IT Security & Network Engineering Knowledge Base

Practical documentation and technical guides on network security, firewalls, Linux systems, monitoring, and automation.
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F5 LTM – How do I perform software installations ?

Installation and upgrade of software on the F5 LTM is extremely straight forward.  Each image is installed onto a slot, the slot can then be upgraded or re-imaged. 1. Transfer Image Create a directory ‘[root@f5:Active] config # mkdir /shared/images/legacy’ Copy the iso image to the directory ‘/shared/images/legacy’ using scp. Move to the directory ‘[root@f5:Active] config … Read more

Juniper SRX – Site to Site VPN using a Dynamic IP address

Within this article we will look at the commands required for configuring a Site to Site VPN when one peer is using a dynamic IP address. Note : This article does not include the VPN configuration in its entirety only the additional/amended commands required for this scenario. There are 3 configuration settings that are defined. … Read more

Brocade ADX – NAT

Within this article we will look at the two ways in which to NAT traffic. Source NAT Pool This examples provides the commands required to configure source NAT via the use of a pool and ACL. This allows you to source NAT a number of internal hosts behind the ADX to a single IP address. … Read more

Juniper SRX – How to configure a policy based VPN

Below shows the necessary steps/commands to create a policy based VPN on a Juniper SRX series gateway. The main difference with a policy based VPN is that the tunnel action is defined within each security policy. Note : For troubleshooting steps please see here This VPN is configured with the following : Remote Endpoint : … Read more

Juniper SRX – Dynamic VPN

Within this tutorial we will be showing you how to configure Remote Access VPN (Dynamic VPN) on the Juniper SRX. IKE Configure Aggressive Mode set security ike policy ike-dyn-vpn-policy mode aggressive set security ike policy ike-dyn-vpn-policy proposal-set standard Define Preshared Key set security ike policy ike-dyn-vpn-policy pre-shared-key ascii-text <PRE-SHARED KEY> Configure the IKE Gateway Here … Read more

Juniper SRX – How to configure a route based VPN

Below shows the necessary steps/commands to create a route based VPN on a Juniper SRX series gateway. The main difference with a route based VPN is that a tunnel interface is created and assigned to your external interface. Any traffic that you wish to encrypt is routed to this tunnel interface. Access to and from … Read more

Juniper SRX – NAT

The Juniper SRX offers 3 main types of NAT. These are source, destination and static. In this article we will be providing explanations and configuration examples for each. Source NAT As the name suggests source NAT translates the source IP address. There are 2 main types of source NAT these are: Interface NAT – Traffic … Read more

Brocade ADX – CSW nested rules

Nested CSW rules provides the ability to perform Boolean (AND, OR etc) based conditions on standard csw rules. Within this example we will be : Redirecting any request that has a host header of ‘PRODUCTION.example.com’ and containing a URL request for /FOLDER/index.html to ‘/REDIRECT/index.html’ Balancing any request that has a host header of ‘STAGING.example.com’ and … Read more

How do I upgrade a Juniper SRX Series gateway

Within this tutorial we will be providing the steps required to upgrade your Juniper SRX firewall. Copy Image First of all we copy the image over to the SRX via the use of scp. In this case I have used putty’s pscp. C:\Windows\System32>pscp “C:\Users\admin\Downloads\junos-srxsme-11.4R1.6-domestic.tgz” root@[SRX IP]:/mfs Confirm Hash Next we confirm that the file is … Read more