Cisco ASA 5500 – Adding New ‘Different Range’ Public IP Addresses
KB ID 0001006 Problem I got an email at work yesterday; “Hello Pete I have asked our ISP to give us two additional real IP addresses so that we can progress the following two projects: Microsoft DirectAccess Publishing documents to a web server from our internal DMS. {ISP Name} have come back and said that they don’t have the next available numbers in our current IP address range, but they do have two other numbers we could...
Configure Your Firewall for SNMP
KB ID 0001034 Problem Had a requirement to let SNMP traffic though a firewall this week, I have a client that has both SolarWinds and SCOM, and they need to monitor the external Citrix ADC load balancers. For SNMP we simply need UDP ports 161 and 162 (See below) but SolarWinds maintains ‘ping’ connectivity to the monitored assets, so ICMP also needs to be open. Inbound Ports Outbound Ports Solution As my ‘weapon of...
Cisco ASA – ‘access-group’ Warning
KB ID 0001035 Problem I’ve been writing Cisco ASA walkthroughs for years, and littered all over PeteNetLive you will see me warning readers every time I use access-group commands. So I’ve finally got round to putting this article up so I can reference it in future. What is an Access-Group command? You use an access-group command to apply an access-list to an interface, in a particular direction (in or out). Although I...
Cisco ASA – Policy NAT
KB ID 0001042 Problem I’ve been working on a large firewall deployment for a client, each of their DMZ’s have both a production and a management network. nothing particularly strange about that, but each of their DMZ’s has its own firewalled management network and it’s routable from the LAN. So If I’m an admin and I want to talk to a Linux appliance in their DMZ via its management interface, my traffic...
Cisco ASA – ‘Prove it’s Not The Firewall!’
KB ID 0001049 Problem Yeah, it’s funny because it’s true! The article title might not sound like the most professional approach, but when the ‘Well it’s not working now’ finger gets pointed at the ‘firewall guy/girl’, they need to ascertain two things; 1. Is the problem actually the firewall, if not then help the frustrated party track down the actual problem. 2. If your problem IS the...