CDN Cloudflare how to set and preserve the real IP of the client without modifying application code on Apache

Your frontend CDN (eg. Cloudflare or even your own load balancer/proxy) must be sending the X-Forwarded-For and you must be running Apache on the backend. This solves the problem where your logs and services will only see the proxy/CDN IP and not the real client IP. mod_rpaf will fix all of this This solution transparently sets the real IP of the client for Apache and any services that rely on........

CentOS 7 fix Could not retrieve mirrorlist http://mirrorlist.centos.org/?release=7&arch=x86_64&repo=os&infra=container error was 14: curl#6 -

yum update Loaded plugins: fastestmirror, ovl Determining fastest mirrors Could not retrieve mirrorlist http://mirrorlist.centos.org/?release=7&arch=x86_64&repo=os&infra=container error was 14: curl#6 - "Could not resolve host: mirrorlist.centos.org; Unknown error" One of the configured repositories failed (Unknown), and yum doesn't have enough cached data to continue. At this point the onl........

How to set Linux Ubuntu Redhat Debian Command Line http https socks proxy for yum apt

Just export these variables: export http_proxy="socks5://127.0.0.1:1234" export https_proxy="socks5://127.0.0.1:1234" The above example uses a socks 5 proxy at localhost and port 1234. This is a great way to improve performance of some activities for things like package installation, especially if your routing is not ideal to the repos.........

configure.ac:75: error: possibly undefined macro: AC_PROG_LIBTOOL If this token and others are legitimate, please use m4_pattern_allow. See the Autoconf documentation. solution

configure.ac:75: error: possibly undefined macro: AC_PROG_LIBTOOL If this token and others are legitimate, please use m4_pattern_allow. See the Autoconf documentation. autoreconf: /usr/bin/autoconf failed with exit status: 1 make: *** [/software/pixman/configure] Error 1 make: *** Deleting file `/software/pixman/configure' yum install libtool........

Can't exec "aclocal": No such file or directory at /usr/share/autoconf/Autom4te/FileUtils.pm line 326. autoreconf: failed to run aclocal: No such file or directory solution

autoreconf: Entering directory `.' autoreconf: configure.ac: not using Gettext autoreconf: running: aclocal --output=aclocal.m4t Can't exec "aclocal": No such file or directory at /usr/share/autoconf/Autom4te/FileUtils.pm line 326. autoreconf: failed to run aclocal: No such file or directory make: *** [/software/pixman/configure] Error 1 Just install automake: yum install automake........

/bin/sh: autoreconf: command not found solution

This means the autoconf package is not installed, so we'll install it: /bin/sh: autoreconf: command not found yum install autoconf On Debian apt install autoconf........

glib-2.0 required to compile QEMU solution

./configure glib-2.0 required to compile QEMU yum install glib2 glib2-devel or on Debian/Ubuntu based: apt install libglib2 libglib2-dev........

CentOS 7 / 8 cannot boot with with mdadm RAID array solution

This article about migrating to a CentOS 7 /8 RAID mdadm array has a lot of info but I wanted to focus specifically on what newer versions of CentOS 7 require to boot mdadm and what changes are necessary on CentOS 7.8+ CentOS 7 / 8 mdadm RAID booting requirements This assumes you are chrooting into an existing install or using it to get a new deployment ready. However, these steps can........

Error: Failed to download metadata for repo 'appstream': Cannot prepare internal mirrorlist: No URLs in mirrorlist Solution for Centos8 yum package install error

Are you getting this error in CentOS 8 when trying to use yum to install a package? Error: Failed to download metadata for repo 'appstream': Cannot prepare internal mirrorlist: No URLs in mirrorlist What we need to do is not use the automatic mirror list and manually set the base URL Solution sed -i 's/mirrorlist/#mirrorlist/g' /etc/yum.repos.d/CentOS* sed -i 's%#baseurl=http://mirror.centos.org%baseurl=........

CentOS 6 EOL yum repo won't work Error: Cannot find a valid baseurl for repo: base Solution

yum update Loaded plugins: fastestmirror Setting up Install Process Determining fastest mirrors YumRepo Error: All mirror URLs are not using ftp, http[s] or file. Eg. Invalid release/repo/arch combination/ removing mirrorlist with no valid mirrors: /var/cache/yum/x86_64/6/base/mirrorlist.txt Error: Cannot find a valid baseurl for repo: base You have mail in /var/spool/mail/root ........

CentOS 7 8 yum error Trying other mirror. To address this issue please refer to the below wiki article

The below appears at first to be a bad mirror DNS error, but if you've ruled that out you just need to clear your broken yum cache and things will be good. yum update Loaded plugins: fastestmirror Loading mirror speeds from cached hostfile * base: centos.01link.hk * extras: centos.01link.hk * updates: centos.01link.hk http://mirror.worria.com/centos/7.8.2003/os/x86_64/repodata/repomd.xml: [Errno 14] HTTP Error 404 - Not........

http://vault.centos.org/5.9/os/i386/repodata/filelists.xml.gz: [Errno -1] Metadata file does not match checksum solution

http://vault.centos.org/5.9/os/i386/repodata/filelists.xml.gz: [Errno -1] Metadata file does not match checksum yum clean all yum makecache yum update........

CentOS 6 impossible to compile a newer libguestfs

yum -y install gcc make gperf genisoimage flex bison ncurses ncurses-devel pcre-devel augeas-devel augeas readline-devel checking for cpio... cpio checking for gperf... no configure: error: gperf must be installed configure: error: Package requirements (augeas >= 1.2.0) were not met: Requested 'augeas >= 1.2.0' but version of augeas is 1.0.0 yum remove augeas augeas-libs augeas-devel wget http://downl........

Remove cloud-init in your VM

Unless you are using OpenStack, AWS etc then cloud-init is just some bloat that slows down the booting of your VMand can actually halt it from booting if it doesn't have a proper working IP (not good!). #remove cloud init! Debian based Ubuntu / Mint sudo apt remove cloud-init RHEL / CentOS based yum remove cloud-init ........

How To Install NextCloud on Centos 7 and Centos 8

yum -y install wget unzip wget https://download.nextcloud.com/server/releases/nextcloud-18.0.2.zip unzip nextcloud-18.0.2.zip yum -y install php php-mysqlnd php-json php-zip php-dom php-xml php-libxml php-mbstring php-gd mysql mysql-server Last metadata expiration check: 0:58:02 ago on Fri 13 Mar 2020 02:12:49 PM EDT. Dependencies resolved. ===================================================================........

