Re: [Qemu-discuss] Issue related to mounting /dev/nbd0p1

[ramakanth varala]

I don't see any --format..option



address@hidden ~]# qemu-nbd --help
Usage: qemu-nbd [OPTIONS] FILE
QEMU Disk Network Block Device Server

  -p, --port=PORT      port to listen on (default `10809')
  -o, --offset=OFFSET  offset into the image
  -b, --bind=IFACE     interface to bind to (default `0.0.0.0')
  -k, --socket=PATH    path to the unix socket
                       (default '/var/lock/qemu-nbd-DEVICE')
  -r, --read-only      export read-only
  -P, --partition=NUM  only expose partition NUM
  -s, --snapshot       use snapshot file
  -n, --nocache        disable host cache
  -c, --connect=DEV    connect FILE to the local NBD device DEV
  -d, --disconnect     disconnect the specified device
  -e, --shared=NUM     device can be shared by NUM clients (default '1')
  -t, --persistent     don't exit on the last connection
  -v, --verbose        display extra debugging information
  -h, --help           display this help and exit
  -V, --version        output version information and exit

Report bugs to <address@hidden>
address@hidden ~]# qemu-nbd --version
qemu-nbd version 0.0.1
Written by Anthony Liguori.

Copyright (C) 2006 Anthony Liguori <address@hidden>.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.



should i install any other version to get that..?



On Tue, Dec 4, 2018 at 7:14 PM Pascal <address@hidden> wrote:

> disconnect and reconnect with *-f raw* option...
>
> qemu-nbd --connect /dev/nbd0* --format=raw* /home/test/test.3.5.1b.debug/
> test.3.5.1b.debug.raw
>
>
> Le mar. 4 déc. 2018 à 14:32, ramakanth varala <address@hidden>
> a écrit :
>
>> address@hidden ~]# file
>> /home/test/test.3.5.1b.debug/test.3.5.1b.debug.raw
>> /home/test/test.3.5.1b.debug/test.3.5.1b.debug.raw: x86 boot sector;
>> partition 1: ID=0x83, starthead 1, startsector 63, 208782 sectors;
>> partition 2: ID=0x83, starthead 254, startsector 41913585, 16065 sectors,
>> code offset 0x48
>>
>>
>> On Tue, Dec 4, 2018 at 6:48 PM Pascal <address@hidden> wrote:
>>
>>> the partition does not appear and so, cannot be mounted.
>>> moreover, if it appeared, it would have to be formatted before it could
>>> be mounted...
>>>
>>> what is the result of the "file /home/test/test.3.5.1b.debug/
>>> test.3.5.1b.debug.raw" command ?
>>>
>>> Le mar. 4 déc. 2018 à 13:51, ramakanth varala <
>>> address@hidden> a écrit :
>>>
>>>> Hi Pascal..
>>>>
>>>> this works fine ....
>>>>
>>>> address@hidden ~]# qemu-nbd --connect /dev/nbd0
>>>> /home/test/test.3.5.1b.debug/test.3.5.1b.debug.raw
>>>>
>>>> after this when i try to do mount like below...it fails..
>>>>
>>>>
>>>> address@hidden ~]# mount /dev/nbd0p1
>>>> /home/test/test.3.5.1b.debug/mnt/boot/
>>>> mount: special device /dev/nbd0p1 does not exist
>>>>
>>>> but fdisk -l shows me this..
>>>>
>>>>
>>>> address@hidden ~]# fdisk -l /dev/nbd0
>>>>
>>>> Disk /dev/nbd0: 21.4 GB, 21474836480 bytes
>>>> 255 heads, 63 sectors/track, 2610 cylinders
>>>> Units = cylinders of 16065 * 512 = 8225280 bytes
>>>>
>>>>      Device Boot      Start         End      Blocks   Id  System
>>>> /dev/nbd0p1               1          13      104391   83  Linux
>>>> /dev/nbd0p2            2610        2610        8032+  83  Linux
>>>>
>>>>
>>>> Hope we have some way ..which i can mount to partition .
