Cisco ASA – DNS Doctoring
KB ID 0001113 Problem Cisco DNS doctoring is a process that intercepts a DNS response packet as it comes back into the network, and changes the IP address in the response. Why Would you want to do this? Well lets say you have a web server on your network, and its public IP is 111.111.111.111, and on your LAN its internal IP address is 192.168.1.100, its public DNS name, (or URL) is www.yoursite.com. When a user types www.yoursite.com...
Cisco ASA: Remove FTD and Return to ASA and ASDM
Remove FTD KB ID 0001496 Problem A few weeks ago I posted an article about re-image your Cisco ASA to FTD (FirePOWER Threat Defence). Now you may find the the FTD is not as ‘Feature rich’ as your old firewall, or that there’s a ‘Lack of feature parity’, which are two polite ways of saying that it’s crap, (sorry it’s just awful, as usual Cisco should’ve spent a LOT longer developing this...
Factory Reset a Cisco Firewall
KB ID 0000007 Problem You want to wipe the firewall’s config and revert to the factory settings (passwords blank – management or inside set to 192.168.1.1 and DHCP enabled, with all other settings wiped). Solution 1. Connect to the ASA via the console Cable. CLICK HERE 2. log in and go to configure terminal mode. 3. Execute the following command “config factory-default” 4. Press the space bar a few times to execute the...
Cisco ASA – Enable Split Tunnel for Remote Clients
KB ID 0000066 Problem This is a simple job to do from command line, however the world is full of people who would rather spend an hour in the ASDM working out how to do it! So I’ve included both methods. What is split tunneling? This is the process of letting a remote VPN user browse the web, and access local resources etc, from their location whilst connected to your VPN in this case via SSLVPN, but also from WebVPN or IPSEC...
Deploy Cisco ASA 55xx in Active / Standby Failover
KB ID 0000048 Problem You want to deploy 2 Cisco ASA 55xx Series firewalls in an Active/Standby failover configuration. Solution Assumptions. Hardware on both ASA firewalls is identical. The correct license’s for failover are installed on both firewalls. The same software versions are installed on both firewalls. You have your PRIMARY firewall set up and running correctly (Everything works!). In this example the firewalls were...
Cannot Access / Open ASDM
KB ID 0000458 Problem Out of the box Cisco PIX/ASA devices should have a working ASDM. This config can get broken over time, and also there are a few things that can trip you up on your client machine. Solution Make sure the client machine you are using is not the problem 1. The ASDM runs using Java make sure the machine has Java installed. Note: If you are using Java version 7 Update 51 see the following article. Unable to Access...
Convert ASA 5500-X To FirePOWER Threat Defence
KB ID 0001490 Problem I’m seeing more and more people asking questions in forums about FTD, so I thought it was about time I looked at it. Cisco ASA 5500-X firewalls can now be re-imaged to run the FTD software. The thinking is that the FTD will merge the Cisco ASA product and the FirePOWER product into one unified operating system. Then that is managed by FDM (FirePOWER Device Manager), basically a web management GUI. Solution...
Cisco ASA – Password Recovery / Reset
KB ID 0000572 Problem Note: This procedure allows you to reset the password WITHOUT LOSING THE CONFIG You need to access a Cisco ASA device and do not have the passwords, there can be lots of reasons for this, lack of good documentation, bought a second hand firewall, the last firewall admin never told anyone etc. This method does require physical access to the ASA, a console cable, and a machine running some terminal emulation...
ASDM on Windows 10: ‘Cannot find Javaw.exe?’
KB ID 0001478 Problem Windows 10 machine, (with Latest Java installed), while attempting to launch the ASDM you see; Windows cannot find ‘javaw.exe’. Make sure you typed the name correctly, and then try again. Solution I should have fixed this a lot quicker than I did, because the error message was a lot more descriptive in older versions of Windows and the ASDM! This is the same problem seen on Windows 8. You still need...
Cisco ASA – Allow Remote Management
KB ID 0000173 Problem Quite a while ago I wrote the “Connecting to and managing Cisco firewalls” article, which is still pretty complete, but I’ve been asked on a few occasions, “How do I actually configure the firewall to allow remote administration via, SSH, or HTTPS/ASDM, or Telnet If you have no network connection to the firewall, then you will need to connect via console cable (CLICK HERE). Solution...