Linux Multiboot - /etc/fstab

This is a four-parts article. There are few sections here.

Supplementary Article for BSD.

Preface

Goal: Thorough /etc/fstab/ example

Table of Content

Preface: Table of Content
Overview
1: Using Device Path
2: Using UUID
3: Common Mount Point
4: Custom Mount Point
What is Next?

Overview

There are three parts of mount point on fstab, that we are going to talk about.

Initial: clean install: root and swap
Common: shared partition, and windows data partititon
Custom: access to other OS
- OpenSUSE: access to: Fedora, Debian, KaOSx.
- Fedora: access to: openSUSE, Debian, KaOSx.
- Debian: access to: openSUSE, Fedora, KaOSx.
- KaOSx: access to: openSUSE, Fedora, Debian.

Device Name and UUID

There are two approach of setting mount point

Using device path: e.g /dev/sda9
Using UUID: e.g c114d95e-bc0a-4b41-a2db-abd21aa9850f

List Block Device

We are going to use lsblk, to have a listing of our beloved block device .

% lsblk   
NAME    MAJ:MIN RM   SIZE RO TYPE MOUNTPOINT
sda       8:0    0 465.8G  0 disk 
├─sda1    8:1    0 131.9G  0 part /media/System
├─sda2    8:2    0     1K  0 part 
├─sda5    8:5    0  57.7G  0 part /media/Works
├─sda6    8:6    0  66.4G  0 part /media/Docs
├─sda7    8:7    0   999M  0 part /media/Boot
├─sda8    8:8    0   9.9G  0 part /media/Fun
├─sda9    8:9    0  49.1G  0 part /media/openSUSE
├─sda10   8:10   0  49.1G  0 part /media/KaOSx
├─sda11   8:11   0  49.1G  0 part /
├─sda12   8:12   0  49.1G  0 part /media/Debian
└─sda13   8:13   0   2.5G  0 part [SWAP]

Multiboot: custom: lsblk

Dotfiles Document

Config is available at:

github.com/epsi-rns/dotfiles/…/multiboot

1: Using Device Path

Since openSUSE with BTRFS is complex, I’m going to start with Fedora.

Before we use UUID, I start with device name. It is easier to read /dev/sda9 than read c114d95e-bc0a-4b41-a2db-abd21aa9850f.

Manual Page

This is where to get help.

$ man fstab

Multiboot: man fstab

Initial

Depend on your installation, your minimum fstab contain only this two entry.

# Fedora

/dev/sda11   /                 ext4      defaults                                1       1
/dev/sda13   none              swap      swap                                    0       0

Multiboot: initial: lsblk -o

Common

Add shared Partition. And this Windows is common to all linux.

### Common

/dev/sda1    /media/System     ntfs-3g   defaults,noauto,locale=en_US.UTF-8      0       0
/dev/sda6    /media/Docs       ntfs-3g   defaults,locale=en_US.UTF-8             0       0
/dev/sda5    /media/Works      ext4      defaults,users,exec                     0       2

Multiboot: common: lsblk -o

Custom Access

How about the rest.

### Other Distribution

/dev/sda10   /media/KaOSx      xfs       defaults,noauto,users                   0       0
/dev/sda12   /media/Debian     ext4      defaults,noauto,users                   0       0

### OpenSUSE

/dev/sda9    /media/openSUSE   btrfs     defaults,noauto,users                   0       0
/dev/sda7    /media/Boot       ext4      defaults,noauto,user,errors=remount-ro  0       0
/dev/sda8    /media/Fun        xfs       defaults,noauto,users                   0       0

Multiboot: custom: lsblk -o

And the result of lsblk -o is:

% lsblk -o NAME,FSTYPE,LABEL,MOUNTPOINT
NAME    FSTYPE LABEL  MOUNTPOINT
sda                   
├─sda1  ntfs   System /media/System
├─sda2                
├─sda5  ext4   Works  /media/Works
├─sda6  ntfs   Docs   /media/Docs
├─sda7  ext4   boot   /media/Boot
├─sda8  xfs    Fun    /media/Fun
├─sda9  btrfs         /media/openSUSE
├─sda10 xfs    KaOSx  /media/KaOSx
├─sda11 ext4   Fedora /
├─sda12 ext4   Debian /media/Debian
└─sda13 swap          [SWAP]

Complete

And finally this is all.

