CLI Commands for Troubleshooting Infoblox

With Infoblox you’re almost doing everything through the WebUI on the Infoblox Grid Master. At least the daily business such as adding/changing/deleting/moving/whatever DNS, DHCP, and IPAM stuff. Even troubleshooting is almost done through this HTTPS-based GUI. However, some circumstances require the use of the CLI on an Infoblox appliance/VM, called “Remote Console Access” aka SSH. … Continue reading CLI Commands for Troubleshooting Infoblox

NTP Appliance: Meinberg LANTIME & SyncFire

In case you’re responsible for an enterprise network or data center you should care about NTP. Refer to “Why should I run own NTP Servers?“. As a hobby technician you might first think about Raspberry Pis with self soldered GPS modules. Well, good idea to play with, but not reliable at all. Way to unstable, … Continue reading NTP Appliance: Meinberg LANTIME & SyncFire

Why should I run own NTP Servers?

… since we all can use “pool.ntp.org”? Easy answer: Many modern (security) techniques rely on accurate time. Certificate validation, two-factor authentication, backup auto-deletion, logs generation, and many more. Meanwhile, we use an unauthenticated protocol (via stateless UDP) from unauthenticated sources (NTP pool) to rely on! Really? If you are using a couple of different NTP … Continue reading Why should I run own NTP Servers?

My Network Gadgets

This post is not about software but hardware tools for network admins. Which network gadgets am I using during my daily business? At least three, namely the Airconsole, the Pockethernet and the ProfiShark, which help me in connecting to serial ports, testing basic network connectivity, and capturing packets in a high professional way. Come in … Continue reading My Network Gadgets

My CCNP TSHOOT Lab: The Overall Picture

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 … Continue reading My CCNP TSHOOT Lab: The Overall Picture

Dual-Stack EIGRP Lab

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 … Continue reading Dual-Stack EIGRP Lab

OSPFv3 with IPsec Authentication

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.

OSPFv2 Capture

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.

MP-BGP Capture

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 … Continue reading MP-BGP Capture

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

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

IPv6 Upper Layer Protocol Samples

Some time ago I published a pcap that can be used to study basic IPv6 protocol messages such as ICMPv6 for Router Advertisements, Neighbor Solicitations, etc.: “Basic IPv6 Messages: Wireshark Capture“. You can use it to learn the basic IPv6 address assignment and layer 2 address resolution. However, that pcap does not include any upper … Continue reading IPv6 Upper Layer Protocol Samples

FortiGate Out-of-Band Management

In some situations, you want to manage your firewall only from a dedicated management network and not through any of the data interfaces. For example, when you’re running an internal data center with no Internet access at all but your firewalls must still be able to get updates from the Internet. In those situations, you … Continue reading FortiGate Out-of-Band Management

True Random PSK Generator on a Raspi

In my previous blogpost I talked about the true random number generator (TRNG) within the Raspberry Pi. Now I am using it for a small online pre-shared key (PSK) generator at https://random.weberlab.de (IPv6-only) that you can use e.g. for site-to-site VPNs. Here are some details how I am reading the binary random data and how … Continue reading True Random PSK Generator on a Raspi

Playing with Randomness

Unpredictable random numbers are mandatory for cryptographic operations in many cases (ref). There are cryptographically secure pseudorandom number generators (CSPRNG) but the usage of a hardware random number generator (TRNG) is something I am especially interested in since many years. While there are many proprietary TRNGs (list) with different prices, I had a look at … Continue reading Playing with Randomness