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Cisco ASA Ping TCP troubleshooting command

Cisco ASA Ping TCP troubleshooting command

We’ve all used ping to test basic connectivity and we all know that command sends ICMP packets and waits for replies. On Cisco ASA’s you can also use an enhanced version of this command to send any TCP packet instead of just ICMP. This is awesome for troubleshooting purposes and verifying remote services/ports are up, running and reachable. It’s also a great trick to force traffic over a VPN connection to bring a tunnel up from the ASA! Let’s assume…

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Cisco ASA Active/Active Failover

Cisco ASA Active/Active Failover

Cisco ASA Active/Active failover requires two identical Cisco ASA appliances talking to each other through a dedicated failover link and a dedicated stateful link (these can be the same interface). With Active/Active failover both appliances will carry traffic. Failover contexts and failover groups need to be created, the failover group is then applied to the Primary or Secondary ASA appliance. Example configuration parameters:ASA1 & ASA2 are the firewall names being used. Make sure the interfaces being used for the failover…

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Cisco ASA Active/Standby Failover

Cisco ASA Active/Standby Failover

Active/Standby failover enables you to use a standby ASA to take over for a failed unit. When the active unit fails it changes to the standby state while the standby unit changes to the active state. The unit that becomes active assumes the IP addresses and the MAC addresses of the failed unit and starts passing traffic. In Active/Standby failover, failover occurs on a unit basis, even on systems running in multiple context mode, you can’t failover individual contexts. Aside…

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FortiGate as a DNS slave to a Windows AD DNS Master v5.4

FortiGate as a DNS slave to a Windows AD DNS Master v5.4

This post goes over how to setup a FortiGate firewall as a slave DNS server to a Windows DNS master.  This is a great feature to enable for branch offices or even as basic redundancy to a single Windows DNS server. Starting on the Windows DNS Server: Launch DNS Manager Double click on the zone you want to replicate and locate the SOA record and edit it. Go to the Zone Transfer tab and enable zone transfers.  You can leave…

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FortiGate WAN Link Monitor v5.4

FortiGate WAN Link Monitor v5.4

You’ve setup your FortiGate and have multiple Internet providers.  You are using basic failover for your providers, you want to monitor the links to automate the failover but you don’t want to setup SD-WAN or WAN LLB. What you want is link-monitor, or what used to be called ping server detect. With link-monitor setup, when the target detects a failure the routes for WAN1 will be deleted and traffic will go to WAN2.  When the target detects success the routes…

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Cisco Site to Site GRE VPN Tunnel with EIGRP

Cisco Site to Site GRE VPN Tunnel with EIGRP

What is a GRE tunnel? Generic Routing Encapsulation (GRE) is a tunneling protocol that lets you run a routing protocol between endpoints. This example will create a GRE tunnel between two routers and will run EIGRP between the two. Topology Summary: 192.168.13.0/24 will be the Tunnel Network IP block  Router-1 lo0 10.1.1.0/24 e0/0 192.1.12.2 Router-2 lo0 10.2.2.0/24 e0/0 192.1.23.2 Router-1 interface tunnel1 ip address 192.168.13.1 255.255.255.0 tunnel source 192.1.12.1 tunnel destination 192.1.23.3 router eigrp 100 no auto-summ net 192.168.13.0 net…

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Cisco IOS Site to Site VPN

Cisco IOS Site to Site VPN

Five steps to configuring an IPSec Site to Site VPN! Configure Phase I – ISAKMP Parameters Configure Phase II – ESP Parameters Configure the interesting traffic ACL Link the above parameters to each other using a Crypto Map Apply the Crpyto Map to the outbound interface Notes: Items below between < > are meant to be replaced with a value Phase 1 parameters: pre shared key: cisco123 Peer IP:  192.1.23.3 Phase 1 encryption:  3des Phase 1 hash:  md5 Phase 1…

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FortiGate SSL VPN Internal DNS Resolution v5.4

