Sometimes Linux will mistakenly detect a floppy device and create a reference to it because your system does not actually have a floppy drive and you will see errors on the login screen that look similar to blk_update_request: I/O error, dev fd0, sector 0. I find this frequently happens on a VMWare VM. This doesn’t…
Generate Certificate Signing Request (CSR) in Linux
Replace domain with your domain. domain.csr is what is used by your certificate authority togenerate your certificate. domain.key will be used by your web server in conjunction with yourcertificate.
Fix software updates in Cockpit in Ubuntu 20.04
Software updates on the Ubuntu system will fail because Cockpit on Ubuntu doesn’t detect a networkconnection. To fix this, you must use NetworkManager instead of the default networkd. You need to be root or sudo root for all these commands. Edit your netplan file in /etc/netplanand add the following two lines under network:. Remember that…
Convert Aruba AP-325 from Campus mode to Instant mode
There are two versions of the Aruba AP-325. One version is the Campus AP that has 256MB of RAM. The other version is the Instant-AP with 512MB of RAM. Campus APs that are converted to Instant APs are limited to ArubaOS 6 and cannot be upgraded further even if Aruba Central or the AP themselves…
Enable Melanox Connect X support in OPNsense
Support for Mellanox Connect-X NICs aren’t enabled on OPNsense by default. The following line has to be added to /boot/loader.conf.local. However this did not work for me and I had to add this from the web interface, System → Settings→ Tunables.
Install syslinux on Windows Server 2019 WDS
Once Windows Deployment Services is installed and running, locate the folder where WDS is installed.My install is in D:\RemoteInstall. Rename pxeboot.n12 in D:\RemoteInstall\Boot\x64 to pxeboot.0. Rename abortpxe.com in D:\RemoteInstall\Boot\x86 to abortpxe.0. Download syslinux. I used version 5.04. Your mileage may vary with other versions. From the syslinux archive, extract core\pxelinux.0, com32\menu\vesamenu.c32, com32\modules\chain.c32, memdisk\memdisk to D:\RemoteInstall\Boot\x86…
PXE Config examples
I’ve set up a local http web server. You can use another web server mirror if you want.
Install telnet, ftp on MacOS
telnet and ftp have been removed from Mac. While people shouldn’t be using insecure versions ofthese protocols, I use telnet often to diagnose connections issues. The solution to this is to installinetutils. You can install inetutils using Homebrew or MacPorts, but I prefer compiling from source. It is morestraight-forward and does not require installing additional…
Set up unattended-upgrades on Ubuntu 20.04
Package upgrades can be set up to install updates on Ubuntu without user intervention. Install unattended-upgrades Install mailx & Postfix If this does not install Postfix, install it now. This will install also install Postfix. mailx is what unattended upgrades uses to send external mail. Configure unattended-upgrades. Edit /etc/apt/apt.conf.d/50unattended-upgrades. This file is mostly self explanatory….
Install GNS3 on UNRAID on your local
network
GNS3 allows network engineers to model networks. Unlike network simulators, GNS3 uses real deviceimages. The devices run on a hypervisor. Unraid is an easy to use NAS operating system based onSlackware that supports docker images and virtual machines. Create a VM in Unraid We will be using Ubuntu 20.04 as the base of GNS3. Install…