VERITAS Cluster Server Traffic Director Release Notes

VERITAS Cluster Server Traffic Director Release Notes
VERITAS Cluster Server 4.0
Traffic Director
Release Notes
Linux
August 2004
Disclaimer
The information contained in this publication is subject to change without notice. VERITAS Software
Corporation makes no warranty of any kind with regard to this manual, including, but not limited to,
the implied warranties of merchantability and fitness for a particular purpose. VERITAS Software
Corporation shall not be liable for errors contained herein or for incidental or consequential damages
in connection with the furnishing, performance, or use of this manual.
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Logo, and all other VERITAS product names and slogans are trademarks or registered trademarks of
VERITAS Software Corporation. VERITAS and the VERITAS logo, Reg. U.S. Pat. & Tm. Off. Other
product names and/or slogans mentioned herein may be trademarks or registered trademarks of their
respective companies.
VERITAS Software Corporation
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Mountain View, CA 94043
USA
Phone 650–527–8000 Fax 650–527–2908
www.veritas.com
Third-Party Copyrights
SNMP Copyright Notice
SNMP support in VCS is based on CMU SNMP v2 under the following copyright:
Copyright 1989, 1991, 1992 by Carnegie Mellon University
All Rights Reserved
Permission to use, copy, modify, and distribute this software and its documentation for any purpose and without fee is hereby granted, provided
that the above copyright notice appear in all copies and that both that copyright notice and this permission notice appear in supporting
documentation, and that the name of CMU not be used in advertising or publicity pertaining to distribution of the software without specific,
written prior permission.
CMU DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF
MERCHANTABILITY AND FITNESS,
IN NO EVENT SHALL CMU BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
Data Encryption Standard (DES) Copyright Notice
Support for data encryption in VCS is based on the MIT Data Encryption Standard (DES) under the following copyright:
Copyright (c) 1990 Dennis Ferguson. All rights reserved.Commercial use is permitted only if products which are derived from or include this
software are made available for purchase and/or use in Canada. Otherwise, redistribution and use in source and binary forms are permitted.
Copyright 1985, 1986, 1987, 1988, 1990 by the Massachusetts Institute of Technology. All Rights Reserved.
Export of this software from the United States of America may require a specific license from the United States Government. It is the responsibility
of any person or organization contemplating export to obtain such a license before exporting.
WITHIN THAT CONSTRAINT, permission to use, copy, modify, and distribute this software and its documentation for any purpose and without
fee is hereby granted, provided that the above copyright notice appear in all copies and that both that copyright notice and this permission notice
appear in supporting documentation, and that the name of M.I.T. not be used in advertising or publicity pertaining to distribution of the software
without specific, written prior permission. M.I.T. makes no representations about the suitability of this software for any purpose. It is provided "as
is" without expressor implied warranty.
Apache Software Copyright Notice
This product includes software developed by the Apache Software Foundation (http://www.apache.org/).
The Apache Software License, Version 1.1
Copyright (c) 1999 The Apache Software Foundation. All rights reserved.
Redistribution and use in source and binary forms, with or without modification,
are permitted provided that the following conditions are met:
1. Redistributions of source code must retain the above copyright notice,
this list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright
notice, this list of conditions and the following disclaimer in the
documentation and/or other materials provided with the distribution.
3. The end-user documentation included with the redistribution, if any,
must include the following acknowledgement:
"This product includes software developed by the Apache
Software Foundation (http://www.apache.org/)."
Alternately, this acknowledgement may appear in the software itself, if and
wherever such third-party acknowledgements normally appear.
4. The names "The Jakarta Project", "Tomcat", and "Apache Software Foundation" must
not be used to endorse or promote products derived from this software without
prior written permission. For written permission, please contact apache@apache.org.
5. Products derived from this software may not be called "Apache" nor
may "Apache" appear in their names without prior written permission
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THIS SOFTWARE IS PROVIDED ‘‘AS IS’’ AND ANY EXPRESSED OR IMPLIED
WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION
OR ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
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ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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OF SUCH DAMAGE.
