How To Linux

Yum on one of my centos boxes simply would not work.  Once you entered a yum command such as;

yum clean all

yum upgrade

it hung and would not work.

Apparently I needed to remove the __db.* in /var/lib/rpm

rm -f /var/lib/rpm/__db.*

See this link for more info - http://www.serpentine.com/blog/2007/01/04/dealing-with-yum-hangs-on-fc6/

Puppet is an open-source next-generation server automation tool. It is composed of a declarative language for expressing system configuration, a client and server for distributing it, and a library for realizing the configuration.

Setup the EPEL repos for Centos – choose the correct package depending on  your installation.

rpm -Uvh http://download.fedora.redhat.com/pub/epel/5Server/x86_64/epel-release-5-3.noarch.rpm

rpm -Uvh http://download.fedora.redhat.com/pub/epel/5/i386/epel-release-5-3.noarch.rpm

Install puppet-server

yum install puppet-server

The 1.8.5 branch of Ruby shipped will RHEL5 can exhibit memory leaks. So install ruby 1.8.6++ (I did not on this server as it was  test not a production server).

Install the help docs

yum install ruby-rdoc

Create a manifest file at /etc/puppet/manifests/default.pp

vi /etc/puppet/manifests/default.pp

put this in it

# Create “/tmp/testfile” if it doesn’t exist.

class test_class {

    file { “/tmp/testfile”:

       ensure => present,

       mode   => 644,

       owner  => root,

       group  => root

    }

}

# tell puppet on which client to run the class

node pclient {

    include test_class

}

Start the puppet server

service puppetmaster start

Enable start on boot

chkconfig puppetmaster on

Now to install the Puppet Client on another server

Setup the EPEL repos for Centos – choose the correct package depending on  your installation.

rpm -Uvh http://download.fedora.redhat.com/pub/epel/5Server/x86_64/epel-release-5-3.noarch.rpm

rpm -Uvh http://download.fedora.redhat.com/pub/epel/5/i386/epel-release-5-3.noarch.rpm

Install puppet

yum install puppet

Setup puppet client to generate its own certificate request to the server

/etc/init.d/puppet once -v

Sign the certificate request on the puppet master server.  Use puppetca –list to see if any are available to sign.

puppetca –sign puppet01

Puppet01 must be the fully qualified domain name (FQDN) of you client server.

Run this on the client server again to retrieve the certificate

/etc/init.d/puppet once -v

Make the puppet start with the system

chkconfig puppet on

Make sure it is working on the client server.

puppet –test

You should see a dialog that creates the file /tmp/testfile

You can push x server gui’s from a remote server to your local machine.  This is how to send an x server gui from a remote centos machine to your vista machine.

Install Cygwin, choose the default installation package for X11 (follow the documentation).

Once installed, start the xserver with

sh /usr/bin/startxwin.sh

see - http://x.cygwin.com/docs/ug/using.html#using-starting-sh

This will create a xserver icon in the bottom right corner of your taskbar.  Right click this icon and select Applications and choose xterm.  Once this fires up, connect to your remote server with ssh.

In the xterm session, type;

ssh -X user@sshserver.com

Once logged into the remote server you can start your apps within the ssh session and they are piped to you cygwin xserver.

The reason I care, I was trying to get a Jmeter gui running locally for a remote server.

dd if=/dev/zero of=my-image.fs bs=1M count=1024

mke2fs -F -j my-image.fs

mkdir /mnt/ec2-fs

mount -o loop my-image.fs /mnt/ec2-fs

mkdir /mnt/ec2-fs/dev

/sbin/MAKEDEV -d /mnt/ec2-fs/dev/ -x console

/sbin/MAKEDEV -d /mnt/ec2-fs/dev/ -x null

/sbin/MAKEDEV -d /mnt/ec2-fs/dev/ -x zero

mkdir /mnt/ec2-fs/etc

[main]

cachedir=/var/cache/yum

debuglevel=2

logfile=/var/log/yum.log

exclude=*-debuginfo

gpgcheck=0

obsoletes=1

pkgpolicy=newest

distroverpkg=redhat-release

tolerant=1

exactarch=1

reposdir=/dev/null

metadata_expire=1800

[base]

name=CentOS-5.2 – Base

baseurl=http://mirror.centos.org/centos/5.2/os/i386/

gpgcheck=1

gpgkey=http://mirror.centos.org/centos/RPM-GPG-KEY-centos5.2

priority=1

protect=1

#released updates

[update]

name=CentOS-5.2 – Updates

baseurl=http://mirror.centos.org/centos/5.2/updates/i386/

gpgcheck=1

gpgkey=http://mirror.centos.org/centos/RPM-GPG-KEY-centos5.2

priority=1

protect=1

#packages used/produced in the build but not released

[addons]

