Here are the commands to install Webmin via Yum:
echo -e "[Webmin]\nname=Webmin Distribution Neutral\nbaseurl=http://download.webmin.com/download/yum\nenabled=1" > /etc/yum.repos.d/webmin.repo
rpm --import http://www.webmin.com/jcameron-key.asc
yum install webmin
A while back I wrote an article on Removing Images from a WordPress Post. Sebastian asked an interesting question; he wanted to remove everything but the images. This is actually pretty straightforward; here is how you do it:
.
.
.
";
$afterEachImage = "Keep in mind this code needs to be in the WordPress Loop and you can control what is around each image using the variables beforeEachImage and afterEachImage above.
Version 1.6 of Browser.php has been released with a lot of updates: http://chrisschuld.com/projects/browser-php-detecting-a-users-browser-from-php/
For those of you who detect Opera 10′s user agent, the Opera team has provide some “fun” for all of us. In my Browser project I started getting feedback that it was broken. At the 10,000′ level, it was defintely broken because the Browser project was returning version 9.8 for Opera version 10.
This is because the Opera dev team decided to leave the version 9.8 user agent string the same and tack on version 10 to end of the string. You can read more about it on their blog.
For those of you using my Browser project have no fear; the new version (1.6+) handles the oddity!
All of our servers are currently based off of the Phoenix, Arizona, USA Timezone. This script allows this conversion from each HN (Host Node):
#!/bin/bash
for i in `vzlist | awk '{print $1}' | grep -v CTID`
do
vzctl exec $f rm -f /etc/localtime 2>/dev/null
vzctl exec $f ln -s /usr/share/zoneinfo/America/Phoenix /etc/localtime
done
From time to time I had have to move one installation of WordPress from one domain (let’s call it domain A) to a new domain (let’s call it domain B). Because WordPress embeds the domain all over the data schema (not faulting; simply disclosing) you have to make a lot of dB changes for the updated site location to function. Here is the quick and dirty way to move the data:
UPDATE wp_posts SET post_content = REPLACE(post_content,"[OLD_DOMAIN]","[NEW_DOMAIN]");
UPDATE wp_posts SET guid = REPLACE(guid,"[OLD_DOMAIN]","[NEW_DOMAIN]");
UPDATE wp_options SET option_value = REPLACE(option_value,"[OLD_DOMAIN]","[NEW_DOMAIN]");
UPDATE wp_postmeta SET meta_value = REPLACE(meta_value,"[OLD_DOMAIN]","[NEW_DOMAIN]");
Finally, for the final bit of trickery if you are using Advanced Caching on the site there is a great place where the localized PATH is hard coded. Edit your new and updated path on file advanced-cache.php
vi wp-content/advanced-cache.php
Here are commands to help adjust the memory / RAM for an OpenVZ VPS:
64MB Guaranteed, 128MB Burstable
cid=1000
vzctl set ${cid} --vmguarpages 64M --save
vzctl set ${cid} --oomguarpages 64M --save
vzctl set ${cid} --privvmpages 64M:128M --save
256MB Guaranteed, 512MB Burstable
cid=1000
vzctl set ${cid} --vmguarpages 256M --save
vzctl set ${cid} --oomguarpages 256M --save
vzctl set ${cid} --privvmpages 256M:512M --save
512MB Guaranteed, 1024MB Burstable
cid=1000
vzctl set ${cid} --vmguarpages 512M --save
vzctl set ${cid} --oomguarpages 512M --save
vzctl set ${cid} --privvmpages 512M:1024M --save
1024MB Guaranteed, 2048MB Burstable
cid=1000
vzctl set ${cid} --vmguarpages 1024M --save
vzctl set ${cid} --oomguarpages 1024M --save
vzctl set ${cid} --privvmpages 1024M:2048M --save
I still use a lot of NFS connections on my equipment and when I create OpenVZ VPS systems I need them to have access to NFS. Here are the steps I use:
From the Host Node (HN):
modprobe nfs
vzctl set 101 --features "nfs:on" --save
From the VPS:
yum -y install nfs-utils nfs-utils-lib
chkconfig --levels 345 portmap on
/etc/init.d/portmap start
Here is my quick-and dirty way to build DNS servers using OpenVZ, CentOS and Bind/Named. This assumes you are creating a new server via OpenVZ. Although Bind is easy to admin with the configuration files recently I have found it is easier to simply admin the zones with Webmin. This setup will create the VPS, install Bind and install Webmin.
Create the VPS:
cid=1161
cd /vz/template/cache/
wget http://download.openvz.org/template/precreated/centos-5-x86_64.tar.gz
vzctl create ${cid} --ostemplate centos-5-x86_64 --config vps.basic
vzctl set ${cid} --hostname [HOSTNAMEHERE] --save
vzctl set ${cid} --ipadd [IP] --save
vzctl set ${cid} --nameserver [IP] --save
vzctl start ${cid}
vzctl exec ${cid} passwd
vzctl enter ${cid}
From inside the VPS I install bind and webmin
yum -y install bind bind-chroot bind-libs bind-utils caching-nameserver
cd /root
wget http://prdownloads.sourceforge.net/webadmin/webmin-1.480-1.noarch.rpm
rpm -Uvh webmin-1.480-1.noarch.rpm
Now I simply visit webmin’s panel and tap in any new zones (or copy over our zones from another box).
OpenVZ and virtual serving makes this time-consuming task of bringing new boxes up a simple task!
There are a few tutorials out there on installing OpenVZ in CentOS 5.3. Here are the steps I use to install OpenVZ on a brand new installation of CentOS 5.3:
Note: this tutorial / walkthrough is for use 64 bit only
yum -y update
cd /etc/yum.repos.d
wget http://download.openvz.org/openvz.repo
rpm --import http://download.openvz.org/RPM-GPG-Key-OpenVZ
yum -y install ovzkernel.x86_64
yum -y install vzctl.x86_64 vzquota.x86_64
Now; we need to configure the sysctl.conf file for OpenVZ
perl -pi -e 's/net\.ipv4\.ip_forward = 0/net\.ipv4\.ip_forward = 1/' /etc/sysctl.conf
perl -pi -e 's/kernel\.sysrq = 0/kernel\.sysrq = 1/' /etc/sysctl.conf
echo -e "\n\nnet.ipv4.conf.default.proxy_arp = 0\nnet.ipv4.conf.all.rp_filter = 1\nnet.ipv4.conf.default.send_redirects = 1\nnet.ipv4.conf.all.send_redirects = 0\nnet.ipv4.icmp_echo_ignore_broadcasts=1\nnet.ipv4.conf.default.forwarding=1\nkernel.ve_allow_kthreads=1\n" >> /etc/sysctl.conf
perl -pi -e 's/NEIGHBOUR_DEVS=detect/NEIGHBOUR_DEVS=all/' /etc/vz/vz.conf
Disable SELINUX
vi /etc/sysconfig/selinux
Reboot the machine
reboot