to use their names for publicity for or to assert or imply endorsement of any Modified Version.

5. COMBINING DOCUMENTS

You may combine the Document with other documents released under this License, under the terms defined in section 4 above for modified versions, provided that you include in the combination all of the Invariant Sections of all of the original documents, unmodified, and list them all as Invariant Sections of your combined work in its license notice, and that you preserve all their Warranty Disclaimers.

The combined work need only contain one copy of this License, and multiple identical Invariant Sections may be replaced with a single copy. If there are multiple Invariant Sections with the same name but different contents, make the title of each such section unique by adding at the end of it, in parentheses, the name of the original author or publisher of that section if known, or else a unique number. Make the same adjustment to the section titles in the list of Invariant Sections in the license notice of the combined work.

In the combination, you must combine any sections Entitled "History" in the various original documents, forming one section Entitled "History"; likewise combine any sections Entitled "Acknowledgements", and any sections Entitled "Dedications". You must delete all sections Entitled "Endorsements".

6. COLLECTIONS OF DOCUMENTS

You may make a collection consisting of the Document and other documents released under this License, and replace the individual copies of this License in the various documents with a single copy that is included in the collection, provided that you follow the rules of this License for verbatim copying of each of the documents in all other respects.

You may extract a single document from such a collection, and distribute it individually under this License, provided you insert a copy of this License into the extracted document, and follow this License in all other respects regarding verbatim copying of that document.

7. AGGREGATION WITH INDEPENDENT WORKS

A compilation of the Document or its derivatives with other separate and independent documents or works, in or on a volume of a storage or distribution medium, is called an "aggregate" if the copyright resulting from the compilation is not used to limit the legal rights of the compilation’s users beyond what the individual works permit. When the Document is included in an aggregate, this License does not apply to the other works in the aggregate which are not themselves derivative works of the Document.

If the Cover Text requirement of section 3 is applicable to these copies of the Document, then if the Document is less than one half of the entire aggregate, the Document’s Cover Texts may be placed on covers that bracket the Document within the aggregate, or the electronic equivalent of covers if the Document is in electronic form. Otherwise they must appear on printed covers that bracket the whole aggregate.

8. TRANSLATION

Translation is considered a kind of modification, so you may distribute translations of the Document under the terms of section 4. Replacing Invariant Sections with translations requires special permission from their copyright holders, but you may include translations of some or all Invariant Sections in addition to the original versions of these Invariant Sections. You may include a translation of this License, and all the license notices in the Document, and any Warranty Disclaimers, provided that you also include the original English version of this License and the original versions of those notices and disclaimers. In case of a disagreement between the translation and the original version of this License or a notice or disclaimer, the original version will prevail.

If a section in the Document is Entitled "Acknowledgements", "Dedications", or "History", the requirement (section 4) to Preserve its Title (section 1) will typically require changing the actual title.

9. TERMINATION

You may not copy, modify, sublicense, or distribute the Document except as expressly provided for under this License. Any other attempt to copy, modify, sublicense or distribute the Document is void, and will automatically terminate your rights under this License. However, parties who have received copies, or rights, from you under this License will not have their licenses terminated so long as such parties remain in full compliance.

10. FUTURE REVISIONS OF THIS LICENSE

The Free Software Foundation may publish new, revised versions of the GNU Free Documentation License from time to time. Such new versions will be similar in spirit to the present version, but may differ in detail to address new problems or concerns. See http://www.gnu.org/copyleft/.

Each version of the License is given a distinguishing version number. If the Document specifies that a particular numbered version of this License "or any later version" applies to it, you have the option of following the terms and conditions either of that specified version or of any later version that has been published (not as a draft) by the Free Software Foundation. If the Document does not specify a version number of this License, you may choose any version ever published (not as a draft) by the Free Software Foundation.

ADDENDUM: How to use this License for your documents

Copyright (c) YEAR YOUR NAME.
   Permission is granted to copy, distribute and/or modify this document
   under the terms of the GNU Free Documentation License, Version 1.2
   or any later version published by the Free Software Foundation;
   with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts.
   A copy of the license is included in the section entitled “GNU
   Free Documentation License”.

If you have Invariant Sections, Front-Cover Texts and Back-Cover Texts, replace the “ with…​Texts.” line with this:

with the Invariant Sections being LIST THEIR TITLES, with the
   Front-Cover Texts being LIST, and with the Back-Cover Texts being LIST.

If you have Invariant Sections without Cover Texts, or some other combination of the three, merge those two alternatives to suit the situation.

If your document contains nontrivial examples of program code, we recommend releasing these examples in parallel under your choice of free software license, such as the GNU General Public License, to permit their use in free software. oc[]

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