=================================================================
This software consists of voluntary contributions made by many individuals
on behalf of the Apache Software Foundation. For more information on the
Apache Software Foundation, please see
<http://www.apache.org/>.
VCS Traffic Director 4.0 Release Notes
VERITAS Cluster Server Traffic Director (VCS Traffic Director) is a load-balancing solution for
highly available cluster configurations. VCS Traffic Director offers intelligent traffic management
for users needing scalable clusters.
This document provides important information regarding VCS Traffic Director 4.0 for Intel 686
Architecture running a complete installation of Red Hat Linux. Please review this entire document
before installing VCS Traffic Director.
Release Notes: Topics
This document covers the following topics:
◆
Packages Installed
◆
Confirming Hardware and Software Compatibility
◆
Operational Notes
◆
Known Issues
◆
Software Limitations
◆
Documentation
◆
Getting Help
1
Packages Installed
Packages Installed
The packages for VCS Traffic Director are in the traffic_director/rpms directory on the
disc containing VCS Traffic Director:
◆
VRTStd, VCS Traffic Director
◆
VRTStdw, VCS Traffic Director (Web Console)
◆
VRTStddoc, VCS Traffic Director Documentation
VCS Traffic Director also installs the following VERITAS Cluster Server packages:
2
◆
VRTScscm, VCS Cluster Manager (Java Console)
◆
VRTSgab, Group Membership and Atomic Broadcast
◆
VRTSllt, Low Latency Transport
◆
VRTSperl, Perl for VRTSvcs
◆
VRTSvcs, VERITAS Cluster Server
◆
VRTSvcsag, VCS Bundled Agents
◆
VRTSvcsmg, VCS Message Catalogs
◆
VRTSvcsmn, VCS Manual Pages
◆
VRTSvcsw, Cluster Manager (Web Console)
◆
VRTSvlic, VERITAS License Utilities
◆
VRTSweb, VERITAS Web GUI Engine
◆
VRTSvcsdc, VCS Documentation
◆
VRTSjre, VERITAS JRE Redistribution
VCS Traffic Director Release Notes
Confirming Hardware and Software Compatibility
Confirming Hardware and Software Compatibility
The compatibility list contains the latest information about supported hardware and software and is
updated regularly.
Note Before installing VCS Traffic Director 4.0, review the current compatibility list to confirm
the compatibility of your hardware and software.
You can find the current compatibility list on the VERITAS Support Web site:
http://support.veritas.com.
If you don't find your hardware or software listed or if you have questions about the information in
the compatibility list, please contact VERITAS Support.
System Requirements
VCS Traffic Director 4.0 requires:
◆
Two Intel 686 Architecture systems running a complete installation of Red Hat Enterprise
Linux 3.0 (32-bit only). Distributions supported: 2.4.21-15.EL, 2.4.21-15.ELsmp and
2.4.21-15.ELhugemem.
◆
Public network and private network NICs identified
◆
At least 256 MB RAM memory
◆
At least 250 MB disk space for VCS/TD combination
◆
No shared storage configured on VCS running on these nodes
Back-end Servers
◆
◆
Back-end servers can be any system, including those running one of the following operating
systems:
◆
Solaris
◆
MS Windows
◆
Linux
◆
HP-UX
◆
AIX
Back-end servers must be connected to the VCS Traffic Director machines.
3
Operational Notes
Supported Software
The following software items are supported and required to run the VCS Traffic Director 4.0
software:
◆
◆
Red Hat Enterprise Linux 3.0 (32-bit)
VERITAS Cluster Server (VCS) 4.0 is installed with VCS Traffic Director if it is not found to
be already installed by the installer.
VCS Traffic Director Web Console Requirements
Requirements for the VCS Traffic Director Web Console are as follows:
◆
The minimum supported screen size is 800 x 600. Use of smaller screen sizes or browser
windows may result in colliding fields.