name=CentOS-5.2 – Addons

baseurl=http://mirror.centos.org/centos/5.2/addons/i386/

gpgcheck=1

gpgkey=http://mirror.centos.org/centos/RPM-GPG-KEY-centos5.2

priority=1

[extras]

name=CentOS 5.2 Extras $releasever – $basearch

baseurl=http://mirror.centos.org/centos/5.2/extras/i386/

enabled=1

mkdir /mnt/ec2-fs/proc

mount -t proc none /mnt/ec2-fs/proc

yum -c yum-xen.conf –installroot=/mnt/ec2-fs -y groupinstall Core

vi /mnt/ec2-fs/etc/sysconfig/network-scripts/ifcfg-eth0

DEVICE=eth0

BOOTPROTO=dhcp

ONBOOT=yes

TYPE=Ethernet

USERCTL=yes

PEERDNS=yes

IPV6INIT=no

vi /mnt/ec2-fs/etc/sysconfig/network

NETWORKING=yes

vi /mnt/ec2-fs/etc/fstab

/dev/sda2  /mnt      ext3    defaults        1 2

/dev/sda3  swap      swap    defaults        0 0

chroot /mnt/ec2-fs /bin/sh

chkconfig –level 345 sshd on

exit

umount /mnt/ec2-fs/proc

umount -d /mnt/ec2-fs 

yum install ruby

wget http://s3.amazonaws.com/ec2-downloads/ec2-ami-tools.noarch.rpm

rpm -Uvh ec2-ami-tools.noarch.rpm

ec2-bundle-image -i my-image.fs -c my-cert.pem -k my-private-key.pem -u 12345678(amazon account id)  

ec2-upload-bundle -b my-bucket -m image.manifest -a my-aws-access-key-id -s my-secret-key-id 

I have used this SSH client for the last 6 months and can heartily recommend it.

http://www.bitvise.com/tunnelier

Below are the features directly ripped from their site;

• one of the most advanced graphical SFTP clients;
• state-of-the-art terminal emulation with support for the bvterm, xterm, and vt100 protocols;
• support for corporation-wide single sign-on using SSPI (GSSAPI) Kerberos 5 and NTLM user authentication, as well as Kerberos 5 host authentication;
• support for RSA and DSA public key authentication with comprehensive user keypair management;
• powerful SSH port forwarding capabilities, including dynamic forwarding through integrated SOCKS and HTTP CONNECT proxy;
• powerful command-line parameters which make Tunnelier highly customizable and suitable for use in specific situations and controlled environments;
• an advanced, scriptable command-line SFTP client (sftpc);
• a scriptable command-line remote execution client (sexec) and a command-line terminal emulation client (stermc);
• an FTP-to-SFTP bridge allowing you to connect to an SFTP server using legacy FTP applications;
• WinSSHD remote administration features;
• single-click Remote Desktop forwarding.

Scalr is a fully redundant, self-curing and self-scaling hosting environment utilizing Amazon’s EC2.

It allows you to create server farms through a web-based interface using prebuilt AMI’s for load balancers (pound or nginx), app servers (apache, others), databases (mysql master-slave, others), and a generic AMI to build on top of. (see http://code.google.com/p/scalr/)

Install the necessary packages

You will need utterramblings repo’s to install PHP 5.2.6, see - http://www.how-to-linux.com/2008/12/how-to-upgrade-to-php-526-on-centos-52/

yum install httpd mysql-server gcc mysql-server php-devel php-cli php-mysql php-mcrypt php-mhash php-snmp php-pear php-soap php-xml

You will need to install ssh2 php support, currently it is still in beta use;

libssh2 from yum does not work so build the one scalr needs from source

wget http://downloads.sourceforge.net/libssh2/libssh2-1.0.tar.gz?modtime=1230332100&big_mirror=0

./configure

make

make install

Then

pecl install ssh2-beta

Now you need to update your php.ini file by adding

extension=ssh2.so

Restart your webserver

service httpd restart

See install instructions – http://th.php.net/manual/en/ssh2.installation.php

Use the scalr’s checkenvironment.php script to check everything is ok.

wget http://scalr.googlecode.com/files/checkenvironment.php

chmod 777 checkenvironment.php

Run it on the command line

php checkenvironment.php

Download the scalr tar package 

wget http://scalr.googlecode.com/files/scalr-1.0RC3.tar.gz

untar

tar xvfz scalr-1.0RC3.tar.gz

mv the contents of the app folder to /var/www/html/

mv scalr/app/* /var/www/html/

Set permissions on the following folders (and subfolders) and files to 777 (world-writable):

cache

cron/cron.pid

etc/.passwd

Create a mysql database and import data

mysql -u root

create database scalr;

quit

mysql -u root -h localhost scalr < sql/database.sql

Edit the database config settings in etc/config.ini file.

