Categories: "*nix"

VMware - Accessing the BIOS when the POST screen clears too quickly

April 5th, 2022

Edit the .vmx file for the VM in question and add the following line:

bios.bootDelay = "5000"

This will increase the POST screen delay to 5 seconds

 

grub2 - remember last selected item

March 21st, 2022

For nearly all cases, I want the bootloader on a multi-boot machine to boot into the last selected option.  I've had grub2 on a number of distros now and I always need to jump through hoops to get this to work properly.  It looks like I need to do a couple things:

1. Edit the /etc/default/grub file and ensure the following two lines exist:

GRUB_DEFAULT=saved
GRUB_SAVEDEFAULT=true

2. Update grub.  For debian/ubuntu, the command is:

update-grub

for Arch/Rocky the command is:

grub2-mkconfig –o /boot/grub2/grub.cfg

Now for the hitch - on an EFI system (at least Arch and Rocky), you ALSO need to run this command (substituting the appropriate distribution name):

grub2-mkconfig -o /boot/efi/EFI/centos/grub.cfg

Remove SSH Entry from Known Hosts

March 17th, 2022

Remove 10th line from known hosts:

sed -i '10d' ~/.ssh/known_hosts

Remove all keys belonging to my.host.com from known hosts:

ssh-keygen -R my.host.com

Unraid Web GUI Failed Password Lockout

January 7th, 2022

In version 6.9.2, Unraid added a lockout for 3 login attempts (per IP address).  I often fail this and am locked out from the Web UI while I impatiently wait for the timeout to expire.  Here is a quote from the release notes:

For webGUI login you now get 3 login attempts per IP address before a 15-minute cool off is enforced. Further, the timestamp of the last three failed login attempts per IP address are stored in files located in /var/log/pwfail/<ip-address>. Note this only applies to webGUI login, not ssh or telnet.

So, it appears that if you remove the file corresponding to your IP address on the Unraid server in the /var/log/pwfail directory, you don't have to wait for the timeout.  

Solar Powered WiFi Weather Station

January 3rd, 2022

I've been looking for a reliable way to get outdoor temperature into Home Assistant for automation purposes.  I've been using openweather which gets the weather at San Martin airport, but the reported temperatures versus what the temperature actually is here can sometimes be off by more than 5 degrees.  This is a solution that I can mount outside and doesn't require any electricity to run.  I did end up moving to a remote mounted solar panel which was twice the size (and output wattage) as the original.  This allowed me to put the sensor in the gazebo in an always shaded, yet open to air location which is unlikely to be impacted by sun impacting the actual temperature readings.

Here are some related links:

Solar Powered WiFi Weather Station V2.0
Solar Powered WiFi Weather Station V2.0 (PCBWay)
Solar E-ink Weather Station
Solar Powered WiFi Weather Station V2.0 Enclosure (Thingiverse)
Stevenson Screen for Solar Weather Station V2 (Thingiverse)
Solar Powered WiFi Weather Station V2 (Thingiverse)
Solar panel holder (Thingiverse)