IP Address Conflicts with VMware ESX and Cisco ASA
KB ID 0000635 Problem My colleague was setting up a DMZ server for one of our clients, it was a virtual server that was presented to the DMZ of a Cisco ASA 5510. Every time he gave it a static IP address it popped up an IP address conflict (no matter what the IP address was). Windows has detected an IP address conflict Another computer on this network has the same IP address as this computer. Contact your network administrator for...
Cisco ASA to Juniper SRX Site to Site VPN
KB ID 0000710 Problem You want to establish a site to site VPN from a site with a Cisco ASA firewall, to another site running a Juniper SRX firewall. I had to do this this week, and struggled to find any good information to help. In the example below I’m configuring the whole thing from a laptop (172.16.254.206) that’s on the Juniper’s site. Use the diagram below, and substitute your own IP addresses and subnet...
Cisco ASA 5500 Allowing Tracert
KB ID 0000753 Problem I’d always assumed that as Tracert uses ICMP, and that simply adding ICMP inspection on the ASA would let Tracert commands work. A client of mine is having some comms problems and wanted to test comms from his remote DR site, he had enabled time-exceeded and unreachable on the ASA (for inbound traffic) and that had worked. I checked the default inspection map and found inspect ICMP was there? As it turns...
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 – Find Out VPN Tunnel Uptime
KB ID 0000863 Problem I needed to get the Uptime/Duration of a particular VPN tunnel this week. It was for a client with multiple VPN tunnels that was having problems with just one. Solution Option 1 via Command Line 1. Connect to to the firewall > Go to enable mode and use the following command, replace 123.123.123.123 with the IP of your VPN endpoint. PetesASA> PetesASA> enable Password: ******** PetesASA# show...