How To Install OpenProject on Centos 7 Step-by-Step Guide

There are a few caveats that may not be obvious to everyone so I am going to cover them here but keep this in mind before starting. Before starting install epel or you will be missing tesseract: yum -y install epel-release #1) When you specify your SSL certificate with a full path, it really needs to exist where you tell it to (including the default location of /etc/ssl/certs and /etc/ssl/c........

named bind errors - DNSKEY: unable to find a DNSKEY which verifies the DNSKEY RRset and also matches a trusted key for '.'

Mar 22 13:46:14 box named[31767]: validating @0x7f51bc001550: . DNSKEY: unable to find a DNSKEY which verifies the DNSKEY RRset and also matches a trusted key for '.' Mar 22 13:46:14 box named[31767]: validating @0x7f51bc001550: . DNSKEY: please check the 'trusted-keys' for '.' in named.conf. Mar 22 13:46:14 box named[31767]: error (broken trust chain) resolving './NS/IN': 192.36.148.17#53 One possibility is sometimes that your time is ou........

CentOS 8 how to convert to a bootable mdadm RAID software array

The cool thing here is that we only need 1 drive to make a RAID 10 or RAID 1 array, we just tell the Linux mdadm utility that the other drive is "missing" and we can then add our original drive to the array after booting into our new RAID array. Step#1 Install tools we need yum -y install mdadm rsync Step #2 Create your partitions on the drive that will be our RAID array Here I assume it is /dev........

python ModuleNotFoundError: No module named 'bs4' even though you have the module

In this case I am executing using "python3" but what you find in cases like this can be surprising. The most common issues are that someone has a module for python 2 "pip" and doesn't realize they need "pip3" to install it for python3, but this is not one of those cases. ModuleNotFoundError: No module named 'bs4' OKmaybe we didn't install it for python3? [........

Centos 7 How to install Mysql/Mariadb

yum -y install mariadb-server systemctl start mariadb mysql_secure_installation Now we need to secure our install and set the MariaDB root password: The lines you need to act on are marked in bold shown with the answer you need. mysql_secure_installation NOTE: RUNNING ALL PARTS OF THIS SCRIPT IS RECOMMENDED FOR ALL MariaDB SER........

PHP 7.2, Apache and Centos 7 How To Install

yum install centos-release-scl yum install rh-php72 rh-php72-php rh-php72-php-mysqlnd Symlink PHP binary: ln -s /opt/rh/rh-php72/root/usr/bin/php /usr/bin/php Symlink Apache and PHP module config: ln -s /opt/rh/httpd24/root/etc/httpd/conf.d/rh-php72-php.conf /etc/httpd/conf.d/ ln -s /opt/rh/httpd24/root/etc/httpd/conf.modules.d/15-rh-php........

Centos 7 how to save iptables rules like Centos 6

yum install iptables-services systemctl enable iptables service iptables save iptables: Saving firewall rules to /etc/sysconfig/iptables:[ OK ]........

How to install and setup LXC Containers (OpenVZ alternative) on Centos 6 / 7

If you don't aleady have it, you'll need EPEL Install LXC yum -y install lxc lxc-templates Loaded plugins: fastestmirror Setting up Install Process Loading mirror speeds from cached hostfile * base: mirror.it.ubc.ca * epel: mirrors.kernel.org * extras: mirror.it.ubc.ca * updates:........

iSCSI on Centos 7 Configuration and Setup Guide for Initiator and Target

initiator = client target = server These are the first concepts you should understand which is that in iscsi essentially the "initiator" is the client and the "target" is the server. iSCSI is derived from the old fashioned SCSI that us oldtimers grew to love. The "i" stands for Internet and the SCSI stands for "Small Computers Systems Interface" (SCSI). iSCSI Target (Server)Setup targetcli is the pac........

Centos 7 PHP MySQL Not Working Solution

PHP Warning: PHP Startup: Unable to load dynamic library '/usr/lib64/php/modules/pdo_mysql.so' - /usr/lib64/php/modules/pdo_mysql.so: symbol mysql_options, version libmysqlclient_18 not defined in file libmysqlclient.so.18 with link time reference in Unknown on line 0 #not sure what is wrong with php-mysql but I removed it and installed mysqlnd yum -y remove php-mysql yum -y install php-mysqlnd........

MySQL Using mytop Debug Source of High IO and Slow Performance

mytop is one of my favorite tools and it is fairly simple aside from a few caveats and issues that persist to this day. To install it on Centos: yum -y install centos Configure ~/.mytop vi ~/.mytop user=root host=localhost db=test #port=3306 socket=/var/lib/mysql/mysql.sock header=1 color=1 Try runni........

Centos 7 python34 how to install the gi library

Getting an error about gi missing when running a .py python script? Just install EPEL and install the python3-gobject package: yum install python34-gobject........

Centos 7 - Convert Minimal to Graphical GUI GNOME or KDE Desktop

Did you just install the minimal version by accident or want to install the GUI? No need to reinstall just tell yum to do the work for you! You could actually have both installed and choose one as your preference on demand (although many people prefer GNOME's simplicity). Step 1.) Install Gnome and/or KDE. To install the GNOME Desktop on Centos 7: yum -y groups install "GNOME Desktop" To........

error while loading shared libraries: libasound.so.2: cannot open shared object file: No such file or directory

./tronwatch: error while loading shared libraries: libasound.so.2: cannot open shared object file: No such file or directory [root@testing linux-unpacked-1.0.7]# Solution: yum -y install alsa-lib-devel........

Linux Centos 7 HowTo Install Yarn

https://yarnpkg.com/lang/en/docs/install/#centos-stable curl --silent --location https://dl.yarnpkg.com/rpm/yarn.repo | tee /etc/yum.repos.d/yarn.repo If you need node.js: curl --silent --location https://rpm.nodesource.com/setup_6.x | bash - yum install nodejs yarn........

Centos 7 - How To Install NFS and Mount Remotely

Server Side Config 1.) First install nfs-utils yum -y install nfs-utils 2.) Configure nfs share Create a directory for your NFS share mkdir /datastore Create your NFS share in /etc/exports echo "/datastore 10.220.101.0/24(rw,sync,no_root_squash)" >> /etc/exports systemctl restart nfs........