>>>>
>>>> Thanks
>>>> Rama Kanth
>>>>
>>>>
>>>> On Tue, Dec 4, 2018 at 5:07 PM Pascal <address@hidden> wrote:
>>>>
>>>>> # qemu-nbd --connect */dev/nbd0* /home/test/test.3.5.1b.debug/
>>>>> test.3.5.1b.debug.raw
>>>>>
>>>>> Le mar. 4 déc. 2018 à 12:32, ramakanth varala <
>>>>> address@hidden> a écrit :
>>>>>
>>>>>> Hi  Pascal..
>>>>>>
>>>>>> I tried like below..
>>>>>>
>>>>>> address@hidden ~]# qemu-nbd -d /dev/nbd0
>>>>>> /dev/nbd0 disconnected
>>>>>>
>>>>>> address@hidden ~]# qemu-nbd --connect /dev/nbd0p1
>>>>>> /home/test/test.3.5.1b.debug/test.3.5.1b.debug.raw
>>>>>> qemu-nbd: Could not access '/dev/nbd0p1': No such file or directory
>>>>>>
>>>>>>
>>>>>> On Tue, Dec 4, 2018 at 4:55 PM ramakanth varala <
>>>>>> address@hidden> wrote:
>>>>>>
>>>>>>> first time i got below..
>>>>>>>
>>>>>>> address@hidden ~]# kpartx -a /dev/ndb0
>>>>>>> failed to stat() /dev/ndb0
>>>>>>>
>>>>>>> from second time onwards like below..
>>>>>>>
>>>>>>> address@hidden ~]# kpartx -a /dev/nbd0
>>>>>>> device-mapper: resume ioctl failed: Invalid argument
>>>>>>>
>>>>>>>
>>>>>>> On Tue, Dec 4, 2018 at 4:23 PM Jan Schermer <address@hidden> wrote:
>>>>>>>
>>>>>>>> Partigion is missing :-)
>>>>>>>> try:
>>>>>>>> kpartx -a /dev/ndb0
>>>>>>>>
>>>>>>>>
>>>>>>>> > On 4 Dec 2018, at 11:35, ramakanth varala <
>>>>>>>> address@hidden> wrote:
>>>>>>>> >
>>>>>>>> > Hi Pascal..
>>>>>>>> >
>>>>>>>> > yes its RW ...
>>>>>>>> >
>>>>>>>> > address@hidden ~]# fdisk -l /dev/nbd0
>>>>>>>> >
>>>>>>>> > Disk /dev/nbd0: 21.4 GB, 21474836480 bytes
>>>>>>>> > 255 heads, 63 sectors/track, 2610 cylinders
>>>>>>>> > Units = cylinders of 16065 * 512 = 8225280 bytes
>>>>>>>> >
>>>>>>>> >     Device Boot      Start         End      Blocks   Id  System
>>>>>>>> > /dev/nbd0p1               1          13      104391   83  Linux
>>>>>>>> > /dev/nbd0p2            2610        2610        8032+  83  Linux
>>>>>>>> >
>>>>>>>> > address@hidden ~]# ls -ltr /dev/nbd0*
>>>>>>>> > brw-r----- 1 root disk 43, 0 Dec  4 11:06 /dev/nbd0
>>>>>>>> >
>>>>>>>> > address@hidden ~]# mount /dev/nbd0p1
>>>>>>>> /home/test/test.3.5.1b.debug/mnt/boot/
>>>>>>>> > mount: special device /dev/nbd0p1 does not exist
>>>>>>>> >
>>>>>>>> > address@hidden ~]# cat /proc/partitions
>>>>>>>> > major minor  #blocks  name
>>>>>>>> >
>>>>>>>> >   8     0   62914560 sda
>>>>>>>> >   8     1     104391 sda1
>>>>>>>> >   8     2   62806117 sda2
>>>>>>>> > 253     0   56655872 dm-0
>>>>>>>> > 253     1    6127616 dm-1
>>>>>>>> > 253     2     104391 dm-2
>>>>>>>> > 253     3   20860402 dm-3
>>>>>>>> >
>>>>>>>> >
>>>>>>>> > --Not sure..what's missing..
