We feature technical articles across the entire IT spectrum - Networking, security, operating systems, cloud, and programming.

How do I create a trunk port in ESX ?

In order to create a trunk port in ESX you need to : Within vSphere or ViClient go to the “Configuration” tab. Select “Networking“ Select your “Add Networking“. Choose “Virtual Machine” and click “Next“ Select your Virtual Switch (or create one), then click “Next“ Choose you Network label and then add the VLAN ID as … Read more

Linux: Password Protect & Encrypt File Using OpenSSL

In this article we will encrypt (using AES 256 cbc) and password protect (Salt the AES) a file using the openssl binary. The file we will encrypt will be the file secretfile.txt.As you can see it is just a plain text file. [root@linux tmp]# cat  secretfile.txt This is a secret file that we do not … Read more

IPSO Configuration Sets

IPSO configuration sets allow you to change (or save) your systems complete current configuration. Allowing you to choose the required configuration (set) of your firewall with a few simple commands. This is useful for importing in configurations from other devices rather then setting up a box from scratch. Configuration Set directory The active configuration file … Read more

Enabling RIP on a Netscreen

Routing Information Protocol (RIP) is a distance vector protocol used as an Interior Gateway Protocol (IGP) in moderate-sized autonomous systems (AS). Enabling RIP on a VR and an Interface set vrouter trust-vr router-id 10 set vrouter trust-vr protocol rip set vrouter trust-vr protocol rip enableset interface trust protocol rip enable Advertise the default route set … Read more

PIX / ASA – Display Encrypted Pre-Shared Keys.

To allow you to view your preshared keys on your PIX ASA use the command `more system:running-config`.  You can also view the preshared password with some versions of ASDM. Below shows the example of the command. pixfirewall# show run ! tunnel-group mytunnel type ipsec-rapre-shared-key * telnet timeout 5 Your preshared key ….. pixfirewall# more system:running-config! … Read more

Netscreen – AC-VPN

AC-VPN Auto-connect VPN works with a hub and spoke setup. Once static VPNs have been configured between all the spokes and the hubs, AC-VPN and NHRP (Next Hop Routing Protocol) is configured on each spoke and the hub.When traffic is initiated between 2 spokes the traffic is passed via the hub while a dynamic tunnel … Read more

Netscreen – VPN Topologies

Back to Back VPNs Back to Back VPNs allow you to create a tunnel for each spoke to the hub. The hub will then have a policy to allow traffic from one tunnel to the next. You can either place each tunnel within its own zone and create a policy between each of the zones. … Read more

Netscreen `set arp always-on-dest` command

By default, Netscreen (ScreenOS versions 6.0.0 or below) will cache the source MAC address from the initial packet for a new session. It will then use this MAC address for the return traffic. This can cause problems with external routers running VRRP where traffic is sent using a Virtual IP but a physical MAC address … Read more

Netscreen – Overview of basic Traffic Shaping

There are 3 main types of traffic shaping on the Netscreen firewalls. Interface Based traffic shaping. Bandwidth allocated shaping in policies. Priority based traffic shapping in policies. Policy Based Policing Bandwidth: Traffic beyond this threshold is dropped at the ingress side of the security device.Guaranteed Bandwidth: Traffic below this threshold will be passed with highest … Read more