[arch-general] script idea - update single arch box -> updates all on local net

[David C. Rankin]

Guys,

	I've played with an idea to save time with updates and duplicate (old version)
removal from /var/cache/pacman/pkg for all arch boxes on a local network. I
thought I would pass along the idea and the scripts as they exist now.

Requirements:

 - public key/private key ssh access for user between boxes on the lan (id_dsa)
 - sudo rights for user on each box

Config:

 - all script calls to additional scripts are to symlinks in /usr/local/bin

Operation:

  pmduprsync.sh - is the outside script that runs pacman -Syu --noconfirm on a
box on the lan (you can nix the --noconfirm if you want to review).

  --  it then calls fduparch.sh (which just sets the directories to remove old
      version of the packages from/to (I've posted a full description before).
      Which then calls:

    --  fduppkg (the actual script that scans /var/cache/pacman/pkg and moves
        old versions of packages to another directory of your chosing.
        (currently /home/backup/pkg-old for me)

  --  fduparch.sh runs a second time for me to remove old versions from
      /home/backup/pkg-old to /home/backup/pkg-older (original I know)

  pmduprsync.sh grabs a md5sum of the /var/cache/pacman/pkg dir on the remote
  hosts of the same arch and then rsyncs /var/cache/pacman/pkg dir to remote
  host and grabs another md5sum. If the sums differ, then pacman -Syu
  --noconfirm is called on the remote host following by fduparch.sh to tidy up
  the /var/cache/pacman/pkg dir there.

	For me the benefit is I keep a current package set for all boxes in the package
dir of each host (not an issue in the days of 1T drives). Further, bandwidth
reduction. Packages are only downloaded once and rsynced between boxes.

	Now granted the --noconfirm isn't optimal, and I always check first before
pulling the trigger, but the automation of checking what an update will include
on one host (generally the host with the widest package selection) and then
having the updates daisy-chain to all other arch boxes on the lan while tidying
up /var/cache/pacman/pkg on each box is a big plus.

	Currently you will see that I've just hard coded which hosts are i686 and
x86_64 in pmduprsync.sh (easy at home - only 4 boxes 2 of each arch), but there
is no reason why either an i686/x86_64 host list file couldn't be automagically
built with some type of subnet host query followed up with ssh 'uname -r' calls.

	Anyway here are the scripts in case it sparks an idea with someone else.
Regardless of whether you want the auto update part, the scripts that move old
versions of packages from /var/cache/pacman/pkg have served me well.

http://www.3111skyline.com/dl/Archlinux/scripts/pmduprsync.sh
http://www.3111skyline.com/dl/Archlinux/scripts/fduparch.sh
http://www.3111skyline.com/dl/Archlinux/scripts/fduppkg

	Once I refine the logic in the update script a bit more and the collection of
hosts with the same arch on the lan, I'll follow up. All the scripts are my
original work and are gpl, so use, reuse, tear apart at will.


-- 
David C. Rankin, J.D.,P.E.
Rankin Law Firm, PLLC
510 Ochiltree Street
Nacogdoches, Texas 75961
Telephone: (936) 715-9333
Facsimile: (936) 715-9339
www.rankinlawfirm.com