DavidWittman

Packet Analysis with Wireshark

Links

• Capture files
• CloudShark

Common filters

Source IP is 192.168.1.1

ip.src == 192.168.1.1

DavidWittman

A Brief Introduction to Fabric

Fabric is a deployment management framework written in Python which makes remotely managing multiple servers incredibly easy. If you've ever had to issue a change to a group servers, this should look pretty familiar:

for s in $(cat servers.txt); do ssh $s service httpd graceful; done

Fabric improves on this process by providing a suite of functions to run commands on the servers, as well as a number of other features which just aren't possible in a simple for loop. While a working knowledge of Python is helpful when using Fabric, it certainly isn't necessary. This tutorial will cover the steps necessary to get started with the framework and introduce how it can be used to improve on administering groups of servers.

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You can find the MAC address for LAN1/eth0 (not the BMC MAC) via the SuperMicro IPMI interface by running the following command:

$ ipmitool -U $IPMI_USER -P $IPMI_PASS -H $IPMI_HOST raw 0x30 0x21 | tail -c 18

The eth0 MAC address will be output in this format:

00 25 90 f0 be ef

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iptables n'at

Source NAT

Source NAT changes the source address in IP header of a packet. It may also change the source port in the TCP/UDP headers. The typical usage is to change the a private (rfc1918) address/port into a public address/port for packets leaving your network. Available only in the POSTROUTING chain in iptables.

Syntax

iptables -t nat -A POSTROUTING -i eth1 -j SNAT --to-source 1.2.3.4[:port]

Example

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#!/usr/bin/env python
#
# MongoDB-backed dynamic inventory script for Ansible
# http://docs.ansible.com/intro_dynamic_inventory.html

import os

from argparse import ArgumentParser

import pymongo

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#!/usr/bin/env python

# Parses the output from AWS credential reports and displays
# users which have been inactive for 60+ days.
#
# Usage:
#   audit_iam_accounts.py credential_report.csv <days>
#

import csv

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#!/usr/bin/env bash

# Loads and mounts an ISO over SMB via the
# SuperMicro IPMI web interface
#
# usage: supermicro-mount-iso.sh <ipmi-host> <smb-host> <path>
#  e.g.: supermicro-mount-iso.sh 10.0.0.1 10.0.0.2 '\foo\bar\windows.iso'

set -x

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#!/usr/bin/env bash

# Retrieves the plaintext JNLP from a SuperMicro IPMI webserver
# Usage: supermicro-java-console.sh <hostname>
#        supermicro-java-console.sh 10.1.2.34 > login.jnlp

set -x

HOST="$1"
IPMI_USER=${IPMI_USER:-ADMIN}

DavidWittman

#!/usr/bin/env bash

# vlan-check.sh
#
# Validates the VLAN configuration on an interface
# by creating a tagged subinterface, assigning the
# next available address, and sending a ping to the
# provided gateway IP address.
#
# Supports Ubuntu and RHEL/CentOS. I think.

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#!/usr/bin/env bash

# Issues a reset of the SuperMicro BMC via the web interface
#
# usage: supermicro-bmc-reset.sh <ipmi-host>
#  e.g.: supermicro-bmc-reset.sh 10.0.0.1
#

set -x