# Fedora
# /etc/fstab

/dev/sda11   /                 ext4      defaults                                1       1
/dev/sda13   none              swap      swap                                    0       0

### Common

/dev/sda1    /media/System     ntfs-3g   defaults,noauto,locale=en_US.UTF-8      0       0
/dev/sda6    /media/Docs       ntfs-3g   defaults,locale=en_US.UTF-8             0       0
/dev/sda5    /media/Works      ext4      defaults,users,exec                     0       2

### Other Distribution

/dev/sda10   /media/KaOSx      xfs       defaults,noauto,users                   0       0
/dev/sda12   /media/Debian     ext4      defaults,noauto,users                   0       0

### OpenSUSE

/dev/sda9    /media/openSUSE   btrfs     defaults,noauto,users                   0       0
/dev/sda7    /media/Boot       ext4      defaults,noauto,user,errors=remount-ro  0       0
/dev/sda8    /media/Fun        xfs       defaults,noauto,users                   0       0

Additional entry

However, there are entry on the fourth field, like this one:

defaults,noauto,users

You can read what it mean in mount manual page.

$ man 8 mount

Multiboot: man mount

Shared partition

I have my shared partition at /media/Works

Except for working partition, I want to make my script executable.

defaults,users,exec

My working partition is going to be automatically mounted, at boot time. Because I put my samba (network neighbourhood) directory over there.

2: Using UUID

Now we are going to convert each device name such as /dev/sda9, to UUID such as c114d95e-bc0a-4b41-a2db-abd21aa9850f. First, consider what the map in your PC.

% tree /dev/disk/by-uuid
/dev/disk/by-uuid
├── 0095473d-ae63-4722-8350-f5716e5df333 -> ../../sda8
├── 01CF01333AD2FF20 -> ../../sda6
├── 23342d48-c3be-402c-b049-b3e9ddeafbc0 -> ../../sda7
├── 4190d7a9-fb03-4d19-864f-7d04f89c3be0 -> ../../sda12
├── 442456A824569CAC -> ../../sda1
├── 50f93bc6-711d-4f70-84cf-09748e653543 -> ../../sda10
├── 954a9b1e-c8c0-4f38-8877-fa891c79c9ae -> ../../sda5
├── 9c76fb33-fa7a-46af-b2bb-f82d385b81b6 -> ../../sda11
├── b623e30b-c7a5-4f99-a250-45372da4c5b4 -> ../../sda13
└── c114d95e-bc0a-4b41-a2db-abd21aa9850f -> ../../sda9

0 directories, 10 files

Partition: Disk by UUID

Fedora

Still, I’m going to start with Fedora. Clean Install without additional mount point.

Depend on your installation, your minimum fstab contain only this two entries.

UUID=9c76fb33-fa7a-46af-b2bb-f82d385b81b6   /       ext4   defaults                         1       1
UUID=b623e30b-c7a5-4f99-a250-45372da4c5b4   none    swap    swap                            0       0

In a complete fashion, this would be:

# Fedora
#
# /etc/fstab
# Created by anaconda on Fri Jul 21 22:03:59 2017
#
# Accessible filesystems, by reference, are maintained under '/dev/disk'
# See man pages fstab(5), findfs(8), mount(8) and/or blkid(8) for more info
#

# / was on /dev/sda11 during installation
UUID=9c76fb33-fa7a-46af-b2bb-f82d385b81b6   /       ext4   defaults                         1       1

# swap was on /dev/sda13 during installation
UUID=b623e30b-c7a5-4f99-a250-45372da4c5b4   none    swap    swap                            0       0

mtab

Consider cross check the result with /etc/mtab. Note that normally swap would not be shown.

