Tag Archives: Cisco Router

Protocol Independent Multicast (PIM) Capture

Routing, , , , , , , , , , ,

You never stop learning. One topic that hadn’t crossed my path in the past decade is: Multicast. Whew. Alongside all the technical literature, online presentations, and various blog posts, I decided to approach it the classic way – through packet captures. ;)

So here’s a new part of the #UltimatePCAP, which contains quite a bit of PIM traffic, including Hello, Join/Prune, Register (via unicast!), and more. Of course, for IPv6 and legacy IP (IPv4). Let’s have a look:

Continue reading Protocol Independent Multicast (PIM) Capture →

Palo Alto GRE Tunnel

Network, Palo Alto Networks, , ,

Since PAN-OS version 9.0 you can configure GRE tunnels on a Palo Alto Networks firewall. Greetings from the clouds. As always, this is done solely through the GUI while you can use some CLI commands to test the tunnel. This time Palo put a little stumbling block in there as you have to allow a GRE connection with a certain zone/IP reference. I will show how to set up such a GRE tunnel between a Palo and a Cisco router. Here we go:

Continue reading Palo Alto GRE Tunnel →

Workaround for Not Using a Palo Alto with a 6in4 Tunnel

Cisco Systems, IPv6, Palo Alto Networks, , , , , ,

Of course, you should use dual-stack networks for almost everything on the Internet. Or even better: IPv6-only with DNS64/NAT64 and so on. ;) Unfortunately, still not every site has native IPv6 support. However, we can simply use the IPv6 Tunnel Broker from Hurricane Electric to overcome this time-based issue.

Well, wait… Not when using a Palo Alto Networks firewall which lacks 6in4 tunnel support. Sigh. Here’s my workaround:

Continue reading Workaround for Not Using a Palo Alto with a 6in4 Tunnel →

My IPv6/Routing/Cisco Lab Rack (2019)

Memorandum, Off-Topic, , , , , , , , , , , , , ,

My lab rack of 2019 consists of multiple Cisco routers and switches, as well as Juniper ScreenOS firewalls for routing purposes, a Palo Alto Networks firewall, a Juniper SRX firewall, a server for virtualization and some Raspberry Pis. That is: This rack can be used for basic Cisco courses such as CCNA or CCNP, or for even bigger BGP/OSPF or IPsec VPN scenarios since those ScreenOS firewalls are perfect routers as well. Of course, everything is IPv6 capable. Having some PoE-powered Raspberry Pis you can simulate basic client-server connections. A Juniper SA-2500 (aka Pulse Connect Secure) for remote accessing the Lab rounds things up.

I am just writing down a few thoughts on why I have “designed” the rack in that way. It’s basically a reminder for myself. ;)

Continue reading My IPv6/Routing/Cisco Lab Rack (2019) →

My CCNP TSHOOT Lab: The Overall Picture

Cisco Systems, IPv6, Routing, , , , , , , , , , , , , ,

During the last few weeks I published a couple of blogposts concerning routing protocols such as BGP, OSPFv3, and EIGRP. (Use the “Cisco Router” tag on my blog to list all of them.) They are all part of my current Cisco lab that I am using for my CCNP TSHOOT exam preparation. While I depicted only the details of the routing protocols in those blogposts, I am showing my overall lab with all of its Cisco IOS configs here. Just to have the complete picture. There are a couple of not-yet-blogged configs such as VRRP, GLBP, NTP authentication, embedded event manager (EEM), or route-maps and distribute/prefix lists though.

Continue reading My CCNP TSHOOT Lab: The Overall Picture →

EIGRP Capture

Cisco Systems, IPv6, Routing, , , , , , , , ,

And again: Here comes a pcapng capture taken for the dynamic routing protocol EIGRP. If you want to dig into EIGRP messages, download the trace file and browse around it with Wireshark. Since I used both Internet Protocols (IPv6 and legacy IP), MD5 authentication, route redistribution, etc., you can find many different messages in it.