◆
Applets do not work properly on Netscape if JVM 1.3 is installed.
◆
The following supported Internet browsers have been tested:
◆
Internet Explorer 5.0, 5.5, 6.0
◆
Netscape 6.2, 7.0, 7.2
Operational Notes
Installing
Refer to the VERITAS Cluster Server Traffic Director Installation Guide for instructions on how to
install VCS Traffic Director 4.0. The VERITAS Cluster Server Traffic Director Installation Guide is
in the /docs directory of the disc containing VCS Traffic Director.
When running tdsetup, use a terminal large enough to see 30 lines. Some of the screens have
navigation usage for arrows and the spacebar on line 29 out of 30 lines. These instructions are
hidden if the default terminal size is 25 lines.
Using VCS Traffic Director in a Multiple-node Cluster
The VCS Traffic Director option may also be used on two dedicated nodes of a larger VCS cluster
as well as on a dedicated two-node VCS cluster. Requirements and limitations for this
configuration are explained fully in the Appendix of the VCS Traffic Director Installation Guide.
4
VCS Traffic Director Release Notes
Operational Notes
Displaying the License Key
Type the following command to display all license keys currently installed on a system:
# /opt/VRTSvlic/bin/vxlicrep
Output resembles:
VERITAS License Manager vxlicrep utility version 3.02.006
Copyright (C) 1996-2004 VERITAS Software Corp. All Rights reserved.
Creating a report on all VERITAS products installed on this system
-----------------***********************----------------License Key = XXXX-XXXX-XXXX-XXXX-XXXX-XXXX-X
Product Name = VERITAS Cluster Server
License Type = DEMO
OEM ID
= 100
Demo End Date = Fri 15 Oct 2004 01:00:00 AM PDT (60.7 days from
now).
Features :=
Platform = Linux
Version
= 4.0
Tier
= Unused
Reserved
= 0
Mode
= TRAFFIC_DIRECTOR
Before Starting VCS Traffic Director
Before starting VCS Traffic Director, ensure that:
◆
The VCS configuration is “Read Only.”
◆
The VCS configuration is not opened for making configuration changes. This applies if you
are starting VCS Traffic Director using tdctl -start or hagrp -online TDService
-sys sysname.
Ensure that the VCS configuration is “Read Only” by using:
/opt/VRTSvcs/bin/haclus -value ReadOnly
If the output indicates a value of 0, it implies that the VCS configuration has been opened for
making configuration updates, either inadvertently or on purpose. Before proceeding further,
ensure that any desired configuration updates to the VCS configuration are made, and close VCS
configuration by using:
/opt/VRTSvcs/bin/haconf -dump -makero
5
Known Issues
Known Issues
The following paragraphs describe known problems for VCS Traffic Director 4.0 and approaches
to solving them.
Unexpected Behavior of VCS Traffic Director Web Servers
When you connect to a site and the page is not available, the local web browser sets the URL to that
of the "ServerName" /. This makes it necessary to have the web server use the VIP name for
the ServerName attribute. This behavior was reported for Netscape connecting to Apache 1.3.x.
Workaround: Web server should use VIP name for ServerName attribute.
FTP in PASV Mode with Filter Type as “port” Reveals Back-end
Server IPs
If FTP is initiated to port 21 with filter type configured as “port” instead of as “ftp”, then back-end
server IP addresses might be revealed.
Workaround: Use the correct filter type for the FTP port. Set filter type to “ftp”.
Nodes May Enter READYLOCAL State when Disconnecting
Under Load
Under extremely heavy load, both VCS Traffic Director nodes may transition into READYLOCAL
state.
Workaround: For Active/Active Configurations, issue the following commands on the less critical
node:
tdctl -stop
tdctl -start
For Active/Passive configurations, enter the above commands on the passive node.
6
VCS Traffic Director Release Notes
Known Issues
Server State in Web Console is Inaccurate If pingcheck is Off
The state of back-end servers is considered to be ONLINE if the pingcheck attribute is set to “no.”
