Information Security

SELinux prevented ruby from reading files stored on a NFS filesytem

While working on a server farm for a client I kept running into some issues with one of the servers. The issue appeared to be a single CentOS Linux server in a cluster of ten CentOS Linux servers configured exactly the same as the other nine CentOS Linux servers was having issues writing to a network storage device. Initially I figured that the CentOS Linux server having the issues had some permission issues with the directory that was mounted to the SAN (Storage Area Network) however after minimal troubleshooting it was verified that the permissions were identical to the other servers. I started looking through other logs on the server having the issue and located some SELinux errors that were noticeably related to the issue at hand. Below I describe where the SELinux error was located, what the specific errors were, and how I was able to resolve the errors on this specific CentOS Linux server.

Technology Insights

CentOS Linux Error: -bash: traceroute: command not found

You may receive the below error on a Linux server which is caused by traceroute not being installed. The chances are that if traceroute is not installed that the tracepath package is installed. The difference between the two is that tracepath does not require superuser privileges and traceroute does require super user privileges. Below is information on the traceroute error, how to install traceroute using yum on CentOS Linux, or how to alternatively use tracepath instead of traceroute.