>>>>>>>> >
>>>>>>>> > Thanks
>>>>>>>> > Rama Kanth
>>>>>>>> >
>>>>>>>> > On Tue, Dec 4, 2018 at 3:07 PM Pascal <address@hidden>
>>>>>>>> wrote:
>>>>>>>> >
>>>>>>>> >> hi,
>>>>>>>> >>
>>>>>>>> >> you left fdisk without saving the changes (w before q), so there
>>>>>>>> can't be
>>>>>>>> >> two partitions.
>>>>>>>> >> on the other hand, we should find the existing partition...
>>>>>>>> >> there is a strange warning when fdisk starts: what is on the
>>>>>>>> over side of
>>>>>>>> >> nbd0 ?
>>>>>>>> >> is /dev/nbd0 rw ?
>>>>>>>> >> if you can't re-read the partitions table, can you disconnect
>>>>>>>> /dev/nbd0 and
>>>>>>>> >> then reconnect it ?
>>>>>>>> >>
>>>>>>>> >>
>>>>>>>> >> Le lun. 3 déc. 2018 à 16:17, ramakanth varala <
>>>>>>>> address@hidden>
>>>>>>>> >> a écrit :
>>>>>>>> >>
>>>>>>>> >>> Hi ,
>>>>>>>> >>>
>>>>>>>> >>> I tried below steps .. still with some errors..
>>>>>>>> >>>
>>>>>>>> >>>
>>>>>>>> >>> address@hidden ~]# fdisk /dev/nbd0
>>>>>>>> >>>
>>>>>>>> >>> The number of cylinders for this disk is set to 2610.
>>>>>>>> >>> There is nothing wrong with that, but this is larger than 1024,
>>>>>>>> >>> and could in certain setups cause problems with:
>>>>>>>> >>> 1) software that runs at boot time (e.g., old versions of LILO)
>>>>>>>> >>> 2) booting and partitioning software from other OSs
>>>>>>>> >>>   (e.g., DOS FDISK, OS/2 FDISK)
>>>>>>>> >>>
>>>>>>>> >>> Command (m for help): n
>>>>>>>> >>> Command action
>>>>>>>> >>>   e   extended
>>>>>>>> >>>   p   primary partition (1-4)
>>>>>>>> >>> p
>>>>>>>> >>> Partition number (1-4): 1
>>>>>>>> >>> Partition 1 is already defined.  Delete it before re-adding it.
>>>>>>>> >>>
>>>>>>>> >>> Command (m for help): d
>>>>>>>> >>> Partition number (1-4): 1
>>>>>>>> >>>
>>>>>>>> >>> Command (m for help): d
>>>>>>>> >>> Selected partition 2
>>>>>>>> >>>
>>>>>>>> >>> Command (m for help): p
>>>>>>>> >>>
>>>>>>>> >>> Disk /dev/nbd0: 21.4 GB, 21474836480 bytes
>>>>>>>> >>> 255 heads, 63 sectors/track, 2610 cylinders
>>>>>>>> >>> Units = cylinders of 16065 * 512 = 8225280 bytes
>>>>>>>> >>>
>>>>>>>> >>>     Device Boot      Start         End      Blocks   Id  System
>>>>>>>> >>>
>>>>>>>> >>> Command (m for help): n
>>>>>>>> >>> Command action
>>>>>>>> >>>   e   extended
>>>>>>>> >>>   p   primary partition (1-4)
>>>>>>>> >>> p
>>>>>>>> >>> Partition number (1-4): 1
>>>>>>>> >>> First cylinder (1-2610, default 1):