% cat /etc/mtab | grep sda | column -t
/dev/sda11  /  ext4  rw,relatime,data=ordered  0  0

Multiboot: initial mtab

Debian

In a same way, consider have a look at ext4 in Debian.

# / was on /dev/sda12 during installation
UUID=4190d7a9-fb03-4d19-864f-7d04f89c3be0   /       ext4     errors=remount-ro          0       1

# swap was on /dev/sda13 during installation
UUID=b623e30b-c7a5-4f99-a250-45372da4c5b4   none    swap    sw                          0       0

/dev/sr0          /media/cdrom0     udf,iso9660 user,noauto                             0       0

KaOSx

And, also have a look at XFS in KaOSx.

# / was on /dev/sda10 during installation
UUID=50f93bc6-711d-4f70-84cf-09748e653543 /         xfs     defaults,noatime            0       1

# swap was on /dev/sda13 during installation
UUID=b623e30b-c7a5-4f99-a250-45372da4c5b4 swap      swap    defaults,noatime            0       0

It is pretty much the same with XFS.

openSUSE

But very different with BTRFS in openSUSE.

# / was on /dev/sda9 during installation

UUID=23342d48-c3be-402c-b049-b3e9ddeafbc0 /boot                     ext4       errors=remount-ro     0 1
UUID=c114d95e-bc0a-4b41-a2db-abd21aa9850f /                         btrfs      defaults              0 0
UUID=0095473d-ae63-4722-8350-f5716e5df333 /home                     xfs        defaults              1 2
UUID=b623e30b-c7a5-4f99-a250-45372da4c5b4 swap                      swap       defaults              0 0
UUID=c114d95e-bc0a-4b41-a2db-abd21aa9850f /boot/grub2/i386-pc       btrfs      subvol=@/boot/grub2/i386-pc 0 0
UUID=c114d95e-bc0a-4b41-a2db-abd21aa9850f /boot/grub2/x86_64-efi    btrfs      subvol=@/boot/grub2/x86_64-efi 0 0
UUID=c114d95e-bc0a-4b41-a2db-abd21aa9850f /opt                      btrfs      subvol=@/opt          0 0
UUID=c114d95e-bc0a-4b41-a2db-abd21aa9850f /srv                      btrfs      subvol=@/srv          0 0
UUID=c114d95e-bc0a-4b41-a2db-abd21aa9850f /tmp                      btrfs      subvol=@/tmp          0 0
UUID=c114d95e-bc0a-4b41-a2db-abd21aa9850f /usr/local                btrfs      subvol=@/usr/local    0 0
UUID=c114d95e-bc0a-4b41-a2db-abd21aa9850f /var/cache                btrfs      subvol=@/var/cache    0 0
UUID=c114d95e-bc0a-4b41-a2db-abd21aa9850f /var/crash                btrfs      subvol=@/var/crash    0 0
UUID=c114d95e-bc0a-4b41-a2db-abd21aa9850f /var/lib/libvirt/images   btrfs      subvol=@/var/lib/libvirt/images 0 0
UUID=c114d95e-bc0a-4b41-a2db-abd21aa9850f /var/lib/machines         btrfs      subvol=@/var/lib/machines 0 0
UUID=c114d95e-bc0a-4b41-a2db-abd21aa9850f /var/lib/mailman          btrfs      subvol=@/var/lib/mailman 0 0
UUID=c114d95e-bc0a-4b41-a2db-abd21aa9850f /var/lib/mariadb          btrfs      subvol=@/var/lib/mariadb 0 0
UUID=c114d95e-bc0a-4b41-a2db-abd21aa9850f /var/lib/mysql            btrfs      subvol=@/var/lib/mysql 0 0
UUID=c114d95e-bc0a-4b41-a2db-abd21aa9850f /var/lib/named            btrfs      subvol=@/var/lib/named 0 0
UUID=c114d95e-bc0a-4b41-a2db-abd21aa9850f /var/lib/pgsql            btrfs      subvol=@/var/lib/pgsql 0 0
UUID=c114d95e-bc0a-4b41-a2db-abd21aa9850f /var/log                  btrfs      subvol=@/var/log      0 0
UUID=c114d95e-bc0a-4b41-a2db-abd21aa9850f /var/opt                  btrfs      subvol=@/var/opt      0 0
UUID=c114d95e-bc0a-4b41-a2db-abd21aa9850f /var/spool                btrfs      subvol=@/var/spool    0 0
UUID=c114d95e-bc0a-4b41-a2db-abd21aa9850f /var/tmp                  btrfs      subvol=@/var/tmp      0 0