NFS Share Won't Mount Solution - mount: wrong fs type, bad option, bad superblock on 10.10.2.20:/tmp/nfsmount

nfs mount failed: mount 10.10.2.20:/tmp/nfsmount /mnt/nfs/ mount: wrong fs type, bad option, bad superblock on 10.10.2.20:/tmp/nfsmount, missing codepage or helper program, or other error (for several filesystems (e.g. nfs, cifs) you might need a /sbin/mount. helper program) ........

curl: (35) Unknown SSL protocol error in connection Solution Centos

curl: (35) Unknown SSL protocol error in connection The main solution is to update curl and nss. If you are having an issue with curl through Apache/PHPyou will need to restart PHPafter. It's important to remember that this error could mean a lot of things but most often it simply means that curl and openssl may be outdated and only allow newer secure ways of connecting to SSL. In general here is how you would fix it in most c........

PHP Warning: Cannot load module 'XCache' because conflicting module 'apc' is already loaded in Unknown on line 0

PHP Warning: Cannot load module 'XCache' because conflicting module 'apc' is already loaded in Unknown on line 0 Solution: yum remove php-pecl-apc-*........

Unable to load dynamic library '/usr/lib64/php/modules/module.so' - /usr/lib64/php/modules/module.so: cannot open shared object file: No such file or directory in Unknown on line 0

Getting this error on Centos 6 with PHP 5.3 when just running "php -v" PHP Warning: PHP Startup: Unable to load dynamic library '/usr/lib64/php/modules/module.so' - /usr/lib64/php/modules/module.so: cannot open shared object file: No such file or directory in Unknown on line 0 PHP Warning: Cannot load module 'XCache' because conflicting module 'apc' is already loaded in Unknown on line 0 Solution:........

GCC 5 on Centos 6 - How To Install

Install requirements: yum -y install gmp-devel mpfr-devel libmpc-devel glibc-devel glibc-devel.i686 zip unzip jar Download, untar, configure, compile and install GCC http://mirrors.kernel.org/gnu/gcc/gcc-5.5.0/gcc-5.5.0.tar.gz tar -zxvf gcc-5.5.0.tar.gz cd gcc-5.5.0 ./configure make make install Now you need to cleanup th........

Install Windows From a Linux TFTP Server instead of using WDS Solution

yum -y install samba vi /etc/samba/smb.conf https://www.kernel.org/pub/linux/utils/boot/syslinux/syslinux-6.03.zip mkdir syslinux;cd syslinux;unzip syslinux-6.03.zip mkdir -p /tftpboot/libs/ cp bios/com32/modules/linux.c32 /tftpboot/libs/ cp bios/com32/libutil/libutil.c32 /tftpboot/libs/ cp bios/com32/lib/libcom32.c32 /tftpboot/libs/ #add lib path echo "PATH libs" >> /tftpboot/pxeli........

cannot mount kvm ntfs image

guestmount -a kvmuserscra.img -m /dev/sda1 mount libguestfs: error: mount_options: /dev/sda1 on / (options: ''): mount: unknown filesystem type 'ntfs' guestmount: '/dev/sda1' could not be mounted. guestmount: Did you mean to mount one of these filesystems? guestmount: /dev/sda1 (ntfs) guestmount: /dev/sda2 (ntfs) yum -y install ntfs-3g still........

yum how to install old obsolete packages

This is important as unfortunately Centos may designate a package obsolete and the replacement breaks everything (eg. you have a config file and the new replacement is not at all compatible with it and it breaks your application). This is where disabling obsoletes comes into play, it can be done from yum but it doesn't work at the time I find. yum --setopt=obsoletes=0 install someapp However Ifind it still installs the new app and not the one you ask for........

M2Crypto.SSL.Checker.WrongHost: Peer certificate subjectAltName does not match host, expected fedora-archive.ip-connect.vn.ua, got DNS:mirror.ip-connect.vn.ua

You are using Centos 5 which is deprecated so nothing in yum will work until you follow this post to use the vault: http://realtechtalk.com/Centos_59_Working_Vault_Repo_file-1921-articles yum update Loaded plugins: fastestmirror Loading mirror speeds from cached hostfile * epel: fedora-archive.ip-connect.vn.ua Traceback........

Centos 5.9 Working Vault Repo file

Centos 5 is not supported running yum will produce an error like this: YumRepo Error: All mirror URLs are not using ftp, http[s] or file. Eg. Invalid release/ removing mirrorlist with no valid mirrors: /var/cache/yum/base/mirrorlist.txt Error: Cannot find a valid baseurl for repo: base Solution - Update this file CentOS-Base.repo # CentOS-Base.repo........

Migrate Centos 7 from Single HDD to mdadm RAID 10 array:

Done on Centos 7.3 very important as clearly based on older guides it was a lot easier and more simpler! Hint do not use grub2-install! If you have trouble booting after this check this CentOS mdadm RAID booting/fixing guide. One huge caveat if you are an oldschool user or sysadmin who has avoided UEFIbooting The nor........

Centos 7 Cudaminer Nvidia setup guide

I am using a GTX 1060 but replace the download for the driver with the correct/current version for your particular card by visiting: http://www.nvidia.com/Download/index.aspx?lang=en-us yum install automake curl openssl-devel libcurl-devel gcc gcc-c++ yum -y install kernel-devel-`uname -r` yum -y install unzip #the........

Transaction Check Error: file /usr/lib64/php/modules/fileinfo.so conflicts between attempted installs of php-pecl-fileinfo-1.0.4-2.el6.rf.x86_64 and php-common-5.3.3-49.el6.x86_64 solution

Transaction Check Error: file /usr/lib64/php/modules/fileinfo.so conflicts between attempted installs of php-pecl-fileinfo-1.0.4-2.el6.rf.x86_64 and php-common-5.3.3-49.el6.x86_64 solution you can't install php-pecl-fileinfo it seems to be incompatble with the php5.3 being installed: yum --exclude=php-pecl-fileinfo --skip-broken --disablerepo=epel install php-*........