Set Cron jobs

For system to work properly, it needs to run a few tasks periodicaly. Scalr has a single cron/cron.php file that must be executed with various command-line switches. The following tasks must be sheduled:

* * * * * /path/to/php -q /scalr_home_dir/cron/cron.php –Poller

1 1 * * * /path/to/php -q /scalr_home_dir/cron/cron.php –RotateLogs

*/15 * * * * /path/to/php -q /scalr_home_dir/cron/cron.php –MySQLMaintenance

*/6 * * * * /path/to/php -q /scalr_home_dir/cron/cron.php –DNSMaintenance

*/3 * * * * /path/to/php -q /scalr_home_dir/cron/cron.php –DNSZoneListUpdate

*/2 * * * * /path/to/php -q /scalr_home_dir/cron/cron.php –DBQueueEvent

*/11 * * * * /path/to/php -q /scalr_home_dir/cron/cron.php –Cleaner

*/2 * * * * /path/to/php -q /scalr_home_dir/cron/cron.php –EBSQueue

Scalr needs your keys..

Sclar needs to have AWS access.

Now goto http://localhost/

username and password is admin/admin

I had a 403 error when trying to access scalr, this was because I had SElinux enabled, disable this if its a test machine.

After the install I found this, anothe useful resource if you have problems - http://groups.google.com/group/scalr-discuss/web/scalr-on-centos-5-install-notes

This is a combination of all my instructions on how to setup redmine on Centos.  Its still a work in progress so please note any problems in comments.

Install Ruby on Rails

yum install ruby ruby-devel ruby-libs ruby-irb ruby-rdoc ruby-mysql

Download and install ruby gems

wget http://rubyforge.org/frs/download.php/45905/rubygems-1.3.1.tgz

tar xvf rubygems-1.3.1.tgz

cd rubygems-1.3.1

ruby setup.rb

Install Rails

gem install rails

Install Redmine

go to /opt

cd /opt

Get latest source code from http://www.redmine.org

unzip redmineXXXX.zip

Create a Database for Redmine

mysql -u root -p

create database redmine character set utf8;

exit

Configure the Redmine database connection settings

Copy config/database.yml.example to config/database.yml and edit this file in order to configure your database settings for “production” environment.

cp /opt/redmine-0.7.3/config/database.yml.example /opt/redmine-0.7.3/config/database.yml

edit database.yml

production:

adapter: mysql

database: redmine

host: localhost

username: yourusername

password: yourpassword

socket: /var/lib/mysql/mysql.sock

Run the following command in /opt/redmine-0.7.3/

rake db:migrate RAILS_ENV=”production”

If you get this error message: “cannot connect to mysql: No such file or directory – /tmp/mysql.sock”, You forgot to specify the socket location in config/database.yml – see above.

This will create tables and an administrator account.

Run this command to load default data into db.

rake redmine:load_default_data RAILS_ENV=”production”

Test the installation by running WEBrick web server:

ruby script/server -e production

Once WEBrick has started, point your browser to http://localhost:3000/. You should now see the application welcome page.

Use default administrator account to log in:

login: admin

password: admin

You can go to Admin & Settings to modify application settings.

You must install Rmagick as well for the nice Gant charts.

yum install ImageMagick

yum install ImageMagick-devel

gem install rmagick -v 1.15.13 –no-rdoc –no-ri

How to Autocreate SVN repositories with Redmine

Create a repository folder.

mkdir /svn

Change the owner and group to root.apache

chown -R root.apache /svn

Change the permissions

chmod 0750 /svn

Configure subversion to be browsed, goto /etc/httpd/conf.d

vi subversion.conf

Insert the following at the bottom

<Location /svn>

DAV svn

SVNParentPath /svn

SVNListParentPath on

</Location>

If you get ‘Could not open the requested SVN filesystem’ when you try to browse to your repository http://localhost/svn then you have used SVNPath instead of SVNParentPath, just update your subversion.conf and that should fix this issue.  This could also be a permission error related to the file permissions of your svn repository, make sure they are readable by apache.

Run the following command to test that it works

ruby reposman.rb -redmine localhost:3000 -svn-dir /svn -owner apache -url http://localhost/svn/ -verbose

If it does not, and fails with this error

/usr/lib/ruby/1.8/rdoc/ri/ri_options.rb:53: uninitialized constant RI::Paths (NameError)

from /usr/lib/ruby/1.8/rdoc/usage.rb:72:in ‘require’

from /usr/lib/ruby/1.8/rdoc/usage.rb:72

from reposman.rb:59:in ‘require’

from reposman.rb:59

Then you need to edit the reposman.rb file and add require statement require ‘rdoc/ri/ri_paths’ above all the other require statements.

require ‘rdoc/ri/ri_paths’

