Stop the POP! from Debian/Ubuntu sound devices

By default the Linux kernel will put unused devices into a power saving mode to promote battery life on portable devices. This has the unfortunate effect of causing an audible pop when the kernel wakes the sound driver to emit sound after which it will put the driver back into power saving mode after a time without activity for the driver. Causing another pop - naturally 😒

To check if your driver module is configured to do this cat the following file

cat /sys/module/snd_hda_intel/parameters/power_save

If a 1 is returned then yes, your sound device is using the power save feature.
You can temporarily turn it off with the following:

echo "0" | sudo tee /sys/module/snd_hda_intel/parameters/power_save 

Test you notification sounds, they sound now be clear and pop free.

This option can be permenantly disabled, by creating an option file in /etc/modprobe.d 

This can be done with the following:

echo "options snd_hda_intel power_save=0" | sudo tee -a /etc/modprobe.d/audio_disable_powersave.conf

Enjoy your pop free sound !

Installing Proxmox with Linux raid

I this article I will explain how to setup Debian using LVM & RAID 1 (mirror). Then install Proxmox on top and setup the necessary thinpool.
 
NOTE: This is *NOT* a supported installation of Proxmox and as such should not be used in a production environment. It is provided as an educational material only.
 
First install Debian as normal, when prompted create a raid mirror and LVM volumes for the root filesystem and the swap.

A standard install + ssh server will easily fit into an 8G volume leaving about 4G free.

Once installed check for updates (apt update && apt-dist-upgrade). Check the status of the raid array using mdadm --detail /dev/md0
 
Ensure that mdadm reports that the array is in a clean state (I.e. healthy). 

It should look something like this:

/dev/md0:

     Version : 1.2

     Creation Time : Mon Nov  1 14:28:10 2021

     Raid Level : raid1

     Array Size : 33534976 (31.98 GiB 34.34 GB)

     Used Dev Size : 33534976 (31.98 GiB 34.34 GB)

     Raid Devices : 2

     Total Devices : 2

     Persistence : Superblock is persistent

     Update Time : Wed Nov 17 13:50:53 2021

     State : clean

     Active Devices : 2

    Working Devices : 2

    Failed Devices : 0

    Spare Devices : 0

Consistency Policy : resync

              Name : TESTPVE4:0  (local to host TESTPVE4)

              UUID : da8e61c0:9bb61b6c:aea14209:b4ce52a8

            Events : 1538

    Number   Major   Minor   RaidDevice State

       3       8        1        0      active sync   /dev/sda1

       2       8       17        1      active sync   /dev/sdb1

running pvs to scan your physical volumes should be similar to this:

 PV         VG  Fmt  Attr PSize  PFree  
 /dev/md0   pve lvm2 a--  31.98g 928.00m

Your volume groups should be similar to this:

  VG  #PV #LV #SN Attr   VSize  VFree  
  pve   1   4   0 wz--n- 31.98g 928.00m

And lastly your logical volume scan should look like this:

  LV            VG  Attr       LSize  Pool Origin Data%  Meta%  Move Log Cpy%Sync Convert
  root          pve -wi-ao----  9.31g                                                    
  swap          pve -wi-ao----  3.72g                                                    

Now that your system is running with LVM running on raid , dont forget to install the grub bootloader on the second disk of the mirrored array (/dev/sdb). Otherwise you will not be able to boot if /dev/sda fails.

grub-install /dev/sdb

This can be tested by shutting down the system and unplugging /dev/sda and booting up again. The system should (after complaining that a disk is missing) boot up normally. 

NOTE: If you perform the test above wait for the array to rebuild once both drives are connected, use mdm --detail /dev/md0 to monitor the array and continue once the array is marked as clean.

If all looks well you can create the LVM thinpool for use by proxmox by running lvcreate

lvcreate -L 18G --thinpool data pve

In this example a thinpool of 18G is created named data within the pve volume group. You will need to adjust the command as appropriate for your needs.

If all goes well running lvs should show all you previous logical volumes as well as your new thin pool !

  LV            VG  Attr       LSize  Pool Origin Data%  Meta%  Move Log Cpy%Sync Convert

  data          pve twi-aotz-- 18.00g             8.02   13.93                           

  root          pve -wi-ao----  9.31g                                                    

  swap          pve -wi-ao----  3.72g                                                   

Next up, install Proxmox onto your Debian installation by following the instructions contained in the Proxmox documentation.

Wuauclt Usage

 WUAUCLT.EXE 

A command line utility to control the Windows Update Automatic Update CLient

This utility is provided for all Windows operating systems prior to the release of Windows 10/Server 2016. It provides the ability to invoke an update scan or report statistics to a WSUS (Windows Software Update Service).

For reasons known only to Micrososoft, they did not include a help option (/?) as one of  the parameters for this utility. I've only listed options that have a known effect to the client.

• /DetectNow - To run an immediate poll of the WSUS server for updates
• /resetAuthorization - To reset the authorization on the server and the client. In fact, it is a new registration on the WSUS server. Useful when the client registraation is corrupt, deleting it on the server and the command wuauclt /detectnow /resetAuthorization re-registered on the server with simultaneous request for list of updates
• /reportnow To reset the statistics on the server the Other parameters are not so obvious and, most importantly, their application is not clear and usually causes no change
• /ShowSettingsDialog - Displays the dialog to set the schedule for the installation of the updates
• /ResetEulas - to reset the EULA for updates
• /ShowWU - go to website of MS updates
• /ShowWindowsUpdate - go to website of MS updates
• /UpdateNow - Immediately starts the update process, clicking the same button in the notification window when updates are available.
• /ShowWUAutoScan - unknown
• /ShowFeaturedUpdates - unknown
• /ShowOptions - unknown
• /ShowFeaturedOptInDialog - unknown
• /DemoUI - Show icon in tray - settings dialog schedule the installation of updates or setup, depending on the status.