>>>>>>>> >>> Using default value 1
>>>>>>>> >>> Last cylinder or +size or +sizeM or +sizeK (1-2610, default
>>>>>>>> 2610): 4
>>>>>>>> >>>
>>>>>>>> >>> Command (m for help): n
>>>>>>>> >>> Command action
>>>>>>>> >>>   e   extended
>>>>>>>> >>>   p   primary partition (1-4)
>>>>>>>> >>> p
>>>>>>>> >>> Partition number (1-4): 2
>>>>>>>> >>> First cylinder (5-2610, default 5):
>>>>>>>> >>> Using default value 5
>>>>>>>> >>> Last cylinder or +size or +sizeM or +sizeK (5-2610, default
>>>>>>>> 2610):
>>>>>>>> >>> Using default value 2610
>>>>>>>> >>>
>>>>>>>> >>> Command (m for help): p
>>>>>>>> >>>
>>>>>>>> >>> Disk /dev/nbd0: 21.4 GB, 21474836480 bytes
>>>>>>>> >>> 255 heads, 63 sectors/track, 2610 cylinders
>>>>>>>> >>> Units = cylinders of 16065 * 512 = 8225280 bytes
>>>>>>>> >>>
>>>>>>>> >>>     Device Boot      Start         End      Blocks   Id  System
>>>>>>>> >>> /dev/nbd0p1               1           4       32098+  83  Linux
>>>>>>>> >>> /dev/nbd0p2               5        2610    20932695   83  Linux
>>>>>>>> >>>
>>>>>>>> >>> Command (m for help): q
>>>>>>>> >>>
>>>>>>>> >>> address@hidden ~]# blockdev --rereadpt /dev/nbd0
>>>>>>>> >>> BLKRRPART: Invalid argument
>>>>>>>> >>> address@hidden ~]# ls /dev/nbd0
>>>>>>>> >>> /dev/nbd0
>>>>>>>> >>> address@hidden ~]# ls /dev/nbd0*
>>>>>>>> >>> /dev/nbd0
>>>>>>>> >>>
>>>>>>>> >>>
>>>>>>>> >>>
>>>>>>>> >>> Thanks
>>>>>>>> >>> Rama Kanth
>>>>>>>> >>>
>>>>>>>> >>> On Fri, Nov 30, 2018 at 6:48 PM Pascal <address@hidden>
>>>>>>>> wrote:
>>>>>>>> >>>
>>>>>>>> >>>> do not create nodes manually but with fdisk on nbd0 :
>>>>>>>> >>>>
>>>>>>>> >>>> # fdisk /dev/nbd0
>>>>>>>> >>>> ## now create your partitions in fdisk
>>>>>>>> >>>> ## use w to write changes and q to quit fdisk
>>>>>>>> >>>>
>>>>>>>> >>>> # blocdev --rereadpt /dev/nbd0
>>>>>>>> >>>>
>>>>>>>> >>>> # ls /dev/nbd0*
>>>>>>>> >>>> ## you will now have /dev/nbd0, /dev/nbd0p1 and /dev/nbd0p2
>>>>>>>> >>>>
>>>>>>>> >>>> if this is not the case while the fdisk command ended without
>>>>>>>> error :
>>>>>>>> >>>>
>>>>>>>> >>>> # sync
>>>>>>>> >>>> # qemu-nbd -d /dev/nbd0
>>>>>>>> >>>> # qemu-nbd -c /dev/nbd0 /the/target
>>>>>>>> >>>>
>>>>>>>> >>>>
>>>>>>>> >>>> Le ven. 30 nov. 2018 à 14:04, ramakanth varala <
>>>>>>>> >>>> address@hidden>
>>>>>>>> >>>> a écrit :
>>>>>>>> >>>>
>>>>>>>> >>>>> Hi Pascal & Jakob,
>>>>>>>> >>>>>
>>>>>>>> >>>>> I started from first .
