Arch Linux

trurl

Member

Registered: 2011-05-18

Posts: 3

migration from Gentoo

Here is a newbie question...
I do have a Gentoo installation with 5 disks
each with 2+ partitions running ReiserFS, XFS, ext2

I am very seriously contemplating migrating to Arch
but I would like to reuse my disks, partitions, filesystems...

I certainly don't want to reformat my disks.

Is it possible to retain my filesystems? (except any
system stuff, of course)

ewaller

Administrator

From: Pasadena, CA

Registered: 2009-07-13

Posts: 19,785

Re: migration from Gentoo

First, welcome from a fellow Gentoo refugee.  I do like them both, but it so much easier to keep Arch running.

The general answer to your question is: yes.

Could you provide a bit more information on your partitioning?  For a while, I maintained two root partitions, one with Gentoo, the other with Arch.  Other than than, home and swap and boot were used for both.

---

Nothing is too wonderful to be true, if it be consistent with the laws of nature -- Michael Faraday
Sometimes it is the people no one can imagine anything of who do the things no one can imagine. -- Alan Turing
---
How to Ask Questions the Smart Way

trurl

Member

Registered: 2011-05-18

Posts: 3

Re: migration from Gentoo

Wow! That was a quick answer :-)

I've used Gentoo for, hmmm..., close to 10 years! Time flies...
A performance freak, I had been attracted to Gentoo by the notion that you can custom compile
all packages for your exact system. I also like the rolling release concept.

But on more than one occasion I have been bitten by "emerge -u world"
Long story short: things can go bad and instead of working on
my main topic (Android tablet eBook reader for O'Reilly books, called eCarrel)
I spend time googling around, browsing forums, "problem solving & researching"
how to get back to a working system :-(
All these 'revdep-rebuilds', 'python-updaters' -- I guess I've had enough!

Just look at the Gentoo Forums: chock-full of threads/posts about getting out of trouble.

I have 3 fast SCSI disks using ReiserFS for everything except /boot (ext2)
I have separate partitions for / (root) /home /opt /tmp /var (all Reiser).
And then 2 larger SATA disks for media (movies, photo scans, music)
with XFS and possibly also Reiser.

Filesystem    Type    Size  Used Avail Use% Mounted on
/dev/sda3 reiserfs     31G   28G  2.9G  91% /
udev         tmpfs     10M  324K  9.7M   4% /dev
/dev/sdb1 reiserfs    3.9G  1.2G  2.7G  31% /var
/dev/sdb2 reiserfs    2.0G   80M  1.9G   5% /tmp
/dev/sdb3 reiserfs     29G   17G   12G  59% /opt
/dev/sdc1 reiserfs     18G   15G  2.4G  87% /home
/dev/sde1      xfs    466G  300G  167G  65% /mnt/data1
shm          tmpfs    1.8G  528K  1.8G   1% /dev/shm
/dev/sdd2      xfs    233G  113G  121G  49% /tmp/disk

I will be happy with one root.
But I really don't want to loose my data.

Thank you for your help!

lucke

Member

From: Poland

Registered: 2004-11-30

Posts: 4,018

Re: migration from Gentoo

During installation you can just provide mountpoints, without running mkfs. All your filesystems are supported by vanilla (hence also arch's) kernel and grub.

ewaller

Administrator

From: Pasadena, CA

Registered: 2009-07-13

Posts: 19,785

Re: migration from Gentoo

It looks to me like you could use it just about as is.  I would just reformat sda3 (After you make sure there is nothing there you want to keep;) )
Other than that, tell the installer about your structure and make sure you tell it to use the existing file systems for everything besides sda3.  Be careful and read the installer messages as to what is going to do carefully.

Other than that, you should have a swap partition someplace.  You can use that as is as well.

Eventually you may want to clean out /var of all the Gentoo package caches.  Arch will be putting its own in /var/lib/pacman.

If you want to compile your own, you will want to install abs.  It will install all of the PKGBUILDs (the Arch equivalent of ebuilds) in /var/abs.  You can copy individual entries to a directory of your choice and build custom stuff to your heart's content.

---

Nothing is too wonderful to be true, if it be consistent with the laws of nature -- Michael Faraday
Sometimes it is the people no one can imagine anything of who do the things no one can imagine. -- Alan Turing
---
How to Ask Questions the Smart Way

trurl

Member

Registered: 2011-05-18

Posts: 3

Re: migration from Gentoo

My fstab is quoted below. For this system I built from (newegg) parts
I had used Q6600 Quad and 4 GB of RAM.
Following the old school of thought I allocated 4GB swap on sda2
but I think I've been wasting disk: I  have never seen even 1 GB
of swap used, ever. Perhaps I can repartition that disk...

/dev/sda1               /boot           ext2            noauto,noatime  1 2
/dev/sda3               /               reiserfs        noatime         0 1
/dev/sda2               none            swap            sw              0 0

/dev/sdb1               /var            reiserfs        noatime         0 1
/dev/sdb2               /tmp            reiserfs        noatime         0 1
/dev/sdb3               /opt            reiserfs        noatime         0 1

/dev/sdc1               /home           reiserfs        noatime         0 1

/dev/sde1               /mnt/data1      xfs             noatime         0 1

my0pic

Member

From: Melbourne, Australia

Registered: 2008-05-23

Posts: 206

Re: migration from Gentoo

If you're the adventurous type here's an alternative way to migratate from Gentoo.
Not recommended of course

As for the amount of swap, with 4G of ram you have enough to not need a swap partition. Of course that depends on what type of work you do on your machine. But if as you say in normal use you haven't seen any swap usage, then you should be ok. Note also that if needed, you can create a swap file to use instead of a partition.

Last edited by my0pic (2011-05-19 01:43:04)