If a back-end server is offline and pingcheck is turned off, the Web Console does not update the
back-end server status.
Workaround: If pingcheck is turned off, check back-end server status using the command line.
Update Mode Does Not Persist When the User Changes Pages
If the user changes the Update mode to AutoRefresh and then navigates to a different page, the
mode in the Web Console automatically reverts to NotifyOnly.
Closing the Traffic Monitor Window May Freeze the Browser
Workaround: Terminate and restart the browser.
Traffic Summary Save Option Limitation
For both the Traffic Summary and Traffic Summary Graph, the Save option is limited if the user
moves the ClusterService service group to a different system. Settings for charts and graphs
that have previously been saved one system will not be available on another system.
Workaround: To use previously saved settings, the following files must be copied to the system
where the ClusterService service group is currently online:
◆
For Traffic Summary: /var/VRTStd/loginname/dachart
◆
For Traffic Summary Graph: webbase/user/loginname/chart.ser.gz
On Red Hat Systems, Manual Pages Display Garbled Output
Manual pages invoked on Red Hat systems display garbled characters. To correct the problem, set
the LC_ALL environment variable:
LC_ALL=C
See incident 82099 on the Red Hat support Website for more information.
7
Software Limitations
Node Poweroff and Domain Failover
A VCS Traffic Director Domain does not failover if the node where Domain is online has only one
surviving heartbeat link and the node experiences an outage.
▼
To bring the Domain online
1. After the node with the outage rejoins the cluster, enter:
tdconfig -cmd "get domain name=domain_name"
where <domain_name> is the domain that was online on the node where the outage occurred.
2. If the output indicates the Domain is online on the node where outage occurred:
a. Enter:
tdconfig -cmd "shutdown domain name=domain_name sys=outage_sys"
where outage_sys is the node where the outage occurred and the Domain is shown as
online.
b. Enter:
tdconfig -cmd "online domain name=domain_name sys=tdsys"
where tdsys is the node where the Domain must be brought online.
Software Limitations
The following limitations apply to VCS Traffic Director 4.0.
Web Console Requires Cluster Administrator Privileges
The Traffic Director Daemon uses VCS privileges to authenticate user login. If the user is not a
VCS Cluster Administrator, the login is rejected.
Web Console Connects to One Traffic Monitor at a Time
The VCS Traffic Director Web Console connects to one Traffic Director Daemon at a time. If your
Web Console is connected to the Traffic Director Daemon on host A, but the domain is online on
host B, the Traffic Monitor charts for that domain will not report any data.
8
VCS Traffic Director Release Notes
Software Limitations
Multiple URL Requests on One Connection Go to Same Server
VCS Traffic Director supports both HTTP 1.0 and HTTP 1.1. When a port’s filter type is "url",
load balancing is based on the URL pattern. However, when HTTP KeepAlive is turned on, the
client can send multiple URL requests on the same TCP connection. VCS Traffic Director version
4.0 does not keep track of multiple URL requests on the same TCP connection. This results in all
the requests being forwarded to the selected server based on the first URL request. The same
limitation applies for HTTP 1.1 pipelined requests.
ClusterServiceGroup in a multiple node installation of VCS Traffic Director (installation of
VCS Traffic Director in a more than two node cluster) may only be ONLINE on one of the two
designated VCS Traffic Director nodes.
Use of Access Control List (ACL) with Source Network
Address Translation (SNAT)
If an Access Control List (ACL) with an action of SNAT is being used on a port (service) to load
balance http traffic or to load balance short lived client connections (whose total life span is less
than 1 second) then the following is strictly required:
The sync attribute for the port to which such short lived connections are made should be set to no.
9
Documentation
Documentation
Documentation for VCS Traffic Director is available as Adobe Portable Document Format
(PDF) files on the product CD. Documentation is also available in HTML format on the
software disc included with your software purchase. The VERITAS product installer offers
the option to install the product documentation and manual pages during installation.
