16 articles Networking

Cisco inverse subnet masks

Leeched from http://www.cyberflunk.com/~nikm/cisco/masks.html (without permission) Cisco Netmasks, CIDR sizes, and Inverse Masks The address/netmask syntax of 172.16.35.0/255.255.255.0 should be familiar to anyone with some experience with IP routing, and is fairly easy to figure out address ranges given a calculator and a piece of scrap paper. There are other forms of addressing which are used…

How to redirect log files to another drive (Checkpoint) (Firewall NG)

I’m running VPN-1 UTM and this tricked worked fine. Looking at the registry, there are several keys under HKEY_LOCAL_MACHINE\SOFTWARE\CheckPoint\FW1\ which look to pertain to whichever version you have installed. Under the top level key HKEY_LOCAL_MACHINE\SOFTWARE\CheckPoint\FW1\ is a “CurrentVersion” String. Mine is “6.0” so I navigated to HKEY_LOCAL_MACHINE\SOFTWARE\CheckPoint\FW1\6.0 and created the “FWLOGDIR” string there, restarted the…

How do I create a VLAN?

*** NOTE: this was written several years ago – but may still be useful *** VLANS Increase security and ease administration and relocation. Break up broadcast domains. VLANS work at layer 2 and 3 of OSI model. Communication between VLANs uses layer 3 routing. 3 ways of assigning a switched port to VLANs: Port-Centric -…