Networking on Network Haven

Cisco ignore startup configuration

Sat, 16 May 2026 12:00:00 +0200

The startup configuration can be bypassed by booting into ROMMON or during normal operation. In either case, a reboot is required.

This is particularly useful, for example, if you need to perform a password recovery because you have forgotten your password, or for troubleshooting purposes.

Configuration in IOS

Switch# configure terminal
! to activate
Switch(config)# system ignore startup-config

! to deactivate
Switch(config)# no system ignore startup-config

Configuration in ROMMON

In the background, the IOS command simply sets the ROMMON variable SWITCH_IGNORE_STARTUP_CONFIG to 1 or 0 which we can also do manually.

Fixing SCEP Certificate Enrollment over HTTPS on eLux Thin Clients

Wed, 13 May 2026 12:00:00 +0200

Currently we trying out eLux as an replacement of older thin clients with ThinOS or IgelOS. We tried to configure 802.1x authentication and the therefore needed certificate enrollment with our current SCEP/NDES server. We came across the issue that the scep client that eLux uses – sscep – an open source “Simple SCEP client for Unix” doesn’t support certificates requests over HTTPS.

When investigating the problem we found this GitHub issue which explains our problem. Our NDES server was only reachable over HTTPS – both on the administration page and most importantly also on the request web page (certsrv/mscep) where the client requests their certificates.

Issue detecting domain network on domain controller when using NIC teaming

Fri, 10 Apr 2026 23:10:03 +0200

We had an issue where our domain controller lost its domain network profile after a reboot. When it came back up it was set to public instead of domain.

The problem occurred only when Windows NIC teaming (switch-independent) was used in combination with two network adapters in the team. As soon as one network adapter was disabled from the team (while the other remained active), the network profile (domain) was recognized correctly.

SNMP monitoring with Grafana, Prometheus and snmp_exporter

Sun, 22 Feb 2026 23:10:03 +0200

SNMP monitoring with grafana and prometheus can be done with the official snmp_exporter from prometheus.
Since I didn’t found any direct forward documentation, blog or any source of documentation in an ELI5 style how this will work, this is my try to document my findings and understanding on how this stuff works. To be honest I still don’t understand all stuff inside the generator configuration file but here is what I found out.

MikroTik SFTP backup script

Sun, 04 Jan 2026 23:10:03 +0200

Automated backups for MikroTik devices can be accomplished by running a scheduled script. The following script can be run in the scheduler in order to automate the backups to an SFTP share. It was tested on a MiroTik hEX RB750Gr3 with RouterOS 7.20.1. Just make sure to adjust the first five variables to your needs. This script is based on another script I found on the forum – here. I adjusted the date settings in the filename since these weren’t working for me.

Configure OPNsense Bridge on a Sophos SG125 V2

Mon, 22 Dec 2025 23:10:03 +0200

I recently purchased two Sophos SG 125 V2s with OPNsense. These have several physical (Layer 3) interfaces, which I would like to combine into a bridge. This allows multiple interfaces to be treated like a switch (Layer 2) and assigned to the same network without having to configure each interface individually.

Sophos has a DMZ, a LAN, an HA, a WAN, and several normal Ethernet ports. I would like to set up the Ethernet ports together as a bridge.