>>>>>>>> >>>>>
>>>>>>>> >>>>> I created manully the partitions as below
>>>>>>>> >>>>>
>>>>>>>> >>>>>   27  mknod /dev/nbd0p1 b 1 4
>>>>>>>> >>>>>   28  mknod /dev/nbd0p2 b 1 4
>>>>>>>> >>>>>
>>>>>>>> >>>>> still in /proc/partitions i don't see any info , it shows as
>>>>>>>> below
>>>>>>>> >>>>>
>>>>>>>> >>>>> address@hidden ~]# cat /proc/partitions
>>>>>>>> >>>>> major minor  #blocks  name
>>>>>>>> >>>>>
>>>>>>>> >>>>>   8     0   62914560 sda
>>>>>>>> >>>>>   8     1     104391 sda1
>>>>>>>> >>>>>   8     2   62806117 sda2
>>>>>>>> >>>>> 253     0   56655872 dm-0
>>>>>>>> >>>>> 253     1    6127616 dm-1
>>>>>>>> >>>>>
>>>>>>>> >>>>> address@hidden ~]# fdisk  -l /dev/nbd0
>>>>>>>> >>>>>
>>>>>>>> >>>>> Disk /dev/nbd0: 21.4 GB, 21474836480 bytes
>>>>>>>> >>>>> 255 heads, 63 sectors/track, 2610 cylinders
>>>>>>>> >>>>> Units = cylinders of 16065 * 512 = 8225280 bytes
>>>>>>>> >>>>>
>>>>>>>> >>>>>     Device Boot      Start         End      Blocks   Id
>>>>>>>> System
>>>>>>>> >>>>> /dev/nbd0p1   *           1          13      104391   83
>>>>>>>> Linux
>>>>>>>> >>>>> /dev/nbd0p2              14        2610    20860402+  8e
>>>>>>>> Linux LVM
>>>>>>>> >>>>>
>>>>>>>> >>>>>
>>>>>>>> >>>>> when i try for mount , i see below error
>>>>>>>> >>>>>
>>>>>>>> >>>>>
>>>>>>>> >>>>> address@hidden ~]# mount /dev/nbd0p1
>>>>>>>> >>>>> /home/test/test.3.5.1b.debug/mnt/boot
>>>>>>>> >>>>> mount: you must specify the filesystem type
>>>>>>>> >>>>>
>>>>>>>> >>>>> i tried to give file system type as below, still issues.
>>>>>>>> >>>>>
>>>>>>>> >>>>> address@hidden ~]# mount -t ext3 /dev/nbd0p1
>>>>>>>> >>>>> /home/test/test.3.5.1b.debug/mnt/boot
>>>>>>>> >>>>> mount: wrong fs type, bad option, bad superblock on
>>>>>>>> /dev/nbd0p1,
>>>>>>>> >>>>>       missing codepage or other error
>>>>>>>> >>>>>       In some cases useful info is found in syslog - try
>>>>>>>> >>>>>       dmesg | tail  or so
>>>>>>>> >>>>>
>>>>>>>> >>>>>
>>>>>>>> >>>>> Any inputs would be really helpfull..
>>>>>>>> >>>>>
>>>>>>>> >>>>>
>>>>>>>> >>>>> Thanks
>>>>>>>> >>>>> Rama Kanth
>>>>>>>> >>>>>
>>>>>>>> >>>>> On Fri, Nov 30, 2018 at 1:50 PM Pascal <address@hidden>
>>>>>>>> wrote:
>>>>>>>> >>>>>
>>>>>>>> >>>>>> restart from zero if possible...
>>>>>>>> >>>>>>
>>>>>>>> >>>>>> # qemu-nbd -d /dev/nbd0
>>>>>>>> >>>>>> # modprobe -rv nbd
>>>>>>>> >>>>>>
>>>>>>>> >>>>>> # modprobe nbd
>>>>>>>> >>>>>> # qemu-nbd -c /dev/nbd0 /the/file
>>>>>>>> >>>>>> # blockdev --rereadpt /dev/nbd0
>>>>>>>> >>>>>> # fdisk -l /dev/nbd0
>>>>>>>> >>>>>> # mount /dev/nbd0p1 /mount/point
>>>>>>>> >>>>>>
>>>>>>>> >>>>>> Le jeu. 29 nov. 2018 à 17:32, Jakob Bohm <
>>>>>>>> address@hidden> a
>>>>>>>> >>>>>> écrit :
>>>>>>>> >>>>>>
>>>>>>>> >>>>>>> Check
>>>>>>>> >>>>>>>
>>>>>>>> >>>>>>>    cat /proc/partitions
>>>>>>>> >>>>>>>
>>>>>>>> >>>>>>> If the partitions are not listed there, the kernel does not
>>>>>>>> >>>>>>> recognize them, perhaps the kernel doesn't recognize that
>>>>>>>> >>>>>>> nbd0 is a "partitionable disk", and thus does not create the
>>>>>>>> >>>>>>> internal nbd0p1 and ndb0p2 devices.
>>>>>>>> >>>>>>>
>>>>>>>> >>>>>>> If the partitions are listed there, you just need to create
>>>>>>>> the
>>>>>>>> >>>>>>> actual /dev/nbd0p1 and /dev/nbd0p2 file names with mknod or
>>>>>>>> >>>>>>> figure out why your "/dev/" management software (maybe udev,
>>>>>>>> >>>>>>> maybe something better) doesn't do that for you.
