Mostly Open Source Utilities for Linux - Mostly Ubuntu

Virus Scan

clamav

Finding Rootkits

rkhunter --propupd
rkhunter -c
chkrootkit

Web Based Firewalls

https://sucuri.net/

Intrusion Detection/Intrusion Prevention

SNORT
OSSEC
NAXSI

Comprehensive security audit

sudo apt-get install tiger
sudo tiger

linux security tools and links

mii-tool 
mii-diag 
ethtool

solve network problems

iptraf
libpcap
tcpdump
MRTG

Processor Activity

top
htop
ps -a
ps -A | less
ps -A | grep nginx

Visualizing processes in a tree like manner

pstree

to kill a process

pgrep nginx
4445
kill 4445

Or combine them

kill $(grep nginx)

Kill all processes for an app at once

killall nginx

Renice to change the priority of a process (they are backwards)

renice 0 PID

or modified again you could use grep.

renice 5 $(grep nginx)

Desktop apps to see network traffic on your server - requires xll or desktop

Autofocus, EtherApe, and vMstat

Maldetect

sudo apt-get install libc6-i386

wget http://www.rfxn.com/downloads/maldetect-current.tar.gz
tar -xvzf maldetect-current.tar.gz
cd maldetect-*
sudo ./install.sh

sudo maldet -d -u

sudo nano /usr/local/maldetect/conf.maldet

email_alert=1
email_addr="samiux@samiux.com"
* change to your email address

quar_hits=1
maxfilesize="10240k"
string_length_scan="1"

clamav_scan=0
* if ClamAV is not installed.

clamav_scan=1
* if ClamAV is installed.

Sources: http://www.howtogeek.com/107217/how-to-manage-processes-from-the-linux-terminal-10-commands-you-need-to-know/ http://samiux.blogspot.com/2014/01/howto-linux-malware-detect-on-ubuntu.html

Edited 20 Oct, 2015 15:02