Linux Mint Install Netboot PXE Guide Howto

*Update so this doesn't work it must be something to do with the path of nfs or something else but the installer fails with "Installer crashed" at the end whereas with the CD/USB it works. This assumes you've already installed and configured a separate PXE/DHCP server somewhere else and your /tftpboot directory is setup. This is for Linux Mint 18.1 but generally applies to most versions although you may have tro change things like "casper"........

Centos 7 Migration Guide from Centos 6

Centos 7 is no cakewalk, there are many fundamental features and basic utilities that are missing or even completely renamed or different! Another shocking thing is to check your NIC it is set by default to not turn on when booting! And by the way there is no more standard eth0 the NIC convention is now "enp0s3" vi /etc/sysconfig/network-scripts/ifcfg-enp0s3........

yum Packages skipped because of dependency problems:

Solution: yum -y install --skip-broken package-you-want-to-install Packages skipped because of dependency problems: php56w-mysql-5.6.30-1.w6.x86_64 from webtatic Error: Multilib version problems found. This often means that the root cause is something else and multilib version checking is just pointing out that there is........

Using a proxy with yum in Centos 6

Could not retrieve mirrorlist http://mirrorlist.centos.org/?release=6&arch=x86_64&repo=os error was 12: Timeout on http://mirrorlist.centos.org/?release=6&arch=x86_64&repo=os: (28, 'Operation too slow. Less than 1 bytes/sec transfered the last 30 seconds') Error: Cannot find a valid baseurl for repo: base You would think this should be fine and simple like using a proxy with most other software? However........

PYCURL ERROR 22 - The requested URL returned error: 404 Not Found Solution

# yum -y install qemu-kvm Loaded plugins: fastestmirror Setting up Install Process Loading mirror speeds from cached hostfile * base: mirror.lzu.edu.cn * elrepo: ftp.utexas.edu * epel: ftp.jaist.ac.jp * extras: mirrors.aliyun.com * openvz-kernel-rhel6: mirror.fdcservers.net * openvz-utils: mirror.fdcservers.net * updates: mirrors.nwsuaf.edu.cn Resolving Dependencies........

OpenVZ Error: Failed to load 2nd level quota solution

Syncing private Live migrating container... Syncing 2nd level quota 11000: invalid option -- F Usage: vzdqload quotaid [-c file] commands Loads user/group qouta information from stdin into quota file. -c file use given quota file Commands specify what user/group information to load: -G grace time -U disk limits........

Centos and obfsproxy install errors

pip install obfsproxy /usr/lib/python2.6/site-packages/pip/_vendor/requests/packages/urllib3/util/ssl_.py:90: InsecurePlatformWarning: A true SSLContext object is not available. This prevents urllib3 from configuring SSL appropriately and may cause certain SSL connections to fail. For more information, see https://urllib3.readthedocs.org/en/latest/security.html#insecureplatformwarning. InsecurePlatformWarning You are using pip version 7.1.0, however version 8.1.1 i........

There was a problem importing one of the Python modules required to run yum. The error leading to this problem was:

There was a problem importing one of the Python modules required to run yum. The error leading to this problem was: No module named yum Please install a package which provides this module, or verify that the module is installed correctly. It's possible that the above module doesn't match the current version of Python, which is: 2.7.9 (default, Apr 21 2016, 16:51:58) [GCC 4.4.7 20120313........

curl: (35) SSL connect error solution

curl -k https://somesite.org curl: (35) SSL connect error The site used to work until I got a new SSL cert Updating curl with (yum -y install curl) made it work again. ........

Error: database disk image is malformed - yum error solution and fix

I got this when running yum on a Centos 6 machine: Error: database disk image is malformed It was easily fixed with the following command: yum clean all........

Centos 6 how to guide convert LVM non-RAID into mdadm 1/10 RAID array live without reinstalling

Here is the scenario you or a client have a remote machine that was installed as a standard/default minimal Centos 6.x machine on a single disk with LVM for whatever reason. Often many people do not know how to install it to a RAID array so it is common to have this problem and why reinstall if you don't need to? In some cases on a remote system you can't easily reinstall without physical or KVM access. So in this case you add a second physical or disk or already ha........

openvz yum problem Centos 6.5 cannot find file on mirror:

#solution Edit /etc/yum.repos.d/openvz.repo For the first two entries comment out #mirrorlist and uncomment #baseurl and then it worked openvz yum problem Centos 6.5 cannot find file on mirror: yum update Loaded plugins: fastestmirror Determining fastest mirrors * openvz-kernel-rhel6: mirrors.ustc.edu.cn * openvz-utils: mirrors.ustc.edu.cn base ........

Centos/obfsproxy errors

I never did get it working, it is too bad as obfsproxy should really be an option and integrated into the OpenVPN client and server or something similar: yum -y install python-pip python-devel No package python-pip available. #install the EPEL repo python-pip install obfsproxy python-pip install obfsproxy -bash: python-pip: command not found pip install obfsproxy &........

OpenVZ Install Guide Again / Quick Setup

yum -y install wget wget -P /etc/yum.repos.d/ http://ftp.openvz.org/openvz.repo rpm --import http://ftp.openvz.org/RPM-GPG-Key-OpenVZ yum -y install vzkernel vzctl #enable ip_forward sed -i s/'net.ipv4.ip_forward = 0'/'net.ipv4.ip_forward = 1'/g /etc/sysctl.conf #all interfaces should not send redirects echo "net.ipv4.conf.default.send_redirects = 1" >> /etc/sysctl.conf echo "net.ipv4.co........

Centos yum mirror problem error "[Errno 14] PYCURL ERROR 22 - "The requested URL returned error: 404 Not Found""

[Errno 14] PYCURL ERROR 22 - "The requested URL returned error: 404 Not Found" The above happened when for some reason all the mirrors in my cache didn't have the files (some mirrors only keep the latest version of Centos). Itried to block them all but that didn't help because it seemed the mirrors were all hardcoded no matter what I tried. Here is how to fix it and reset your mirror list in Centos cd /var/cac........

yum how to blacklist and exclude mirrors

vi /etc/yum/pluginconf.d/fastestmirror.conf exclude=.hk,.cn You could also use specific domains but as you can see above we are blacklisting all Hong Kong and Chinese mirrors in this example.........