FortiGate SSL VPN Internal DNS Resolution v5.4

You’ve setup your FortiGate firewall, configured SSL VPN and deployed your clients.  Your users can log in but they need to use fully qualified domain names to resolve hosts internally. To create a better user experience, you want to append your DNS domain name to your SSL VPN users when they connect, just like when they are in the office.  It’s pretty straight forward assuming you already have SSL VPN configured, if you don’t follow this guide: FortiGate SSL VPN…

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FortiGate Agent Based FSSO AD Integration v5.4

FortiGate Agent Based FSSO AD Integration v5.4

If you want to report on user Internet usage and possibly even define access rules based on your Active Directory groups this document is for you.  We’ll install the FSSO Collector Agent in basic mode, identify the groups we are interested in and setup the FortiGate. The FSSO Collector will monitor the Windows security logs on your domain controller for log on and log off events, these events contain the IP address of the computer that logged on or off…

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Cisco FirePOWER DNS Security Intelligence Policy v6

Cisco FirePOWER DNS Security Intelligence Policy v6

DNS-based Security Intelligence allows you to use your FirePOWER implementation to blacklist traffic based on the domain name lookup requested by a client workstation. What’s cool is that items configured here are blocked BEFORE access control rules so you can block bad traffic without wasting resources inspection it further based on the work Cisco has already done, and continues to do via the Cisco Talos Security Intelligence and Research Group.  These lists we’ll select below are automatically updated as Cisco…

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FortiGate Managed Access Point Tunnel Mode v5.4

FortiGate Managed Access Point Tunnel Mode v5.4

This example will use a FortiGate firewall to manage FortiAP access points.  We’ll create what’s called a tunnel-mode wireless network, which means the wireless clients will be on a different network then the wired clients.  The FortiGate firewall will also provide DHCP services to both wired and wireless clients. Creating the wireless network Pick an interface that will have the AP connected to it, this can be on the local FortiGate or a local FortiGate port that’s connected to a…

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FortiGate Managed Access Point Bridge Mode v5.4

FortiGate Managed Access Point Bridge Mode v5.4

This example will use a FortiGate firewall to manage FortiAP access points.  We’ll create what’s called a bridge-mode wireless network, which means the wireless clients will be on the same network as the wired clients.  The FortiGate firewall will also provide DHCP services to both wired and wireless clients. I’ll assume you already have an outbound policy created to allow traffic from inside your network out to the Internet.  Because in this example the wired and wireless traffic will be…

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FortiGate Periodically Dropping Comcast Connection v5.4

FortiGate Periodically Dropping Comcast Connection v5.4

This quick post is to document an issue we’ve seen enough times to make this change part of our standard deployment. Issue:  New FortiGate installation seems to drop Comcast Internet connection for a minute periodically. This isn’t a link monitor issue or anything complex.  The problem comes down to some Comcast modems, other providers I’m sure have a similar issue. When a FortiGate is deployed, the FortiGaurd service uses port 53 for updates.  When these impacted modems see non DNS…

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FortiGate Category Filtering Office 365 Issue v5.4

FortiGate Category Filtering Office 365 Issue v5.4

Content filtering is a great feature with the FortiGate firewalls but the nature of what’s happening behind the scenes means some web sites do not like to be inspected and some users don’t fit the standard policy. For example, if you enable blocking unrated categories with your web filtering, and you have Office 365 there’s a good chance your users will start getting errors with Office 365.  A bit of tweaking fixes this, but it would be better to know…

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FortiGate Geo Blocking v5.4

FortiGate Geo Blocking v5.4

I’m frequently asked to block users from accessing certain countries and it can help prevent exploits if your users have no business connecting to some of these countries.  This is called Geo Blocking and it’s pretty easy to setup. Setup address object for the country you want to block Navigate to Policy & Objects > Addresses and click Create New Address Enter the name of the country in question Change the Type to Geography Change the Country to the country…

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