>>>>>>>> >>>>>>>
>>>>>>>> >>>>>>> On 29/11/2018 12:46, ramakanth varala wrote:
>>>>>>>> >>>>>>>> Still with some errors..
>>>>>>>> >>>>>>>>
>>>>>>>> >>>>>>>> address@hidden ~]# kpartx -a /dev/nbd0
>>>>>>>> >>>>>>>> read error, sector 0
>>>>>>>> >>>>>>>> read error, sector 1
>>>>>>>> >>>>>>>> read error, sector 29
>>>>>>>> >>>>>>>> address@hidden ~]# ls /dev/nbd
>>>>>>>> >>>>>>>> nbd0   nbd1   nbd10  nbd11  nbd12  nbd13  nbd14  nbd15
>>>>>>>> nbd2
>>>>>>>> >> nbd3
>>>>>>>> >>>>>>> nbd4
>>>>>>>> >>>>>>>>  nbd5   nbd6   nbd7   nbd8   nbd9
>>>>>>>> >>>>>>>>
>>>>>>>> >>>>>>>>
>>>>>>>> >>>>>>>>
>>>>>>>> >>>>>>>> On Thu, Nov 29, 2018 at 4:22 PM Nerijus Baliūnas <
>>>>>>>> >>>>>>>> address@hidden> wrote:
>>>>>>>> >>>>>>>>
>>>>>>>> >>>>>>>>> Please try kpartx -a /dev/nbd0
>>>>>>>> >>>>>>>>>
>>>>>>>> >>>>>>>>> 2018-11-29 12:38, ramakanth varala rašė:
>>>>>>>> >>>>>>>>>> thanks for the reply ..
>>>>>>>> >>>>>>>>>>
>>>>>>>> >>>>>>>>>> But i get below error when i do ..
>>>>>>>> >>>>>>>>>>
>>>>>>>> >>>>>>>>>>
>>>>>>>> >>>>>>>>>> address@hidden ~]# partx -a /dev/nbd0
>>>>>>>> >>>>>>>>>> HDIO_GETGEO: Inappropriate ioctl for device
>>>>>>>> >>>>>>>>>>
>>>>>>>> >>>>>>>>>> On Thu, Nov 29, 2018 at 4:04 PM Nerijus Baliūnas <
>>>>>>>> >>>>>>>>>> address@hidden> wrote:
>>>>>>>> >>>>>>>>>>
>>>>>>>> >>>>>>>>>>> 2018-11-29 12:10, ramakanth varala rašė:
>>>>>>>> >>>>>>>>>>>> address@hidden ~]# mount /dev/nbd0p1
>>>>>>>> >>>>>> /home/test.1.3.debug/mnt/boot
>>>>>>>> >>>>>>>>>>>> mount: special device /dev/nbd0p1 does not exist
>>>>>>>> >>>>>>>>>>> partx -a /dev/nbd0
>>>>>>>> >>>>>>>>>>>
>>>>>>>> >>>>>>>
>>>>>>>> >>>>>>>
>>>>>>>> >>>>>>> Enjoy
>>>>>>>> >>>>>>>
>>>>>>>> >>>>>>> Jakob
>>>>>>>> >>>>>>> --
>>>>>>>> >>>>>>> Jakob Bohm, CIO, Partner, WiseMo A/S.
>>>>>>>> https://www.wisemo.com
>>>>>>>> >>>>>>> Transformervej 29, 2860 Søborg, Denmark.  Direct +45 31 13
>>>>>>>> 16 10
>>>>>>>> >>>>>>> This public discussion message is non-binding and may
>>>>>>>> contain
>>>>>>>> >> errors.
>>>>>>>> >>>>>>> WiseMo - Remote Service Management for PCs, Phones and
>>>>>>>> Embedded
>>>>>>>> >>>>>>>
>>>>>>>> >>>>>>>
>>>>>>>> >>>>>>>
>>>>>>>> >>>>>>
>>>>>>>> >>>>>
>>>>>>>> >>>>
>>>>>>>> >>>
>>>>>>>> >>
>>>>>>>>
>>>>>>>>