CentOS-7 (2003) Release Notes

Last updated: April 27, 2020

1. Translations

Translations of these release notes are available for the following languages:

2. Introduction

Hello and welcome to the ninth CentOS-7 release. The CentOS Linux distribution is a stable, predictable, manageable and reproducible platform derived from the sources of Red Hat Enterprise Linux (RHEL)1. You can read our official product announcement for this release here.

CentOS conforms fully with Red Hat's redistribution policy and aims to have full functional compatibility with the upstream product. CentOS mainly changes packages to remove Red Hat's branding and artwork.

We have decided not to follow Red Hat's usage of Installation Roles. In CentOS Linux all content from every distribution 'channel' is made available to the user at time of installation.

The CentOS Project does not provide any verification, certification, or software assurance with respect to security for CentOS Linux. The Security Profiles provided in the CentOS Linux installers are a conversion of the ones included in RHEL Source Code. If certified / verified software that has guaranteed assurance is what you are looking for, then you likely do not want to use CentOS Linux. See this link if you plan to use Security Profiles.

3. Install Media

Various installation images are available for installing CentOS. Which image you need to download depends on your installation environment. All of these images can either be burned on a DVD or dd’ed to an USB memory stick. In 7.8.2003 you will require a DVD-DL dual layer disc to write the DVD iso image as it is just too large to fit on a single layer disc.

If you are unsure which image to use, pick the DVD image. It allows selecting which components you want to install and contains all packages that can be selected from the GUI installer. The 'Everything' image is more than twice the size of the ordinary DVD and is not required for most common installs - it is intended for use by sysadmins who want to run their own local mirror. Using the Everything image does not give you more options for package selection within the installer.

Live media images are also available, both for Gnome and KDE desktop environments. These allow you to test out CentOS by booting from the DVD or USB stick. You can also install CentOS to your hard disk from the live media images, but please note that what gets installed on your hard disk is exactly the same as you see when using the live media. For more flexibility in selecting which packages you want to have installed, please use the DVD image.

The netinstall image can be used for doing installs over network. After booting the computer with the netinstall image, the installer will ask from where it should fetch the packages to be installed.

The everything image contains all the packages that are available for CentOS-7, including those that are not directly installable from the installer. If you want to install those other packages, you must mount the install media on your installed system after the installation, and copy or install the packages from there. For most users installing from the DVD image and then installing the other packages with ”yum install <packagename>” instead is probably easier.

At least 1280 MB RAM is required to install and use CentOS-7 (1810). When using the Live ISOs for install, 1280 MB RAM produces very slow results and even some install failures. At least 1536 MB RAM is recommended for LiveGNOME or LiveKDE installs. See Bug 8353.

4. Verifying Downloaded Installation Images

Before copying the image to your preferred installation media you should check the sha256sum of the downloaded installation images.

087a5743dc6fd6706d9b961b8147423ddc029451b938364c760d75440eb7be14  CentOS-7-x86_64-DVD-2003.iso

4120aff542c2f9a30bcf90d4d79e39511e5d9eabdf202566a94ff24ea7f0974c  CentOS-7-x86_64-Everything-2003.iso

659691c28a0e672558b003d223f83938f254b39875ee7559d1a4a14c79173193  CentOS-7-x86_64-Minimal-2003.iso

101bc813d2af9ccf534d112cbe8670e6d900425b297d1a4d2529c5ad5f226372  CentOS-7-x86_64-NetInstall-2003.iso

3febddab1498f940e3127f2f5e1056d6fef57fcd559d5b70ff1bfa55a444f176  CentOS-7-x86_64-LiveGNOME-2003.iso

92be566a5b1d2aa62acf2e4ab01ba91420e7170cdb21e2e190dd1dafcb6a8c94  CentOS-7-x86_64-LiveKDE-2003.iso

5. Major Changes

6. Deprecated Features

Please see the list of deprecated functionality to help you plan forward with future deployments.

7. Known Issues

A list of known upstream issues can be found here. Given that we build from the same sources, many if not all of those issues will likely also apply to CentOS Linux.