3: Common Mount Point

No matter what your distribution, You can just add this mount point to your fstab.

#Entry for /dev/sda1 (windows system):
UUID=442456A824569CAC                           /media/System       ntfs-3g     defaults,noauto,locale=en_US.UTF-8      0       0

#Entry for /dev/sda6 (windows data):
UUID=01CF01333AD2FF20                           /media/Docs         ntfs-3g     defaults,locale=en_US.UTF-8             0       0

#Entry for /dev/sda5 (shared partition) :
UUID=954a9b1e-c8c0-4f38-8877-fa891c79c9ae       /media/Works        ext4        defaults,users,exec                     0       2

I mean for every fstab in my system (Fedora, openSUSE, Debian, KaOSx).

mtab

Consider cross check the result with /etc/mtab.

Multiboot: common mtab

4: Custom Mount Point

Now mount point to access other distribution.

Fedora

Still, start with Fedora.

Access: openSUSE, Debian, KaOSx.

#Entry for /dev/sda10 :
#/dev/sda10       /media/KaOSx      xfs         defaults,noauto,users                   0       0
UUID=50f93bc6-711d-4f70-84cf-09748e653543       /media/KaOSx        xfs         defaults,noauto,users                   0       0

#Entry for /dev/sda12 :
UUID=4190d7a9-fb03-4d19-864f-7d04f89c3be0       /media/Debian       ext4        defaults,noauto,users                   0       0

#Entry for /dev/sda9 (openSUSE root):
UUID=c114d95e-bc0a-4b41-a2db-abd21aa9850f       /media/openSUSE     btrfs       defaults,noauto,users                   0       0

#Entry for /dev/sda7 (openSUSE boot):
UUID=23342d48-c3be-402c-b049-b3e9ddeafbc0       /media/Boot         ext4        defaults,noauto,user,errors=remount-ro  0       0

#Entry for /dev/sda8 (openSUSE home):
UUID=0095473d-ae63-4722-8350-f5716e5df333       /media/Fun          xfs         defaults,noauto,users                   0       0

Have a look at the /etc/fstab config for Fedora:

gitlab.com/…/dotfiles/…/fstab.fedora

mtab

Again, consider cross check the result with /etc/mtab.

% cat /etc/mtab | grep sda | column -t
/dev/sda11  /                ext4     rw,relatime,data=ordered                                            0  0
/dev/sda5   /media/Works     ext4     rw,nosuid,nodev,relatime,data=ordered                               0  0
/dev/sda1   /media/System    fuseblk  rw,relatime,user_id=0,group_id=0,allow_other,blksize=4096           0  0
/dev/sda6   /media/Docs      fuseblk  rw,relatime,user_id=0,group_id=0,allow_other,blksize=4096           0  0
/dev/sda12  /media/Debian    ext4     rw,nosuid,nodev,noexec,relatime,data=ordered                        0  0
/dev/sda9   /media/openSUSE  btrfs    rw,nosuid,nodev,noexec,relatime,space_cache,subvolid=257,subvol=/@  0  0
/dev/sda10  /media/KaOSx     xfs      rw,nosuid,nodev,noexec,relatime,attr2,inode64,noquota               0  0
/dev/sda7   /media/Boot      ext4     rw,nosuid,nodev,noexec,relatime,errors=remount-ro,data=ordered      0  0
/dev/sda8   /media/Fun       xfs      rw,nosuid,nodev,noexec,relatime,attr2,inode64,noquota               0  0

Multiboot: custom mtab

Debian

In a same way, we can do the same thing again with Debian.