Centos OpenDKIM & Postfix Setup Guidel

#from epel repo yum -y install opendkim chkconfig opendkim on cd /etc/opendkim/keys opendkim-genkey -vd mail.server.com opendkim-genkey: generating private key opendkim-genkey: private key written to default.private opendkim-genkey: extracting public key opendkim-genkey: DNS TXT record written to default.txt ........

dir2slideshow Centos rpm requirements

yum -y install dvdauthor ffmpeg mjpegtools sox bc rpm -ivh dvd-slideshow-0.8.4-2.noarch.rpm Preparing... ########################################### [100%] 1:dvd-slideshow ########################################### [100%] /usr/bin/dir2slideshow: line 553: bc: command not f........

No package fuse-encfs available. yum

It looks like newer versions of Centos no longer have encfs so you have to compile it, only it does not work and fails so those wanting encfs should probably use any other OS which supports it better.........

Error: Cannot retrieve metalink for repository: epel. Please verify its path and try again

Error: Cannot retrieve metalink for repository: epel. Please verify its path and try again You have to upgrade the ca-certs for epel but need to disable it before that can happen. yum upgrade ca-certificates --disablerepo=epel........

Centos scp or sftp program missing solution/what rpm provides them

You need the "openssh-clients" package which contains sftp and scp. yum -y install openssh-clients........

mytop install errors

mytop-1.4-2.el5.rf.noarch from rpmforge has depsolving problems --> Missing Dependency: perl(DBI) is needed by package mytop-1.4-2.el5.rf.noarch (rpmforge) solution: #disabling excludes is required on CPanel type boxes which exclude most updates including perl-DBI yum --disableexcludes=main install perl-DBI mytop-1.4-2.el5.rf.noarch from rpmforge has depsolving problems --> Missing Dependency:........

Openvz Can't load ploop library: libploop.so: cannot open shared object file: No such file or directory

Can't load ploop library: libploop.so: cannot open shared object file: No such file or directory The above happens when you haven't installed the ploop tools: yum -y install ploop........

Howto Convert Xen Image to KVM

#count=10000 makes an image of 10000MB make sure your image is at least the same as your existing dd if=/dev/zero of=yourimage.img bs=1M count=10000 # losetup -fv newimage.raw # fdisk -cu /dev/loop0 # kpartx -a /dev/loop0 # dd if= of=/dev/mapper/loop0p1 # e2fsck -f /dev/mapper/loop0p1 # resize2fs /dev/mapper/loop0p1 # a lot of guides tell you to edit /etc/fst........

yum error "Error: database disk image is malformed" solution

yum -y install mathtools Loaded plugins: fastestmirror Loading mirror speeds from cached hostfile * base: centos.mirror.rafal.ca * epel: mirror.steadfast.net * extras: mirror.agmn.ca * rpmforge: repoforge.mirror.constant.com * updates: centosb5.centos.org extras ........

OpenVZ mismatched kernel and dev when compiling.

./configure ./configure: line 91: cd: /lib/modules/2.6.32-042stab084.25/build: No such file or directory Error: kernel version not found. Please make sure your kernel is configured. dr-xr-xr-x. 4 root root 4096 Feb 21 06:13 .. lrwxrwxrwx 1 root root 45 Feb 21 06:13 build -> ../../../usr/src/kernels/2.6.32-042stab084.25 drwxr-xr-x 2 root root 4096 Feb 12 20........

yum Centos 386 and 64 bit conflict resolution

This can happen when you install RPMForge or other repos with the wrong architecture and here's how you fix it (simply uninstalling won't usually fix it): solution yum clean all yum -y install openvpn Loaded plugins: fastestmirror, presto Loading mirror speeds from cached hostfile * base: mirror.its.sfu.ca * extras: centos.mirror.nexicom.net * rpmforge: mirror.cpsc.ucalgary.ca * up........

OpenVZ Quick Install Copy & Paste for Centos 6

yum -y install wget wget -P /etc/yum.repos.d/ http://ftp.openvz.org/openvz.repo rpm --import http://ftp.openvz.org/RPM-GPG-Key-OpenVZ yum -y install vzkernel vzctl After that just reboot and you may also have to enable ip_forward in /etc/sysctl.conf........

yum error installing php solution - exclude php from being installed from third party repos

Error: Package: php-Monolog-dynamo-1.7.0-1.el6.noarch (epel) Requires: php-aws-sdk Error: php-pecl-zendopcache conflicts with 1:php-eaccelerator-0.9.6.1-1.el6.x86_64 Error: php-xcache conflicts with php-pecl-apc-3.1.9-2.el6.x86_64 Error: php-pecl-zendopcache conflicts with php-pecl-apc-3.1.9-2.el6.x86_64 Error: Package: php-horde-Horde-Vfs-2.1.2-2.el6.noarch (epel) &n........

Centos Howto Upgrade to PHP 5.3 from 5.2

It's not as simple as "yum install" as you can see below and it doesn't stop there. yum install php53 Loaded plugins: fastestmirror Loading mirror speeds from cached hostfile * rpmforge: mirror.us.leaseweb.net * extras: centos.mirror.rafal.ca * updates: centos.mirror.nexicom.net * base: centos.mirror.nexicom.net * addons: centos.mirror.nexicom.net Setting up Install Process........

Directadmin Install Error Cannot find /usr/include/openssl/ssl.h. Did you run the pre-install commands?

Cannot find /usr/include/openssl/ssl.h. Did you run the pre-install commands? http://help.directadmin.com/item.php?id=354 yum -y install openssl*........

Asterisk iptables block bruteforce attacks howto with fail2ban

yum -y install fail2ban vi /etc/fail2ban/jail.conf [asterisk-tcp] enabled = true filter = asterisk action = iptables-multiport[name=asterisk-tcp, port="5060,5061", protocol=tcp] sendmail-whois[name=Asterisk, dest=you@example.com, sender=fail2ban@example.com] logpath = /var/log/asterisk/messages maxret........

kvm centos cannot compile error

./configure ./configure: cannot locate gcc 3.x. please install it or specify with --qemu-cc yum -y install gcc make ./configure ./configure: cannot locate gcc 3.x. please install it or specify with --qemu-cc yum -y install compat-gcc-* ./configure Error: Could not find alsa Make sure to have the alsa libs and headers installed. yum -y install alsa-lib-devel ./configure........

