An awesome host inspection tool, with tcpdump like tool and an interface similar to [[top]] et al. - http://www.sysdig.org/

Installation - CentOS

Their shell script installs epel from a 3rd party source, so it's best to use this method instead:

rpm --import https://s3.amazonaws.com/download.draios.com/DRAIOS-GPG-KEY.public && \
curl -s -o /etc/yum.repos.d/draios.repo http://download.draios.com/stable/rpm/draios.repo && \
yum -y install kernel-devel-$(uname -r) && \
yum -y install sysdig

Examples

Simple usage

sysdig

Write a system trace file

sysdig -w tracefile.scap

Replay a tracefile

sysdig -r tracefile.scap

Show filters

sysdig -l

Show activity for access to a given file

sysdig -l fd.name=/etc/hosts

Show shell commands for all users

sysdig -pc -c spy_users

Spy on a user and exclude a process

sysdig -pc -c spy_users proc.name!=gmetric

Or exclude multiple processes

sysdig -pc -c spy_users "not proc.name in ( gmetric, awk, sed, grep )"

Show a top like interface

csysdig

Links