Cisco ASA Domain Authentication and Trust (Allowing)
May08

Cisco ASA Domain Authentication and Trust (Allowing)

ASA Domain Authentication KB ID 0000973  Problem I cringed this morning when I was asked about this, last time I had to get a client to authenticate to a domain through a firewall, it was ‘entertaining’. The problem is Windows loves to use RPC, which likes to use random ports, so to make it work you either had to open TCP ports 49152 and 65535 (Yes I’m Serious). Or you had to registry hack all your domain controllers...

Read More
Fortigate: Cannot Ping an Interface?
Nov25

Fortigate: Cannot Ping an Interface?

KB ID 0001718 Problem With other firewall vendors (i.e. Cisco) you can ping any interface you are ‘directly connected to’. With Fortigate however you cannot (by default). That’s not the end of the world you can check connectivity using ARP (see below) which is what really cool network techs do instead! But if you want to be able to ping an interface (even for a short period of time). Here’s how to do it....

Read More
Windows Adding Firewall Rules With PowerShell
Apr24

Windows Adding Firewall Rules With PowerShell

KB ID 0001538 Problem There was a question on Experts Exchange this morning, the asker wanted to be able to add a ‘Trusted’ network range to their Windows Server Firewall settings as a ‘allow all ports’ rule. Solution You can of course add this manually in the GUI, normally I’d simply Add a Firewall Rule with a Group Policy. but the problem with that is, that’s fine if you want to open a particular...

Read More
Cisco Firewalls and PING
Aug01

Cisco Firewalls and PING

KB ID 0000351 Problem With regards to Ping, out of the box a Cisco firewall will allow you to ping the interface you are connected to, so in a normal setup inside clients can ping the inside interface, and the firewalls outside interface can be pinged from outside. OK – to understand pinging through a Cisco Firewall you need to understand that Ping is part of the ICMP protocol suite, and unlike other protocols is not “connection...

Read More
Cisco ASA 5500 Allowing Tracert
Nov17

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...

Read More