You need to add this to your crontab

5 * * * * ruby /opt/redmine-0.8.0_RC1/extra/svn/reposman.rb -redmine localhost:3000 -svn-dir /svn -owner apache -url http://localhost/svn/ -verbose >> /var/log/reposman.log

Setup permission for SVN to use apache etc

I found the instructions at http://www.redmine.org/wiki/redmine/Repositories_access_control_with_apache_mod_dav_svn_and_mod_perl did not work for me. I managed to get it working doing the following;

You do not need to but you can set subversion 1.54 by installing the RPMForge repos, follow these instructions – http://wiki.centos.org/AdditionalResources/Repositories/RPMForge

Get the necessary packages

yum install mod_dav_svn mod_perl perl-Apache-DBI perl-Digest-SHA1 perl-DBD-mysql subversion

Copy Redmine.pm from /opt/redmine-0.7.3/extra/svn/Redmine.pm to /usr/lib/perl5/vendor_perl/5.8.8/Apache/

cp /opt/redmine-0.7.3/extra/svn/Redmine.pm /usr/lib/perl5/vendor_perl/5.8.8/Apache/

create a file in /etc/httpd/conf.d/ called redmine.conf and put this in it.

PerlLoadModule Apache::Redmine

<Location /svn>

DAV svn

SVNParentPath “/svn”

AuthType Basic

AuthName redmine

Require valid-user

PerlAccessHandler Apache::Authn::Redmine::access_handler

PerlAuthenHandler Apache::Authn::Redmine::authen_handler

## for mysql

RedmineDSN “DBI:mysql:database=da;host=my.db.server”

## for postgres

# RedmineDSN “DBI:Pg:dbname=databasename;host=my.db.server”

RedmineDbUser “redmine”

RedmineDbPass “password”

</Location>

# a private location in read only mode to allow Redmine browsing

<Location /svn-private>

DAV svn

SVNParentPath “/svn”

Order deny,allow

Deny from all

# only allow reading orders

<Limit GET PROPFIND OPTIONS REPORT>

Allow from redmine.server.ip

</Limit>

</Location>

The error I received from using the Redmine-0.7.X was;

‘Invalid command ‘RedmineDSN’, perhaps misspelled or defined by a module not included in the server configuration’

This is related to not copying Redmine.pm to /usr/lib/perl5/vendor_perl/5.8.8/Apache

Install a Mongrel Front to Apache

Taken from http://www.redmine.org/wiki/redmine/HowTo_run_Redmine_with_a_Mongrel_cluster

Install Mongrel

gem install mongrel mongrel_cluster daemons

Configure the Mongrel Cluster for redmine.

cd /opt/redmine

mongrel_rails cluster::configure -e production -p 8000 -N 3 -c /opt/redmine-0.8.0_RC1 -user apache -group apache

Start the Cluster

mongrel_rails cluster::start

Configure apache as the load balancer

create a new config file in /etc/httpd/conf.d

vi /etc/httpd/conf.d/redmine.conf

paste this into the file

<VirtualHost *>

ServerName your.domain.name

DocumentRoot /opt/redmine-0.8.0_RC1

<Directory “/opt/redmine-0.8.0_RC1/public”>

Options FollowSymLinks

AllowOverride None

Order allow,deny

Allow from all

</Directory>

<Proxy balancer://redmine_cluster>

Order allow,deny

Allow from all

BalancerMember http://127.0.0.1:8000

BalancerMember http://127.0.0.1:8001

BalancerMember http://127.0.0.1:8002

</Proxy>

RewriteEngine On

RewriteCond %{DOCUMENT_ROOT}/%{REQUEST_FILENAME} !-f

RewriteRule ^/(.*)$ balancer://redmine_cluster%{REQUEST_URI} [P,QSA,L]

</VirtualHost>

And restart apache

service httpd restart

Install the dependencies

yum install gettext-devel expat-devel curl-devel zlib-devel openssl-devel

Get the git source code

wget http://kernel.org/pub/software/scm/git/git-1.6.1.tar.gz

untar the git source code

tar xvfz git-1.6.1.tar.gz

Install

cd git-1.6.1.tar.gz

make prefix=/usr/local all

make prefix=/usr/local install

Download the Hyperic rpm

wget http://jaist.dl.sourceforge.net/sourceforge/hyperic-hq/hyperic-hq-installer-4.0.2-1.x86_64.rpm

Install required packages

yum install libXp expect

Install mysql if necessary

Install Hyperic 4.0.2 rpm

rpm -Uhv hyperic-hq-installer-4.0.2-1.x86_64.rpm

Start Hyperic by changing to the hyperic user and using hq-server.sh

su hyperic
/opt/hyperic/server-4.0.2/bin/hq-server.sh start

You can now logon using username – hqadmin, password hqadmin.