Some security profiles enable a global repo_gpgcheck option in /etc/yum.conf to cryptographically verify the repository metadata. While this works for CentOS repositories, some third party repositories (such as EPEL) do not support GPG signed metadata. If repo_gpgcheck is enabled yum will try to download the signed metadata file repomd.xml.asc. If the file does not exist, yum will output an error message and exit. You may need to either remove repo_gpgcheck from /etc/yum.conf or set repo_gpgcheck=0 for each individual repository that does not support GPG signed metadata.

Red Hat have updated the ImageMagick package from 6.7.8 to 6.9.10 and some things in third party yum repos that build against it will need to be rebuilt to cater for this. Known packages affected by this change are: transcode from nux-dextop and the Epson supplied scanner utility imagescan. You will need to wait for the thos packages to be updated by their maintainers before you can update or remove them first.

If you use KDE and your default shell is csh or tcsh, you will see the error "if: Expression Syntax". This is a known bug. See RHBZ #1738491 for details and a fix.

In certain configurations selecting the "Install CentOS 7 in basic graphics mode" option may use text mode instead of basic graphics mode.

The samba 4.9 upgrade has been reported to cause the service to fail to start with an error about a missing BUILTIN\\Guests group or 'create_local_token failed: NT_STATUS_ACCESS_DENIED'. The fix for this is to run net -s /dev/null groupmap add sid=S-1-5-32-546 unixgroup=nobody type=builtin as per this Fedora Bugzilla entry https://bugzilla.redhat.com/show_bug.cgi?id=1648399 which is worth a read for some other config changes too.

The iptables upgrade (iptables-1.4.21-33.el7.x86_64) has been reported to cause iptables-restore failure when a '-' and a 't' are used in the comment field. This is a known bug. See https://bugzilla.redhat.com/show_bug.cgi?id=1749700 for details.

If you use DRBD, you need to update the DRBD packages from ELRepo to the version for the new 7.8 kernel series. If you use the old packages, the symptom of them being broken is that the resources will not start and you will see messages like "kernel: drbd: error sending genl reply" in your logs.

8. Fixed Issues

9. Packages and Applications

9.1. Packages modified by CentOS

9.2. Packages removed from CentOS that are included upstream

9.3. Packages added by CentOS that are not included upstream

9.4. Packages released as 7.7.1908 updates with older packages on the 7.8.2003 install media

10. Sources

All CentOS-7 sources are hosted at git.centos.org. All code released into the distribution originated from git.centos.org.

Source RPMs will also be published once the release is done, in the usual location at http://vault.centos.org/centos/7/

From a CentOS machine you can easily retrieve sources using the yumdownloader --source <packagename> command.

11. How to help and get help

As a CentOS user there are various ways you can help out with the CentOS community. Take a look at our Contribute page for further information on how to get involved.

11.1. Special Interest Groups

CentOS consists of different Special Interest Groups (SIGs) that bring together people with similar interests. The following SIGs already exist (among others):

And we encourage people to join any of these SIGs or start up a new SIG, e.g.

11.2. Mailing Lists and Forums

Another way you can help others in the community is by actively helping and resolving problems that users come up against in the mailing lists and the forums.

11.3. Wiki and Website

Even as an inexperienced CentOS user we can use your help. Because we like to know what problems you encountered, if you had problems finding specific information, how you would improve documentation so it becomes more accessible. This kind of feedback is as valuable to others as it would have been to you so your involvement is required to make CentOS better.

So if you want to help out and improve our documentation and Wiki, register on the Wiki or subscribe to the centos-docs mailing list.

11.4. IRC Presence

The CentOS project maintains a presence on the freenode IRC network as an additional venue for community support and interaction. Please see our IRC wiki article for more information.

12. Further Reading

The following websites contain large amounts of information to help people with their CentOS systems:

13. Thanks

We thank everyone involved for helping us produce this product and would like to specifically acknowledge the extra effort made by the QA Team. Without them working lots and lots of hours in evenings, nights, weekends and holidays, we couldn't have released this Release in the time we did. A special thanks also goes to the CentOS-community. A more complete list of the contributors to this release can be found at /usr/share/doc/centos-release/Contributors of your new CentOS-7 installation.

Copyright (C) 2020 The CentOS Project

Manuals/ReleaseNotes/CentOS7.2003 (last edited 2020-06-01 21:42:53 by TrevorHemsley)