Dell Perc 6/i cannot downgrade

I flashed an LSI Logic firmware to it and it broke the BIOS (cannot do Ctrl+R) for booting purposes but allows other functionality to work normally. I tried downgrading to a Dell firmware for Perc 6i but it won't work, not even with MegaCli wget http://downloads.dell.com/FOLDER00416606M/1/SAS-RAID_Firmware_W83M2_LN32_6.3.1-0003_A14.BIN --2013-08-26 12:53:39-- http://downloads.dell.com/FOLDER00416606M/1/SAS-RAID_Firmware_W83M2_LN32_6.3.1-0003_A14.BIN Resolvi........

pxe-32 tftp open timeout

pxe-32 tftp open timeout The solution was to enable tftp in xinetd with "chkconfig tftp on". See the troubleshooting below: chkconfig --list NetworkManager 0:off 1:off 2:off 3:off 4:off 5:off 6:off acpid 0:off&n........

yum update error

yum update error Traceback (most recent call last): File "/usr/bin/yum", line 29, in ? yummain.user_main(sys.argv[1:], exit_code=True) File "/usr/share/yum-cli/yummain.py", line 229, in user_main errcode = main(args) File "/usr/share/yum-cli/yummain.py", line 145, in main (result, resultmsgs) = base.buildTransaction() &nbs........

rtorrent: symbol lookup error: rtorrent: undefined symbol: _ZN7torrent10ThreadBase8m_globalE solution

The solution is strange but simple and works each time on Centos: yum downgrade libtorrent........

Directadmin error/** Found 7 pre-existing rpmdb problem(s), 'yum check' output follows: e2fsprogs-devel-1.41.12-3.el6.i686 has missing requires of e2fsprogs-libs = ('0', '1.41.12', '3.el6') e2fsprogs-devel-1.41.12-3.el6.i686 has missing requires of l

Solution To The Following: yum -y install zlib-devel yum -y install e2fsprogs* *** Cannot find /usr/include/et/com_err.h. (yum install libcom_err-devel) *** Installation didn't pass, halting install. Once requirements are met, run the following to continue the install: cd /usr/local/directadmin/scripts ./install.sh Common pre-install commands: http://help.directadmin.com/it........

Centos 6 RTL8111/8168B r8169 link up and down error solution/fix

02:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8111/8168B PCI Express Gigabit Ethernet controller (rev 03) For whatever reason it seems the r8169 driver that ships and has shipped with most Linux distros for years is still flawed and does not work properly on these cards, causing 100mbit connectivity when it should be 1gbit and even worse, causing random network dropouts. The r8169 driver in Linux kernels is simply not meant to be used on th........

Setup PXE Boot using Centos and dhcpd, tftp and syslinux

This is something I often setup for clients because it's very helpful for people in datacenters, this allows custom OS installs on demand, you can customize it more by using kickstart etc.. but here's a base I use before customizing more: This little script below will install everything you need to get booting by PXE Linux. It also assumes you set a local IP (be sure not to overwrite your existing IP) on eth0:0 (note the :0) as 192.168.1.10 and it........

KVM compilation issue/solution - Disabling PIE due to missing toolchain support glib-2.12 required to compile QEMU

qemu-kvm-1.2.0]# ./configure Disabling PIE due to missing toolchain support glib-2.12 required to compile QEMU Solution install glib2 *Don't confuse glib2 with glibc, they are different and it may catch some off guard. yum -y install glib2* After that KVM should compile and install just fine.........

Centos 5 and OpenVZ won't boot after kernel install

For whatever reason the current OpenVZ yum repo file enables the RHEL6 version of OpenVZ, why is this bad? Because if you're running Centos 5 it still defaults to using the kernel from RHEL6 which won't work on RHEL5/Centos 5. Ionly realized this after wondering why I couldn't boot into OpenVZ that it was using one meant for RHEL6. To fix the problem you have to edit /etc/yum.repos.d/openvz.repo and disable the "[openvz-kernel-rhel6]" section by changing........

Linux/Centos how to block SSH bruteforce/dictionary attacks automatically with denyhosts

A lot of people become nervous (and understandably so) when checking their auth or security logs, in Centos /var/log/secure and see dozens, hundreds of even thousands of attempted logins to various services, especially SSH. Of course you could manually block these people/IPs but no one has time to read the logs like that, what if some program or script could do it for you? This is what denyhosts does for you, it checks the logs and based on a certain number of failed SSH attem........

Centos how to upgrade from PHP 5.2 to 5.3 without downtime

This may sound silly but there will be conflicts/issues with the default Centos repository so you have to use a third party like remi (I prefer not to do this but it's the only option unless you migrate your sites/data to another server or can stand some downtime-not an option IMHOon a production server). You may need to upgrade to PHP5.3 to run Joomla or many other reasons. Your host needs to use PHP 5.2.4 or higher to run this version of Jo........

scp not found - solution

Some minimal installs of Centos may be missing the scp command, which is actually part of the "openssh-clients" package. scp not found yum install openssh-clients........

rpmforge: [#### ] 471/10722Segmentation fault yum[18934]: segfault at 0000000000000000 rip 00002ade62153a30 rsp 00007fff76f9fe58 error 4

A few days ago this happened on multiple Centos 5 servers and apparently anyone using rpmforge was affected by this error and there was no solution other than disabling that repo to fix it. To some this highlighted a few points, that there is a reason RHELexists with full paid support, and also that this could be a vulnerability and huge flaw with yum. A yum search or install should not segfault just because the rpmforge repo goes down. Fortunately it came back up........

Openvz YUM Error Solution to "[Errno -1] Metadata file does not match checksum Trying other mirror."

It's weird because I have a nearly identical box and setup and I can update the ovzkernel-PAE* just fine but on this box it doesn't work. I only get this error with the openvz.repo and not others such as Centos-Base.repo With my other server it works normally: ================ Setting up Update Process Resolving Dependencies --> Running transaction check ---> Package ovzkernel-PAE.i686 0:2.6.18-238.12.1.el5.0........

vnstat setup guide/tutorial

yum -y install vnstat chown nobody.nobody -R /var/lib/vnstat/ #replace venet0 below with your desired interface sudo -u nobody vnstat -u -i venet0 #edit: vi /etc/sysconfig/vnstat #VNSTAT_OPTIONS="-i venet0" # only use the sed below if you are using venet0 instead of eth0 or replace accordingly sed -i 's/eth0/venet0/g' /etc/sysconfig/vnstat [root@monitor]# yum install vn........

