Day: 31 October 2021

Chips Water Innovation

This is a bit old news. But I found interesting the connection between chips manufacturing and water. And this is brilliant.

I want the world to be dependent on me, but I don’t want to be dependent on anybody else.” I don’t think it’s going to happen.

As well, I left for granted that all innovation for COVID vacciones was just miraculous, but it seems it was something feeding from successful innovation strategies.

So moving forwards, and I guess that should be valid to any country, you need to invest in innovation, R&D. It is expensive but it is worth long run. See TSMC.

OTP attacks

Reading a bit of old news about One-Time-Passwords attacks (link1 and link2) I realized that there is no much awareness in companies about this danger. Most people assume that having 2FA means the perfect security system. But it seems it is not and we have to be still even more vigilant. Trust is earned not deserved. So we need a bit of common sense practices spread around this topci. I liked the explanation about the link used for attacking coinbase and how slick was the method of using a subdomain that in a mobile screen only shows the small part and tricks you.

Prince of Persia

A couple of months ago I was reading about how the game DOOM was ported to a product from a CDN company. I remember I played a bit and brought back good memories when I was playing DOOM2. Even the code was published in github. Somehow I clicked to the book about DOOM and found about a book about Prince of Persia. I bought both at the end.

The book about POP was quick to read. It is “just” the journals of the author across some years. It is interesting how much has changed the industry since late 80s. He though the gaming industry wasn’t going to last long. 30 years later we have even “e-sports”! I didnt know he wrote the whole game. I assumed this kind of projects were managed by big teams. But those times, things were simpler and a good hacker could do those things. And he was super young! And before that he wrote the game “Karateka” that I dont remember. Anyway, Prince of Persia was one of my favourite games! And now you can still play online. I think I played a bit the second part but that was it. I always kept loyal to the first part. As a journal you can read the struggles of the person. He wanted to make movies but then the gaming thing was always calling him. I think it is quite interesting what he did as he was travelling, writing scripts and then video games in the late 80s and 90s.

Use ZFS

As part of my reinstallation, I had to create a ZFS partition that I used to use for personal storage. Debian Installation process doesnt provide this option, so I have to do it manually. To be honest, it is good to remember/refresh these “basic” things, you never know when you are going to need them (urgently very likely).

As the installation process gave most of the space to the “home” partition, that’s the one I need to take space for creating my ZFS partition. I chose LVM during installation so I dont really have to deal with physical partition, it is mainly logical volumes aka “lv”.

So I rebooted in single-mode as I wanted to be sure that I didnt damage anything and I had to umount the “home” lv. So as root:

Check mounted partitions
# df -hT

Checks LV summary
# lvs

Umount /home
# umount /home/

Check "home" is not munted
# df -hT

Check VolgumeGroup summary
# vgs

Perform filesystem check before making any change
# e2fsck -fy /dev/mapper/athens--vg-home

Resize filesystem to 22G
# resize2fs /dev/mapper/athens--vg-home 22G

Check LV hasnt changed
# lvs

Reduce LV for home to 22G
# lvreduce -L 22G /dev/mapper/athens--vg-home

Check LV home is reduced
# lvs
  LV      VG        Attr       LSize   Pool Origin Data%  Meta%  Move Log Cpy%Sync Convert
  home    athens-vg -wi-ao----  22.00g                                                    
  root    athens-vg -wi-ao---- <27.94g                                                    
  swap_1  athens-vg -wi-ao---- 976.00m                                                    
# 

Check you have free space in the VG
# vgs
  VG        #PV #LV #SN Attr   VSize   VFree   
  athens-vg   1   3   0 wz--n- 237.48g <186.59g
# 

Reboot to be sure everything is fine
# reboot

Check all partitions are mounted and "home" is just 22G
$ df -hT
Filesystem                  Type      Size  Used Avail Use% Mounted on
udev                        devtmpfs  3.9G     0  3.9G   0% /dev
tmpfs                       tmpfs     786M  1.6M  785M   1% /run
/dev/mapper/athens--vg-root ext4       28G  6.7G   20G  26% /
tmpfs                       tmpfs     3.9G   87M  3.8G   3% /dev/shm
tmpfs                       tmpfs     5.0M  8.0K  5.0M   1% /run/lock
/dev/sda2                   ext2      456M   72M  360M  17% /boot
/dev/mapper/athens--vg-home ext4       21G  3.0G   17G  16% /home
/dev/sda1                   vfat      496M   64M  433M  13% /boot/efi
tmpfs                       tmpfs     786M   40K  786M   1% /run/user/1000
$

Create new LV "storage" using the spare space in the VG
# lvcreate -L 186G -n storage athens-vg
  Logical volume "storage" created.
# 

Check VG space has reduced
# vgs
  VG        #PV #LV #SN Attr   VSize   VFree  
  athens-vg   1   4   0 wz--n- 237.48g 604.00m
#

Check we have a new LV storage of 186G
# lvs
  LV      VG        Attr       LSize   Pool Origin Data%  Meta%  Move Log Cpy%Sync Convert
  home    athens-vg -wi-ao----  22.00g                                                    
  root    athens-vg -wi-ao---- <27.94g                                                    
  storage athens-vg -wi-a----- 186.00g                                                    
  swap_1  athens-vg -wi-ao---- 976.00m                                                    
#

Create our Zpool storage using the LV storage.
# zpool create storage /dev/mapper/athens--vg-storage 

Check Zpool status
# zpool status
  pool: storage
 state: ONLINE
config:

	NAME                  STATE     READ WRITE CKSUM
	storage               ONLINE       0     0     0
	  athens--vg-storage  ONLINE       0     0     0

errors: No known data errors
#

Check mount point for ZFS pool
# zfs get mountpoint storage
NAME     PROPERTY    VALUE       SOURCE
storage  mountpoint  /storage    default
# 

Change Zpool storage mount point to a point in my home dir
# zfs set mountpoint=/home/tomas/storage storage

Check ZFS list
# zfs list
NAME      USED  AVAIL     REFER  MOUNTPOINT
storage   165K   179G       24K  /home/yo/storage
# 

Check all partitions
$ df -hT
Filesystem                  Type      Size  Used Avail Use% Mounted on
udev                        devtmpfs  3.9G     0  3.9G   0% /dev
tmpfs                       tmpfs     786M  1.6M  785M   1% /run
/dev/mapper/athens--vg-root ext4       28G  6.7G   20G  26% /
tmpfs                       tmpfs     3.9G   87M  3.8G   3% /dev/shm
tmpfs                       tmpfs     5.0M  8.0K  5.0M   1% /run/lock
/dev/sda2                   ext2      456M   72M  360M  17% /boot
/dev/mapper/athens--vg-home ext4       21G  3.0G   17G  16% /home
/dev/sda1                   vfat      496M   64M  433M  13% /boot/efi
tmpfs                       tmpfs     786M   40K  786M   1% /run/user/1000
storage                     zfs       180G  128K  180G   1% /home/y/storage
$

I have used these links to refresh myself:

  • lvs resize: https://www.rootusers.com/lvm-resize-how-to-decrease-an-lvm-partition/
  • create lv: https://www.thegeekstuff.com/2010/08/how-to-create-lvm/
  • create zfs pool: https://ubuntu.com/tutorials/setup-zfs-storage-pool#3-creating-a-zfs-pool
  • change zfs mount point: https://docs.oracle.com/cd/E19253-01/819-5461/gaztn/index.html

To be honest, I thought I was going to struggle much more but it has been quick.

Step by step getting back to my normal environment (and trying to improve it). I said it before, I should be able to reinstall my laptop easily, like a production server….