Cisco FirePOWER is Blocking an Application
KB ID 0001286 Problem A few weeks ago I installed a 5525-X firewall for a client, and set it up as follows; ASA Setup FirePOWER Services (for ASDM) And all was well, then a week later I got an email… One of our teachers is doing a project with MATHS and ICT involving bitcoin. Basically, he has something called BITCOIN CORE WALLET installed and it used to work with the old Firewall. I’ve installed it on my work laptop and taken...
Troubleshooting Phase 1 Cisco Site to Site (L2L) VPN Tunnels
KB ID 0000216 Problem Site to Site VPN’s either work faultlessly straight away, or involve head scratching and a call to Cisco TAC, or someone like me to come and take a look. If I’m honest, the simplest and best answer to the problem is “Remove the Tunnel from both ends and put it back again”. Just about every VPN tunnel I’ve put in that did not work, was a result of my fat fingers putting in the wrong...
Cisco ASA – Using ‘logging’ to see what ports are being blocked
KB ID 0000702 Problem If you look after a firewall, sooner or later something will fail, and the blame (rightly or wrongly), will be leveled at the firewall. I came back from holiday this week to find a client had got a problem with secure POP email. The problem had been fixed (temporarily) by dropping the affected users into a group, and opening all ports. As this had fixed the problem then it’s fair to say that the ASA was...
Cisco ASA 5500 – Configuring PPPoE
KB ID 0000831 Problem Until very recently I’d never had to configure PPPoE. Most of my clients in that sort of connection speed range have ADSL with a router provided by their ISP. A Router that connects via PPPoA usually. Here in the UK the main ISP’s (BT and Virgin) are busy rolling out FTTC connections that terminate with a ‘modem’ that presents an RJ45 socket. So without the need for a router, you can get...
Cisco ASA – I Cannot Ping External Addresses? (Troubleshooting ICMP)
KB ID 0000914 Problem Considering we use ICMP to test connectivity, the fact that it is not a stateful protocol can be a major pain! Last week one of my colleagues rang me up and said, “Can you jump on this firewall, I’ve got no comms, and I cant ping external IP addresses. I can ping the internet from the firewall and I can ping internal IP addresses form the firewall”. Solution 1. Before we start, lets get the basics...