Continue reading EIGRP Capture →

Dual-Stack EIGRP Lab

Authentication, Cisco Systems, IPv6, Routing, , , , , , , , ,

Yet another routing protocol I played with in my lab. ;) This time: EIGRP, Enhanced Interior Gateway Routing Protocol, the proprietary distance-vector routing protocol developed by Cisco, which is now public available (RFC 7868). However, no third-party products in here but only Cisco routers. I am using named EIGRP for both Internet Protocols, IPv6 and legacy IP, along with MD5 authentication and redistribution from OSPF.

Continue reading Dual-Stack EIGRP Lab →

OSPFv3 with IPsec Authentication

Authentication, Cisco Systems, IPsec/VPN, IPv6, Routing, , , , , , , , , , , , , ,

Here comes a small lab consisting of three Cisco routers in which I used OSPFv3 for IPv6 with IPsec authentication. I am listing the configuration commands and some show commands. Furthermore, I am publishing a pcapng file so that you can have a look at it with Wireshark by yourself.

Continue reading OSPFv3 with IPsec Authentication →

OSPFv2 Capture

Authentication, Cisco Systems, Routing, , , , , , , , ,

I already had an OSPFv2 for IPv4 lab on my blog. However, I missed capturing a pcap file in order to publish it. So, here it is. Feel free to have a look at another small lab with three Cisco routers and OSPFv2. Just another pcapng file to practise some protocol and Wireshark skills.

Continue reading OSPFv2 Capture →

MP-BGP Capture

IPv6, Routing, , , , , , , , , , , , ,

For those who are interested in analyzing basic BGP messages: I have a trace file for you. ;) It consists of two session establishments as I cleared the complete BGP session on two involved routers for it. Refer to my previous blog post for details about the lab, that is: MP-BGP with IPv6 and legacy IP, neighbouring via both protocols as well, with and without password. The involved routers were 2x Cisco routers, one Palo Alto Networks firewall, and one Fortinet FortiGate firewall.

Continue reading MP-BGP Capture →

Basic MP-BGP Lab: Cisco Router, Palo Alto, Fortinet

Authentication, Cisco Systems, Fortinet, IPv6, Palo Alto Networks, Routing, , , , , , , , , , , , ,

While playing around in my lab learning BGP I configured iBGP with Multiprotocol Extensions (exchanging routing information for IPv6 and legacy IP) between two Cisco routers, a Palo Alto Networks firewall, and a Fortinet FortiGate firewall. Following are all configuration steps from their GUI (Palo) as well as their CLIs (Cisco, Fortinet). It’s just a “basic” lab because I did not configure any possible parameter such as local preference or MED but left almost all to its defaults, except neighboring from loopbacks, password authentication and next-hop-self.

Continue reading Basic MP-BGP Lab: Cisco Router, Palo Alto, Fortinet →

Generating SSHFP Records Remotely

DNS/DNSSEC, Linux, Security, SSH, Tutorial/Howto, , , , , , , , , , , , ,

Until now I generated all SSHFP resource records on the SSH destination server itself via ssh-keygen -r <name>. This is quite easy when you already have an SSH connection to a standard Linux system. But when connecting to third-party products such as routers, firewalls, whatever appliances, you don’t have this option. Hence I searched and found a way to generate SSHFP resource records remotely. Here we go:

Continue reading Generating SSHFP Records Remotely →

Basic Cisco Configuration

Cisco Systems, Design/Policy, Template, , , , , , , , , , , , , , , , ,

Following is a list of the most common Cisco device configuration commands that I am using when setting up a router or switch from scratch, such as hostname, username, logging, vty access, ntp, snmp, syslog. For a router, I am also listing some basic layer 3 interface commands, while for a switch I am listing STP and VTP examples as well as the interface settings for access and trunk ports.

This is not a detailed best practice list which can be used completely without thinking about it, but a list with the most common configurations from which to pick out the ones required for the current scenario. Kind of a template. Of course with IPv6 and legacy IP.

Continue reading Basic Cisco Configuration →