Es war mal wieder Zeit für ein bisschen Bastelarbeit an meinem Dauerprojekt ADS-B. Letztes Jahr hatte ich zunächst eine DIY-Antenne und schließlich eine bei eBay gekaufte Antenne für den Empfang der Flugzeugdaten gebastelt und getestet. Dieses Mal war der DVB-T Stick an der Reihe, der durch den “FlightAware Pro Stick” ersetzt wurde, welcher über einen eingebauten Vorverstärker in der entsprechenden Frequenz verfügt. Zusätzlich habe ich noch den ebenfalls von FlightAware hergestellten Mode-S 1090 MHz Bandpass Filter für ADS-B mit eingebaut, welcher für weniger Rauschen im Frequenzbereich drum herum sorgt.
Beides zusammen hat ein weiteres Mal für einen erheblich besseren Empfang bei gleicher Antenne und Position gesorgt. Das schöne an der Sache: Der Stick hat direkt und ohne irgendeine Konfiguration funktioniert, da er ebenfalls als normaler DVB-T Stick von Linux und von der verwendeten dump1090 Software erkannt wurde.
Continue reading ADS-B Empfangsbereich mit dem FlightAware Pro Stick erweitern
I want to talk about a fun fact concerning my blog statistics: Since a few years I have some “CLI troubleshooting commands” posts on my blog – one for the Palo Alto Networks firewall and another for the FortiGate firewall from Fortinet. If you are searching on Google for something like “palo alto cli commands” or “fortigate troubleshooting cli” my blog is always listed amongst the first 2-4 results.
But for some reasons the article for Fortinet has much more hits. I don’t know why but I have two different ideas. What do you think?
Continue reading Palo vs. Forti: Blog Stats
Since PAN-OS version 6.1 the Palo Alto Networks firewall supports LACP, the Link Aggregation Control Protocol which bundles physical links to a logical channel. Palo Alto calls it “Aggregate Interface Group” while Cisco calls it EtherChannel or Channel Group. I configured LACP for two ports connected from a Palo Alto firewall to a Cisco switch. Following are the configuration steps for both devices as well as some show commands.
Continue reading Palo Alto Aggregate Interface w/ LACP
I just configured LLDP, the Link Layer Discovery Protocol, on a Palo Alto Networks firewall. What I really like about those firewalls is the completeness of configuration capabilities while the possibility to use it easily. Everything can be done via the GUI, even the view of neighbors/peers. Per default, only a few TLVs are sent by the Palo, but this can be extended by using LLDP profiles.
Following are a few configuration screenshots from the Palo as well as the config and show commands from a Cisco switch.
Continue reading Palo Alto LLDP Neighbors
A few weeks ago I published a pcap file along with many challenges in order to invite anyone to download and to solve it. Though there are not that many answers posted in the comment section I hope that the trace file will help many people understanding the layer 2/3 protocols or to work with it during CCNP exam preparation.
Following are my answers to the 46 challenges I posted back then. I’ll not only give you the mere results but many Wireshark screenshots with some notes on how to get them. Here we go:
Continue reading Wireshark Layer 2-3 pcap Challenge Answers
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 once required for the current scenario. Kind of a template. Of course with IPv6 and legacy IP.
Continue reading Basic Cisco Configuration
Second post of this little series. While I was using my CCNP SWITCH lab for testing many different protocols, I “showed” and saved the output of those protocols as well. Refer to the lab overview of my last post in order to understand those outputs.
I basically saved them as a reference for myself in case I am interested in the information revealed by them. I won’t explain any details of the protocols nor the outputs here. Just many listings. Fly over them and reflect yourself whether you would understand anything. ;) Here we go:
Continue reading CCNP SWITCH Lab show commands
While preparing for my CCNP SWITCH exam I built a laboratory with 4 switches, 3 routers and 2 workstations in order to test almost all layer 2/3 protocols that are related to network management traffic. And because “PCAP or it didn’t happen” I captured 22 of these protocols to further investigate them with Wireshark. Oh oh, I remember the good old times where I merely used unmanaged layer 2 switches. ;)
In this blogpost I am publishing the captured pcap file with all of these 22 protocols. I am further listing 46 CHALLENGES as an exercise for the reader. Feel free to download the pcap and to test your protocol skills with Wireshark! Use the comment section below for posting your answers.
Of course I am running my lab fully dual-stacked, i.e., with IPv6 and legacy IP. On some switches the SDM template must be changed to be IPv6 capable such as
sdm prefer dual-ipv4-and-ipv6 default .
Continue reading Wireshark Layer 2-3 pcap Analysis w/ Challenges (CCNP SWITCH)
If you are using a Lastline device (Manager, Engine, Sensor or Pinbox) you can reach the machine via SSH after you activated it via
monitoring_user_password . However, per default this uses only a password for authentication. If you want to use the key-based authentication for this “monitoring” user account you can add the public key to the authorized_keys file for that user.
This is a small record on how to add a public key to the Lastline device. However, it is quite general since the Lastline appliance is built upon a standard Ubuntu server.
Continue reading Lastline SSH Key-Based Authentication for “monitoring” User
This is just a small post on how to enable SNMP on a Lastline Advanced Malware Protection appliance in order to query the basic host and network MIBs from an SNMP monitoring server. Note that this is not the preferred method of monitoring a Lastline device. The Product API (PAPI) should be used instead such as shown in the online docs. However, basic SNMP gives access to the CPU, memory, load average and the network interface statistics incl. the anonymous VPN tunnel interface.
Since all Lastline devices are basically a Ubuntu server, the basic setup for SNMP is quite similar to my tutorial for a generic Linux. The only step missing there is the allow statement for the Uncomplicated Firewall (ufw).
Continue reading Lastline SNMP Monitoring
I migrated an old Juniper SSG ScreenOS firewall to a Palo Alto Networks firewall. While almost everything worked great with the Palo (of course with much more functionalities) I came across one case in which a connection did NOT work due to a bug on the Palo side. I investigated this bug with the support team from Palo Alto Networks and it turned out that it “works as designed”. Hm, I was not happy with this since I still don’t understand the design principle behind it.
However, it was a specific and not business critical case: One Palo Alto firewall with two ISP connections using a destination network address translation (DNAT, an old IPv4 problem) and policy based forwarding (PBF) with the same destination ports. Following are some more details:
Continue reading Palo Alto PBF Problem
This is a cool and easy to use (security) feature from Palo Alto Networks firewalls: The External Dynamic Lists which can be used with some (free) 3rd party IP lists to block malicious incoming IP connections. In my case I am using two free IP lists to deny any connection from these sources coming into my network/DMZ. I am showing the configuration of such lists on the Palo Alto as well as some stats about it.
Continue reading Palo Alto External Dynamic IP Lists