device manager help..

[pinguim007]

hello folks,

I am trying to install a new hd on my server, but i stuck on the device manager theory.

when I command fdisk -l

appears a series of /dev/dm-0 /dev/dm-1 and etc.

and tells that there is no table partition on /dev/dm-0 etc.


I am trying to create a new lvm partition is an sdb, but the problem is that I don't have the device manager concept.

can somebody explains how it works for me...

thanks anyway.

[Peconet009]

This might help you:
Installing a second hard drive - Debian Wiki

[Exheon]

Have you tried to use gdisk or parted instead?

I ask you cause that output is the kind that you expect when you try look GIUD partition table with fdisk (fdisk will see MBR partition tables only), and servers are expected to use GPT (I don't know if it's your case anyway)

hope to hear from you soon as it would be nice you tell us if you solve your issue.
Good Luck!

[pinguim007]

Have you tried to use gdisk or parted instead?

I ask you cause that output is the kind that you expect when you try look GIUD partition table with fdisk (fdisk will see MBR partition tables only), and servers are expected to use GPT (I don't know if it's your case anyway)

hope to hear from you soon as it would be nice you tell us if you solve your issue.
Good Luck!

hello my friend,

I did everything wich is on the link..
The problem is I receive a message saying that the special device does not exists when I try to mount it....

The others partitions are inside a mapper which I do not known what is it...
/dev/mapper/partition /partition defaults 0 2
I am trying to understand what is this device mapper... I do not want to do things that I don't have the theory...
Do you known something about the device mapper or something about the device manager?

[Exheon]

hello my friend,

I did everything wich is on the link..
The problem is I receive a message saying that the special device does not exists when I try to mount it....

The others partitions are inside a mapper which I do not known what is it...
/dev/mapper/partition /partition defaults 0 2
I am trying to understand what is this device mapper... I do not want to do things that I don't have the theory...
Do you known something about the device mapper or something about the device manager?

It seems that your devices are encrypted with dm_crypt, look, I will try to recreate your situation on a Virtual Machine to see what's going on.

perhaps you remember if you use dm_crypt and/or lvm on your drives? both uses the device mapper infrastructure and it would help a lot to know, if you don't nevermind.

Don't worry, I think we will work this out

[Peconet009]

Here is some more info to get you started:
How to Manage and Use LVM (Logical Volume Management) in Ubuntu - How-To Geek

Disks that are formatted with LVM you will need to format a new disk in the konsol/terminal. Read more from the link above.

[Exheon]

OK, this is what i found so far:

I made a install of Debian, on partitioning I ask the installer to create a encrypted LVM partition table for me, so when the installation process ends and the system boots I'm asked for the given passphrase so i type it and then I can log into my new system, once logged i run the "fdisk -l" command having the same result you provided before.

(If you are asked for the passphrase too, then your partitions are encrypted with dm_crypt too)

Then I halt the Virtual machine, in order to install a second hard disk to it

Then I run "ls /dev" command having this output

block
bsg
bus
cdrom
char
console
core
cpu_dma_latency
debian
disk
dm-0
dm-1
dm-2
dm-3
dm-4
dm-5
dm-6
dri
dvd
fd
full
fuse
hidraw0
hpet
initctl
input
kmsg
log
loop0
loop1
loop2
loop3
loop4
loop5
loop6
loop7
MAKEDEV
mapper
mcelog
mem
net
network_latency
network_throughput
null
port
ppp
psaux
ptmx
pts
random
rfkill
root
rtc
rtc0
scd0
sda
sda1
sda2
sda5
sdb
sg0
sg1
sg2
shm
snapshot
snd
sndstat
sr0
stderr
stdin
stdout
tty
tty0
tty1
tty10
tty11
tty12
tty13
tty14
tty15
tty16
tty17
tty18
tty19
tty2
tty20
tty21
tty22
tty23
tty24
tty25
tty26
tty27
tty28
tty29
tty3
tty30
tty31
tty32
tty33
tty34
tty35
tty36
tty37
tty38
tty39
tty4
tty40
tty41
tty42
tty43
tty44
tty45
tty46
tty47
tty48
tty49
tty5
tty50
tty51
tty52
tty53
tty54
tty55
tty56
tty57
tty58
tty59
tty6
tty60
tty61
tty62
tty63
tty7
tty8
tty9
ttyS0
ttyS1
ttyS2
ttyS3
uinput
urandom
vboxguest
vboxuser
vcs
vcs1
vcs2
vcs3
vcs4
vcs5
vcs6
vcs7
vcsa
vcsa1
vcsa2
vcsa3
vcsa4
vcsa5
vcsa6
vcsa7
vga_arbiter
xconsole
zero

those entries that I marked with 'red'. are the partitions managed by the device mapper , note the "blue" entry now on the ls output, that corresponds to our second hard disk

I'm able to mount it, just by following these steps

First, create a filesystem for it:

mkfs -t ext3 /dev/sdb

(perhaps you would want to set up the partitions with cfdisk or fdisk first instead of creating a filesystem for the whole drive)

then I mounted on /mnt/hd2

mkdir /mnt/hd2
mount /dev/sdb /mnt/hd2

I create a text file on the device mounted on /mnt/hd2 to make sure that correspond of the second disk created for the Debian Virtual Machine, by adding the virtual disk to my Arch Linux VM, and I'm able to mount it and see the file From Arch. so I'm pretty sure this applies to you

Later I will check if I'm able to set LVM for the second disk