VCS Traffic Director Documentation Set
Manual Title
Filename
VERITAS Cluster Server Traffic Director
/opt/VRTS/docs
VERITAS Cluster Server Traffic Director User’s Guide
td_ug.pdf
VERITAS Cluster Server Traffic Director Installation Guide
td_ig.pdf
VERITAS Cluster Server Traffic Director Release Notes
td_notes.pdf
VERITAS Cluster Server
/opt/VRTS/docs
VERITAS Cluster Server User’s Guide
vcs_ug.pdf
VERITAS Cluster Server Installation Guide
vcs_ig.pdf
VERITAS Cluster Server Agent Developer’s Guide
vcs_adg.pdf
VERITAS Cluster Server Bundled Agents Reference Guide
vcs_barg.pdf
VERITAS Cluster Server Release Notes
vcs_notes.pdf
VERITAS recommends copying the installation guide and release notes from software
discs containing the products to the /opt/VRTS/docs directory so that they are
available on your system for reference.
10
VCS Traffic Director Release Notes
Documentation
Documentation Online
Visit the website for VERITAS Software Technical Services.
http://support.veritas.com
Navigate via the Online Documentation link and select the VCS Traffic Director documentation.
Hard Copy Documentation
Copies of VERITAS software guides are available for purchase through the VERITAS DocStoreTM
at http://www.veritas.com/docstore.
Manual Pages
The manual pages for VRTStd, VRTSllt, VRTSgab, and VRTSvcs are installed in
/opt/VRTS/man. Set the MANPATH environment variable so the man(1) command can point to
the VCS manual pages.
For Bourne or Korn shell (sh or ksh), type:
# MANPATH=$MANPATH:/opt/VRTS/man
# export MANPATH
# LC_ALL = C export LC_ALL
For C shell (csh or tcsh), type:
# setenv MANPATH ${MANPATH}:/opt/VRTS/man
# setenv LC_ALL C
For more information, refer to the man(1) manual page.
11
Conventions
Conventions
Convention
Usage
Example
monospace
Used for path names, commands, output, directory and
file names, functions, and parameters.
Read tunables from the
/etc/vx/tunefstab file.
See the ls(1) manual page for more information.
monospace
(bold)
Indicates user input.
# ls pubs
italic
Identifies book titles, new
terms, emphasized text, and
variables replaced with a
name or value.
See the User’s Guide for details.
Depicts GUI objects, such as
fields, list boxes, menu selections, etc. Also depicts GUI
commands.
Enter your password in the Password
field.
blue text
Indicates hypertext links.
See “Getting Help” on page 13.
#
Unix superuser prompt (all
shells).
# cp /pubs/4.0/user_book
/release_mgnt/4.0/archive
C:\>
Windows user prompt.
C:\> copy \pubs\4.0\user_book
bold
C:\> dir pubs
The variable system_name indicates the
system on which to enter the command.
Press Return.
c:\release_mgnt\4.0\archive
$
12
Oracle user prompt
$ <command>
VCS Traffic Director Release Notes
Getting Help
Getting Help
VERITAS offers you a variety of support options.
Accessing the VERITAS Support Web Site
The VERITAS Support Web site allows you to:
◆
contact the VERITAS Support staff and post questions to them
◆
get the latest patches, upgrades, and utilities
◆
view the VCS TD Frequently Asked Questions (FAQ) page
◆
search the knowledge base for answers to technical support questions
◆
receive automatic notice of product updates
◆
find out about VCS TD training
◆
read current white papers related to VCS TD
The address for the VERITAS Support Web site is:
http://support.veritas.com
Subscribing to VERITAS Email Notification Service
Subscribe to the VERITAS Email notification service to be informed of software alerts,
newly published documentation, Beta programs, and other services.
Go to http://support.veritas.com. Select a product and click “E-mail Notifications” on the
right side of the page. Your customer profile ensures you receive the latest VERITAS
technical information pertaining to your specific interests.
