Below are the changes applied on the script using the patch:
- Update location for nagios.cfg (/usr/local/nagios/etc/nagios.cfg) which is the normal directory for any nagios installation
- Update merlin target directory (/usr/local/nagios/addons/merlin) since the application is a nagios addons
- Allows script to input the MySQL root password using –db-root-pass variable (original script assumes blank MySQL root password)
- Include checks for accessing MySQL database if the root password is incorrect

The patch can be applied directly in the merlin extracted directory and run patch -p0 -i nstall-merlin.patch. When the updated installation script is run, the output should be similar below

root@server:~/merlin-0.6.6# ./install-merlin.sh –db-root-pass=root
Database settings:
Type (–db-type): mysql
Name (–db-name): merlin
Username (–db-user): merlin
Password (–db-pass): merlin
Root Password (–db-root-pass): root

Path settings:
Nagios config file (–nagios-cfg): /usr/local/nagios/etc/nagios.cfg
Destination directory (–dest-dir): /usr/local/nagios/addons/merlin
Base root (–root):
Installing the following components: db,files,config,init
Does this look ok? [Y/n]

So far that’s it, let me know if there are problem with the patch.

Effective spacing between Access Points using the twice the effective range as the distance between them - Use recommended channel spacing (Channel 1,6,11 or Frequency 2412MHz,2437MHz,2462MHz)

Minimize (or even remove) all security settings on the network interfaces on the switches where the APs connects - Port-security (particularly Cisco IOS) settings are good but need to consider which settings are appropriate as a number of MAC address will be identified on the same port. - User roaming with same IP over different APs can trigger these port-security settings (APs space overlapping can cause this problem) - DHCP snooping should be activated with care as it can block valid multiple DHCP request originating from the Access Points

Consider that not only the laptops connects to the network, you should also consider now mobile devices! - These can easily exhaust all DHCP leases in just a day (how many users have iPhone, Blackberries, and any mobile with WiFi capabilites)

Recommend to shorten the DHCP server lease time to say 10mins upto 30mins. - This will release IP address very quickly on the DHCP but will increase the number DHCP broadcast traffic - Multiple IP address space should be considered in the design while determining the number of concurrent users in the wireless area

Reading the recommended steps are rather vague and not straightforward. Here are direct steps to check what causing the errors on Nagios installation.

1) Make sure Nagios is running in the background

# ps ax | grep nagios 6722 ? Ssl 0:14 /usr/local/nagios/bin/nagios -d /usr/local/nagios/etc/nagios.cfg

If it is not running, execute the command

# usr/local/nagios/bin/nagios -d /usr/local/nagios/etc/nagios.cfg

Since I use Debian, I executed this command,

# /etc/init.d/nagios start

2) Execute pre-flight check commands to check the configuration file

# /usr/local/nagios/bin/nagios -v /usr/local/nagios/etc/nagios.cfg ...snipped... Total Warnings: 0 Total Errors: 0 Things look okay - No serious problems were detected during the pre-flight check

The output should give you indications of any problems in the configuration file

3) Lastly, check the Nagios logs which are normally located in /usr/local/nagios/var/nagios.log (use tail command if log file is very long)

From these steps, you can properly diagnose the problem and correct them (if ever )

Cisco IOS has a command which make the LED of the AP to blink in order to be identified from the pack.

ap#led flash ? <1-3600> number of sec to flash disable stop flashing the LEDs ap#sh led flash LED Flash is disabled ap#led flash ap#sh led flash LED Flash is enabled

With this command, you can physically locate the APs from the ceiling.

# Define the interface where Samba listens IF_INT=eth0 # Define the list of host allowed to connect to the server separate by space and note the /32 subnet HOSTS="192.168.1.100/32 192.168.1.200/32 192.168.1.201/32" # This is the FOR loop for SOURCE in $HOSTS; do iptables -A INPUT -i $IF_INT -s $SOURCE -p tcp --dport 445 -j ACCEPT iptables -A INPUT -i $IF_INT -s $SOURCE -p tcp --dport 139 -j ACCEPT iptables -A INPUT -i $IF_INT -s $SOURCE -p udp --dport 137 -j ACCEPT iptables -A INPUT -i $IF_INT -s $SOURCE -p udp --dport 138 -j ACCEPT done;

Add this to your existing iptables script and your good to go.

First method, run

#sudo -s -E

Second method, save all necessary variables in the current user (not root) shells profile (i.e. for bash its ~/.bashrc) and save these environment variables.

#vi ~/.bashrc export param1=value1 export param2=value2 #

That’s all to it.

Here we have a switch with a priority “1″ Switch#show switch

*1 Master 0023.344b.de80 1 0 Ready

We need to increase its priority number in order to force it to become the master when it joins the switch stack Switch#configure terminal Enter configuration commands, one per line. End with CNTL/Z. Switch(config)#switch 1 ? priority Set the priority of the specified switch provision Configure Switch provision / offline config renumber Renumber the specified switch number

Switch(config)#switch 1 priority 15 Changing the Switch Priority of Switch Number 1 to 15 Do you want to continue?[confirm] New Priority has been set successfully

For here, we can check the switch status and priority number set to “15″ Switch#sh switch Switch/Stack Mac Address : 0023.344b.de80 H/W Current

*1 Master 0023.344b.de80 15 0 Ready


When this stack is joined in a switch stack, it will elect itself as the switch master (check the Master LED after booting). Note that the switch stack can only handle only 9 stacked switches, so priority number 15 should be more than enough. Then the only problem if somebody set another switch with priority number 15 too, we will check on that later

We just bought some Cisco Wireless Access Point (model 1131AG) but unfortunately these are already in lightweight mode. In this mode, you would need a Wireless LAN Controller to utilize them. There a documentation to how to upgrade an autonomous Cisco Aironet Access Point to lightweight mode only a small section discusses the reversing the process. This blog discusses how I managed to brick errm reverse the process which is not recommended by Cisco.

1. Download the appropriate Cisco IOS from the cisco website (You need to have a valid Cisco account to do this ) For this I downloaded c1130-rcvk9w8-tar.124-10b.JA3

2. Install a TFTP Service (recommend SolarWinds free TFTP server)

3. Rename the image to c1130-k9w7-tar.default and place the image in the TFP source directory

4. Change to IP address of the TFTP Server to any IP address between 10.0.0.2 to 10.0.0.30 (I used 10.0.0.2 on my laptop where the TFTP service is running)

5. Connect the access point on the same switch where the TFTP service is connected. Note: Ensure there is no DHCP service running on the this device.

6. Press the mode button of the access point while pluggin in the power (wait for about 20-25 seconds). Wait for the one of the LED to turn RED (one them becomes Amber first) then release the mode button.

If everything goes well, the process will take around 10 to 15 minutes.

Here are the screenshots from the console of the access point, the sniffer on my laptop and the TFTP server activity.

On the final outcome, the access point can now operate in autonomous mode with a full fledge IOS that enables it to function in stand alone.

Enjoy!

For you guys to appreciate this, you should try doing this challenge manually from the Spanner. Then try watching the this video in order to appreciate how it is done with the Hackvertor. Enjoy!