Enable SPAMASSASSIN on Postfix in 5 minutes

Centos 5 Postfix and SPAMASSASSIN Tutorial yum install spamassassin chkconfig spamassassin on vi /etc/mail/spamassassin/local.cf ############## #required_hits 5 #report_safe 0 #rewrite_header Subject [SPAM] #5 is the least restrictive (means only the most obvious SPAM is caught. 0 is obviously the most restrictive/sensitive and would have lots of false positives require........

Directadmin DA Install Guide

yum -y install openssl* gcc-c++ gcc flex g++ make;wget http://www.directadmin.com/setup.sh;chmod +x ./setup.sh;./setup.sh #enable SSL /usr/bin/openssl req -x509 -newkey rsa:1024 -keyout /usr/local/directadmin/conf/cakey.pem -out /usr/local/directadmin/conf/cacert.pem -days 9999 -nodes chown diradmin:diradmin /usr/local/directadmin/conf/cakey.pem chmod 400 /usr/local/directadmin/conf/cakey.pem sed -i "s/SSL=0/SSL=1/g" /usr/local/dire........

Thunderbird/MBOX to IMAP/Maildir migration done easy with mb2md

Convert MBOX Mail files into Maildir using Linux *You need perl an the TimeDate module Get the free Perl script mb2md from the project/author's site: wget http://batleth.sapienti-sat.org/projects/mb2md/mb2md-3.20.pl.gz gunzip mb2md-3.20.pl.gz #remember you need timedate or you'll get this error: ./mb2md-3.20.pl Can't locate........

PHP5 & Apache Blank/White Screen/Page PHP won't work

PHP5 & Apache Blank Screen/Page The PHP package is installed and works from the CLI Error reporting is enabled The only way I could get it working was: rm /etc/php.ini yum remove php yum install php-* -x php-pear* -x php-pecl* Interestingly enough reinstalling php did not bring back the deleted php.ini but everything is working. ........

PHP Fatal error: Call to undefined function mysql_connect()

PHP Fatal error: Call to undefined function mysql_connect() yum install php-*........

Installing Webmin & Enabling SSL

Webmin Setup Centos 5: wget http://downloads.sourceforge.net/project/webadmin/webmin/1.530/webmin-1.530-1.noarch.rpm?r=http%3A%2F%2Fwww.webmin.com%2Fstandard.html&ts=1294339690&use_mirror=surfnet [1] 24229 [2] 24230 [root@host ~]# --2011-01-06 21:48:20-- http://downloads.sourceforge.net/project/webadmin/webmin/1.530/webmin-1.530-1.noarch.rpm?r=http%3A%2F%2Fwww.webmin.com%2Fstandard.html Resolving downloads.sourceforge.net... 216.34.181.........

yum in Centos 5/Xen halts and exits suddenly

yum exits in the middle The problem is this VPS seems to be an OpenVZ template from HyperVM. The only way to make it work was to disable i386 packages since this was an x64 kernel. That shouldn't be necessary but it was the only way to make yum stop quitting after the first package or two. I couldn't find any issue by checking the logs either. echo y|yum install vim-minimal telnet expect jwhois net-tools slocate iptables elinks gawk L........

yum error with some versions of Centos Refusing to automatically import keys when running unattended. Use "-y" to override.

Refusing to automatically import keys when running unattended. Use "-y" to override. When using echo y|yum install gcc Fix with rpm --import /etc/pki/rpm-gpg/RPM-GPG-KEY*........

http://apt.sw.be/redhat/el5/en/i386/test/repodata/repomd.xml: [Errno 14] HTTP Error 404: Not Found Trying other mirror.

http://apt.sw.be/redhat/el5/en/i386/test/repodata/repomd.xml: [Errno 14] HTTP Error 404: Not Found Trying other mirror. Error: Cannot retrieve repository metadata (repomd.xml) for repository: rpmforge-testing. Please verify its path and try again Notice it is complaining about "rpmforge-testing", just disable it for now: Solution is to edit the repo: vi /etc/yum.repos.d/rpmforge-testing.repo........

Openvz Quick Install for CentOS 5 Tutorial

cd /etc/yum.repos.d wget http://download.openvz.org/openvz.repo rpm --import http://download.openvz.org/RPM-GPG-Key-OpenVZ yum install ovz-kernel-PAE Now remember to set /etc/sysctl.conf to "net.ipv4.ip_forward = 1" You can apply the change immediately by running sysctl -w net.ipv4.ip_forward = 1 but remember that you still have to set sysctl.conf sysctl -p will load and apply any changes to s........

Installing Virtualbox on Centos 5.5

wget http://download.virtualbox.org/virtualbox/3.2.8/VirtualBox-3.2-3.2.8_64453_rhel5-1.i386.rpm rpm -i http://download.virtualbox.org/virtualbox/3.2.8/VirtualBox-3.2-3.2.8_64453_rhel5-1.i386.rpm error: Failed dependencies: libGLU.so.1 is needed by VirtualBox-3.2-3.2.8_64453_rhel5-1.i386 libSDL-1.2.so.0 is needed by VirtualBox-3.2-3.2.8_64453_rhel5-1.i386 libXmu.so.6 is needed b........

Solution - error while loading shared libraries: libgd.so.2: cannot open shared object file: No such file or directory

error while loading shared libraries: libgd.so.2: cannot open shared object file: No such file or directory Solution Install gd: yum install gd After that whatever you are compliing should be happy.........

jailkit for chroot ssh account security tutorial and fix for error

This was done on Centos butI think it's easier on Debian machines, the paths that it is set to use are tailored towards Debian, so there is some fiddling that needs to be done on Centos. This is for chrooting ssh, but jailkit has other uses than just SSH jails but I won't cover them in this writeup. 1. Install jailkit yum install jailkit 2. Setup Jail Home mkdir /home/jail chown root:root /home/ja........

Linux Centos/RHEL can't find php/apache/httpd/mysql/ftp/exim/sendmail ?

I wasted a lot of time wondering why I could never find those packages. Check the /etc/yum.conf file and at the bottom look for the "exclude=" line. Below is what I found in mine exclude=apache* httpd* mod_* mysql* MySQL* da_* *ftp* exim* sendmail* php* bind-chroot* Just remove those entries or uncomment that line and you'll get access to the missing applications.........