Accessing VERITAS Telephone and Fax Support
Telephone support for VCS TD is only available with a valid support contract. To contact
VERITAS for technical support, dial the appropriate phone number listed on the Support
Guide included in the product box and have your product license information ready for
quick navigation to the proper support group.
The address for the VERITAS telephone support directory is:
http://support.veritas.com/phone
13
Getting Help
Contacting VERITAS Licensing
For license information call 1-800-634-4747 option 3, fax 1-650-527-0952, or e-mail
amercustomercare@veritas.com.
Using VRTSexplorer
The VRTSexplorer program can help VERITAS Technical Support engineers diagnose
technical problems associated with VERITAS products. You can download it from the VERITAS
FTP site. For more information, consult the README file in the VRTSexplorer directory on
the VERITAS CD.
▼
To install VRTSexplorer from the VERITAS CD
1. Log in as root.
2. Place the VERITAS CD into a CD-ROM drive connected to your system. If the CD does not
get automatically mounted, then enter:
# mount -o ro /dev/cdrom /mnt/cdrom
3. Move to the /mnt/cdrom/support directory and install the VRTSspt package:
# cd /mnt/cdrom/support
Depending on your machine type, enter:
# rpm -i ./VRTSspt-*.i386.rpm
or
# rpm -i ./VRTSspt-*.s390.rpm
The program is installed in the /opt/VRTSspt directory.
14
VCS Traffic Director Release Notes
Getting Help
Downloading VRTSexplorer from the VERITAS FTP Site
You can download vxexplore.tar.Z or VRTSspt-linux.tar.Z.
▼
To download vxexplorer.tar.Z
1. Use a web browser or the ftp program to download the VRTSexplorer program from the
following URL:
ftp://ftp.veritas.com/pub/support/vxexplore.tar.Z
Save the file to the /opt/VRTSspt directory. Create the directory /opt/VRTSspt if it
does not exist.
2. Log in as root on the affected system, and use the following commands to extract the contents
of the downloaded file to the directory /opt/VRTSspt:
# cd /opt/VRTSspt
# zcat vxexplore.tar.Z | tar xvf -
▼
To download VRTSspt-linux.tar.Z
1. Use a web browser or the ftp program to download the VRTSexplorer program from the
following URL:
ftp://ftp.veritas.com/pub/support/VRTSspt-linux.tar.Z
Save the file to the /opt/VRTSspt directory. Create the directory /opt/VRTSspt if it
does not exist.
2. Log in as root on the affected system, and use the following commands to extract the contents
of the downloaded file to the directory /opt/VRTSspt:
# cd /opt/VRTSspt
# zcat VRTSspt-linux.tar.Z | tar xvf # cd VRTSspt-linux
3. Depending on your machine type, enter:
# rpm -i ./VRTSspt-*.i386.rpm
or
# rpm -i ./VRTSspt-*.s390.rpm
15
Getting Help
▼
To run the VRTSexplorer program
1. Run the VRTSexplorer program from the VRTSexplorer directory by entering the
following command:
# /opt/VRTSspt/VRTSexplorer/VRTSexplorer
VRTSexplorer prompts you for a destination directory for the information that it collects.
2. Press Return to accept the default directory /tmp, or enter a path name of your own choice.
VRTSexplorer writes information to a compressed tar file named
VRTSexplorer_casenumber_hostname.tar.Z in the specified directory.
3. Use the file upload facility of your web browser, or the ftp program, to transfer the
VRTSexplorer output file to the VERITAS Technical Support anonymous FTP site:
ftp://ftp.veritas.com/incoming
4. When you call VERITAS Technical Support, provide the name of the file you transferred to the
FTP site.
Alternatively, if you have already been assigned a call ID number by VERITAS Technical
Support, email support@veritas.com and include your case ID number in the subject line.
▼
To remove the VRTSexplorer program
To remove the VRTSexplorer program type:
# rpm -e VRTSspt
16
VCS Traffic Director Release Notes
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