Monthly Archives: February 2015

tune apache performance using mpm prefork module

tune apache performance using mpm prefork module There could be many reasons why your website performance is poor, one of them can possibly be that Apache is not coping with the load. Below you’ll find ready to consume configuration to make Apache performance better using the Apache MPM prefork module. To do this, just include… Read More »

Using a custom kernel with pv-grub

Obligatory Disclaimers pv-grub is an advanced feature. It should only be used by experienced Linux administrators with a demonstrated need to run their own kernels. This is only necessary for older First-Generation servers that do not already include the kernel inside the instance. If you already have a kernel in /boot, it is likely your… Read More »

Basic Network Troubleshooting

ifconfig ifconfig is a basic network information and configuration tool. On a working Cloud Server, its output may look something like this: # ifconfig eth0 Link encap:Ethernet HWaddr 40:40:d9:xx:xx:xx inet addr:67.23.13.xx Bcast:67.23.13.255 Mask:255.255.255.0 inet6 addr: fe80::4240:d9ff:fe05:xxxx/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:36564 errors:0 dropped:0 overruns:0 frame:0 TX packets:11490 errors:0 dropped:0 overruns:0 carrier:0… Read More »

Enabling munin node plug-ins

Munin uses plug-ins to determine what data is gathered and reported. It includes several plug-ins for the types of data most people would be interested in, but not all of those plug-ins are enabled on a fresh installation. What are plug-ins? When a munin node gathers data about a server so it can be graphed,… Read More »

How to install Munin Monitoring systems

e will provide instructions for Installing Munin Monitoring Systems on Ubuntu and Centos/Fedora/Redhat. Munin is a monitoring system that will provide you with your Server stats on a simple to read website. There are two parts of Munin Monitoring Software, Munin Master and Munin node. Muninin Server is the software website and configuration for what… Read More »

Using iotop to check I/O and swap

Watching the disk Sometimes you get more disk activity on your system than you would like. Maybe you saw the problem by running iostat, or you’ve noticed that the system is swapping heavily, or you got an email from support pointing out the problem. In cases like that it’s useful to know which process is… Read More »

Using dstat with scripts and external modules

All-powerful Well, not that. But it can feel a little like that when you fiddle with some more advanced aspects of dstat. Because it can do an awful lot. In the first article of this series we looked at basic usage of dstat – what it does and how to customize its reporting. Now we’ll… Read More »

Tar and untar

ar Although not often used on it’s own, tar (which comes from the words ‘tape archive’ or ‘tape archiving’), does not actually compress files or folders but rather puts them into one file. This is very handy when transferring or backing-up a directory as it produces one easy to manipulate file rather than an unwieldy… Read More »

Using chmod – octal mode

Now we look at the other way chmod can be used – with numbers. This is the more commonly-used format, but also the least user-friendly. The other chmod: with math You’ve learned how to use chmod with symbolic values, but there’s one more approach to chmod you should learn. You will probably hate me for… Read More »

Using chmod – symbolic mode

chmod The basic format for chmod looks something like: chmod [permissions] [file1 file2 file3…] The chmod command looks a lot like chown — the part you’re changing comes first (for chmod, the permissions), then you list one or more file targets for the command. Like the chown command, you can use “-R” to tell chmod… Read More »