Archives for 2021

Elastic-Stack for network engineers (Initial setup)

Switching from traditional log monitoring to Elastic-Stack is like switching from a horse-drawn carriage to the Falcon 9 rocket. Join the journey!

Cisco SSM On-Prem Upgrade procedure

This is another blog post for Cisco SSM On-Prem server where I'm showing the upgrade process.

Cisco ISE admin password lifecycle and reset

Quick notes about Cisco Identity Services Engine password lifetime and admin password reset.

Cisco SSM On-Prem password recovery procedure

For a Cisco Smart Software Manager Test Drive installation I used the older version 8-202010 and I wanted to perform an upgrade to the latest version 8-202108. And of course it is a test drive, I did not save or wrote down the password :). In this document I'm describing how to perform a password recovery for a Cisco SSM On-Prem installation.

Upgrading Netbox to Version 3.0

Yesterday, the version v3.0 of Netbox was released. Modernized WebUI and Off-canvas sidebar. My first impression: Version v3.0 is awesome! Note: Version v3.0.1 was released on 2021-09-01.

Gitlab AD-LDAP Integration

In this blog post I'm showing how to integrate GitLab Server with a Samba-based Active Directory.

Troubleshooting SFP transceivers and Packet captures

In an older blog post I was writing about "Useful Cisco Commands for Troubleshooting cable problems". In this blog post I'm showing an additional, useful commands for Fiber Optics troubleshooting and packet capturing on Cisco switches.

Cisco WLC - No secured WebUI after failover switching

Cisco WLC 3504 secured WebUI is not working on Secondary Unit in a failover (SSO) setup. When switched back to the Primary Unit, the secured WebUI is working again. Troubleshooting and solution of this strange behavior.

Some security settings for Apache Web Server

I'm showing in this blog post some security settings for the Apache web server including disabling of Directory Browsing, Server Signature and Server Token.

Integration of Nextbox UI Topology Viewer in Netbox

In this blog post I'm showing how to integrate NextBox UI Plugin into my Netbox installation. NextBox UI Plugin is a topology visualization plugin which is based on Cisco's neXt toolkit.

City of Erbach is ending their partnership with Odenwald gegen rechts

City of Erbach is ending their partnership with "Odenwald gegen rechts" ("Odenwald against Right")

WiFicalypse 2021

WiFicalypse 2021, FragAttacks. Design and Implementation flaws in WiFi.

Small Python script to quick test DMARCDKIM and SPF records

For a given occasion I wrote Small Python script to test a domain for DMARC, DKIM and SPF records. Those records are managed in a DNS Zone and are typically used in Anti-SPAM techniques.

Netbox Active Directory/LDAP Integration

In my newest blog post I show how to setup Netbox with Active Directory as backend for users and groups.

Concept for DNS security with Bind9, Pi-hole and OpenDNS

This is my new concept for DNS security with Bind9, Pi-hole and OpenDNS in my network. Bind9 is used as Enterprise DNS to resolve hostnames and IP addresses in the local area network, Pi-hole and OpenDNS are used for Internet DNS traffic. DNS traffic is passed by Cisco ASA Firewall ACL.

Blocking of Google Chrome FLoC

Blocking of Google Chrome FLoC (Federated Learning of Cohorts) on my web server

Weeks of the data leaks

Weeks of the data leaks and my approach after data leaks or breaches

Debian Unattended upgrades

Automatically install security-related upgrades on Debian Linux with unattended-upgrades

Fritzbox rack mounted

Fritzbox rack mounted on a 19" shelf and it's hardware issues: white description on a white box, no LED on ports for activity, height unit issues, Square wood and Velcro to fix ;)

Check in of configuration files to a Gitlab server

This is the third part of a series of blog posts about Cisco configuration backup with Netbox and Gitlab. This blog post covers the check in of configuration files to a Gitlab server

Low Level Device functions for backup with Netbox and Gitlab

This is the second part of a series of blog posts about Cisco configuration backup with Netbox and Gitlab. This blog post covers the low level functions to connect to network devices with pexpect.

Cisco configuration backup with Netbox and Gitlab

This is the first part of a series of blog posts about Cisco configuration backup with Netbox and Gitlab. It covers the connection to the Netbox API and to get the data of network devices with the pynetbox filter function.

Fritzbox on redundant ASA Firewall

Setup of two redundant Cisco ASA firewalls on a Fritzbox cable modem with Non-routed transfer network to keep the "PC-MAC"/"exposed host" configuration on Fritzbox during ASA failover switching

Cisco Smart Software Manager Test Drive

Cisco Smart Software Manager (SSM) On-Prem Test Drive installation, Virtual Machine setup and first steps in the Web UI