There are several common data-gathering tools, and each of them has its own place. Several are already installed for extremely basic information, but for the purposes of this chapter, we need more depth.
For instance, we may want to know the exact distribution of CPU resources, aggregate views of memory paging volume, or disk I/O utilization. For more in-depth needs, we could analyze specific processes for storage interaction or resource locks. If we weren't watching at the exact time a problem occurred, we might want a historical record of various server performance metrics.
In order to have all these capabilities, we must first install the requisite tools. We might find it quite shocking that these tools are not installed by default, considering their role in server administration.
Red Hat-based systems such as Fedora, RHEL, CentOS, and Scientific Linux have a prerequisite package that is not part of the included distribution repositories. To install one of our statistic tools, we need to add the RepoForge library. Red Hat systems can do this by obtaining the most recent RepoForge package for their OS version and architecture at http://repoforge.org/use/.
Once the package is downloaded, it can be installed with this command as a root-level user:
sudo rpm -ivh rpmforge-release-*.rpm
Debian, Mint, or Ubuntu users can install the tools by executing this command as a root-level user:
sudo apt-get install dstat iotop sysstat
Red Hat, Fedora, CentOS, and Scientific Linux users can install the tools by executing this command as a root-level user:
sudo yum install dstat iotop sysstat
Red-Hat-based systems do require a bit of preparation. However, Debian-based distributions have all the necessary elements from the beginning. Once the software sources are accounted for, the only command we need installs all three statistics and monitoring tools simultaneously.
As Red-Hat-based systems require extra work, we've listed two links that provide more information on installing RepoForge on these systems:
- RepoForge: http://repoforge.org/
- CentOS—installing RPMforge: http://wiki.centos.org/AdditionalResources/Repositories/RPMForge