Compile PHP 5.3.2 on Centos 5 and CPanel/WHM because of error - Fatal error: Call to > undefined function imagecreatefromjpeg()

This function and others may not work with the stock PHPinstall on Centos/CPanel: Fatal error: Call to > undefined function imagecreatefromjpeg() Even with libjpeg-devel installed it won't work because PHP was not compiled with jpeg support, so we have to do the dirty work ourselves :) Here is the command/yum's I did to install missing libraries for PHP that configure will complain about (yes it is a one by one process). yum install bzip2-........

Picking an FTPD (vsftpd) Server in Linux Centos/Debian

I decided on using yum to help me decide even though I normaly use proftpd I decided to see what else I could find. yum search ftp Loaded plugins: fastestmirror Loading mirror speeds from cached hostfile * rpmforge: ftp-stud.fht-esslingen.de * base: mirrors.netdna.com * updates: updates.interworx.info * addons: yum.singlehop.com * extras: mirrors.netdna.com rpmforge........

heartbeat is stopped for some reason

heartbeat is stopped for some reason Anyway hnode2 was active and the services are running fine but I see heartbeat has been stopped somehow. Here is the last log I see of heartbeat: [quote:23c84415f5] Sep 9 17:15:32 hnode2 heartbeat: [16738]: info: MSG stats: 9/1762471 ms age 0 [pid16738/MST_CONTROL] Sep 9 17:15:32 hnode2 heartbeat: [16738]: info: cl_malloc stats: 716/51784021 152624/74519 [pid16738/MST_CONTROL] Sep 9 17:15:32........

PHP cannot access /usr/bin/openssl

PHP cannot access /usr/bin/opensslI have verified the username that runs the process is able to access /usr/bin/openssl and it does exist but the PHP script is saying it doesn't exist: [code:1:1fd0f3abbe] if (!file_exists($OPENSSL)) { //echo "ERROR: OPENSSL $OPENSSL not foundn"; }[/code:1:1fd0f3abbe] I don't get itI can clearly see the contents of /usr/bin by using the PHP system fu........

Centos 4.3 x64 & VMWare Server Beta

Centos 4.3 x64 & VMWare Server Beta[code:1:6d0b2c8c2f] The correct version of one or more libraries needed to run VMware Server may be missing. This is the output of ldd /usr/bin/vmware: linux-gate.so.1 => (0xffffe000) libm.so.6 => /lib/tls/libm.so.6 (0xf7fbd000) libdl.so.2 => /lib/libdl.so.2 (0xf7fb9000) libpthread.so.0 => /lib/tls/libpthread.so.0 (0xf7fa7000) libX11.so.6 => not f........

Upgrade Release Kernel Tips

Upgrade Release Kernel TipsThis is for CentOS 3.1 to 3.8 but the methodology will apply everywhere. I ran into a problem first of all with a non-booting system after running #yum update centos-release It took me to 3.8 and upgraded all the other packages [b:7e931c835d]BUT[/b:7e931c835d] because of some stupid flags enabled in /etc/yum.conf the KERNEL WASN'T UPGRADED SO AFTER BOOTING, WELL IT DIDN'T BOOT OF COURSE :) H........

Updated to Version 3.8 and can't login

Updated to Version 3.8 and can't loginSSHD accepts my password but then hangs at "Last login: Wed Sep 13 21:30:02 2006 from" This occurred during a yum update after upgrading my release, installing the new kernel and rebooting. I got kicked out of sshd after seeing the following during yum update: telnet 100 % done 85/476 tux 100 % done 86/476 ntsysv 100 % done 87/476 rpmdb-redhat 94 % done 88/476........

locate: command not found (slocate database needed)

locate: command not found (slocate database needed)For some versions especially older ones like 3.x they might not have the "slocate" database. Meaning a "locate somefile" command doesn't work. Just install "slocate" [code:1:d6d717421c]yum install slocate[/code:1:d6d717421c] Then run: [code:1:d6d717421c]updatedb[/code:1:d6d717421c] And you're good to go :)........

Need identd for port 113 ? Install authd

Need identd for port 113 ? Install authdyum install authd Happy identing :)Actually it's not that simple. It installs as an "xinetd" service and is disabled and turned off by deafult. To enable it run: [code:1:8c94df8319] chkconfig --level 3 auth on service xinetd restart [/code:1:8c94df8319] This will set identd aka authd to start by default. service xinetd resta........

Updating yum repos for DAG /etc/yum.repos.d

Updating yum repos for DAG /etc/yum.repos.dIn /etc/yum.repos.d [quote:96456b2ab9]Create any file such as "CentOS-Dag.repo" in /etc/yum.repos.d[/quote:96456b2ab9] Add the following to the above file: [code:1:96456b2ab9] [dag] name=Dag RPM Repository For Red Hat Enterprise Linux baseurl=http://dag.atrpms.net/redhat/el$releasever/en/$basearch/dag/ http://dag.freshrpms.net/redhat/e........

yum error not working rpmdb: mmap: No such device TypeError: rpmdb open failed

Loaded plugins: fastestmirror rpmdb: mmap: No such device error: db4 error(19) from dbenv->open: No such device error: cannot open Packages index using db3 - No such device (19) error: cannot open Packages database in /var/lib/rpm Traceback (most recent call last): File "/usr/bin/yum", line 29, in ? yummain.user_main(sys.argv[1:], exit_code=True) File "/usr/share/yum-cli/yummain.py&qu........

sudo: Error dropping capabilities, aborting in Linux Centos 5.3

For some reason Ikeep getting this error when trying to run a sudo command eg: sudo -u someuser somecommand sudo: Error dropping capabilities, aborting My version of sudo is:sudo-1.6.9p17-3.el5_3.1 and I've heard that version 1.7 fixes everything. The only thing is yum does not think sudo has any update. Iguess the new version has not been committed to the RPM repository yet. This is really a huge and ann........

Writing/Burning a data CD-R/DVD-R or DVD+RW in Unix/Linux

There's a lot of outdated information and confusion for system administrator's out there. One annoying task for many an Administrator has been backing up data in Linux. You don't need any GUI tools such as K3B or GnomeBaker. Both are excellent tools but for veteran command line users working remotely, using the keyboard is a great and possibly automated way to save yourself pain and hassle. At a later date we'll cover how scripting can automatically backup certain........