Access: Fedora, openSUSE, KaOSx.

#Entry for /dev/sda10 :
#/dev/sda10       /media/KaOSx      xfs         defaults,noauto,users                   0       0
UUID=50f93bc6-711d-4f70-84cf-09748e653543       /media/KaOSx        xfs         defaults,noauto,users                   0       0

#Entry for /dev/sda11 :
UUID=9c76fb33-fa7a-46af-b2bb-f82d385b81b6       /media/Fedora       ext4        defaults,noauto,user,errors=remount-ro  0       0

#Entry for /dev/sda9 (openSUSE root):
UUID=c114d95e-bc0a-4b41-a2db-abd21aa9850f       /media/openSUSE     btrfs       defaults,noauto,users                   0       0

#Entry for /dev/sda7 (openSUSE boot):
UUID=23342d48-c3be-402c-b049-b3e9ddeafbc0       /media/Boot         ext4        defaults,noauto,user,errors=remount-ro  0       0

#Entry for /dev/sda8 (openSUSE home):
UUID=0095473d-ae63-4722-8350-f5716e5df333       /media/Fun          xfs         defaults,noauto,users                   0       0

Have a look at the /etc/fstab config for Debian:

gitlab.com/…/dotfiles/…/fstab.debian

KaOSx

And so does KaOSx.

Access: Fedora, openSUSE, Debian.

#Entry for /dev/sda12 :
UUID=4190d7a9-fb03-4d19-864f-7d04f89c3be0       /media/Debian       ext4        defaults,noauto,users                   0       0

#Entry for /dev/sda11 :
UUID=9c76fb33-fa7a-46af-b2bb-f82d385b81b6       /media/Fedora       ext4        defaults,noauto,user,errors=remount-ro  0       0

#Entry for /dev/sda9 (openSUSE root):
UUID=c114d95e-bc0a-4b41-a2db-abd21aa9850f       /media/openSUSE     btrfs       defaults,noauto,users                   0       0

#Entry for /dev/sda7 (openSUSE boot):
UUID=23342d48-c3be-402c-b049-b3e9ddeafbc0       /media/Boot         ext4        defaults,noauto,user,errors=remount-ro  0       0

#Entry for /dev/sda8 (openSUSE home):
UUID=0095473d-ae63-4722-8350-f5716e5df333       /media/Fun          xfs         defaults,noauto,users                   0       0

Have a look at the /etc/fstab config for KaOSx:

gitlab.com/…/dotfiles/…/fstab.kaosx

openSUSE

And also does openSUSE.

Access: Fedora, Debian, KaOSx.

### Other Distribution

#Entry for /dev/sda10 :
#/dev/sda10       /media/KaOSx      xfs         defaults,noauto,users                   0       0
UUID=50f93bc6-711d-4f70-84cf-09748e653543       /media/KaOSx        xfs         defaults,noauto,users                   0       0

#Entry for /dev/sda11 :
UUID=9c76fb33-fa7a-46af-b2bb-f82d385b81b6       /media/Fedora       ext4        defaults,noauto,user,errors=remount-ro  0       0

#Entry for /dev/sda12 :
UUID=4190d7a9-fb03-4d19-864f-7d04f89c3be0       /media/Debian       ext4        defaults,noauto,users                   0       0

Have a look at the /etc/fstab config for openSUSE:

gitlab.com/…/dotfiles/…/fstab.opensuse

GParted

Again with GUI, to have better understanding.

Multiboot: gparted

What’s Next?

Consider continue reading [ Multiboot: chroot ].