Libguestfs - Sep 2023 - [EXTERNAL] - Re: LIBGUESTFS mount disk failure

On Sat, Sep 16, 2023 at 03:56:07PM +0000, Teja Konapalli
wrote:
> Hi Richard & Team,
> 
>  
> 
> Could you please help here on the below failure of mounting disk using
> libguestfs.
> 
>  
> 
> OS version: RHEL 8.2
> 
> Libguestfs version: 1.38.0 stable
> 
>  
> 
>  
> 
> Error logs:
> 
>  
> 
> libguestfs: trace: add_drive_ro
"/var/opt/tmp/GRE//RAJA/RAJAT-flat.vmdk"
> libguestfs: trace: add_drive
"/var/opt/tmp/GRE//RAJA/RAJAT-flat.vmdk"
> "readonly:true"
> libguestfs: creating COW overlay to protect original drive content
> libguestfs: trace: disk_create
"/tmp/libguestfsCpl8My/overlay3.qcow2" "qcow2"
> -1 "backingfile:/var/opt/tmp/GRE//RAJA/RAJAT-flat.vmdk"
> libguestfs: command: run: qemu-img
> libguestfs: command: run: \ create
> libguestfs: command: run: \ -f qcow2
> libguestfs: command: run: \ -o backing_file=/var/opt/tmp/GRE//RAJA/
> RAJAT-flat.vmdk
> libguestfs: command: run: \ /tmp/libguestfsCpl8My/overlay3.qcow2
> Formatting '/tmp/libguestfsCpl8My/overlay3.qcow2', fmt=qcow2
size=21474836480
> backing_file=/var/opt/tmp/GRE//RAJA/RAJAT-flat.vmdk cluster_size=65536
> lazy_refcounts=off refcount_bits=16
> libguestfs: trace: disk_create = -1 (error)
^^ There should be an error message between this two lines.  Without
seeing what the error is, it's hard to know what the problem is.

Is this happening in a program you wrote?  If so you probably want to
read the bit about how to handle error messages:

https://libguestfs.org/guestfs.3.html#error-handling

Rich.
> libguestfs: trace: add_drive = -1 (error)
> libguestfs: trace: add_drive_ro = -1 (error)
> libguestfs: trace: close
> libguestfs: closing guestfs handle 0x1e89340 (state 0)
> libguestfs: command: run: rm
> libguestfs: command: run: \ -rf /tmp/libguestfsCpl8My
> 
-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
Read my programming and virtualization blog: http://rwmj.wordpress.com
virt-builder quickly builds VMs from scratch
http://libguestfs.org/virt-builder.1.html

@Raja Ram Sharma
 Can you please help here with the details requested by Rich.

To answer this question Is this happening in a program you wrote?  Yes, we had
written our code to use libguestfs API in c++.

We can have a short call and discuss with you or team, could you please help
with the timings next week Monday or Tuesday.

Thanks
Teja Konapalli


-----Original Message-----
From: Richard W.M. Jones <rjones at redhat.com> 
Sent: Saturday, September 16, 2023 9:39 PM
To: Teja Konapalli <tkonapalli at opentext.com>
Cc: libguestfs at redhat.com; Raja Ram Sharma <rsharma6 at opentext.com>;
Divyanshu Kumar <dkumar3 at opentext.com>
Subject: [EXTERNAL] - Re: LIBGUESTFS mount disk failure

CAUTION: This email originated from outside of the organization. Do not click
links or open attachments unless you recognize the sender and know the content
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On Sat, Sep 16, 2023 at 03:56:07PM +0000, Teja Konapalli
wrote:
> Hi Richard & Team,
>
>
>
> Could you please help here on the below failure of mounting disk using 
> libguestfs.
>
>
>
> OS version: RHEL 8.2
>
> Libguestfs version: 1.38.0 stable
>
>
>
>
>
> Error logs:
>
>
>
> libguestfs: trace: add_drive_ro
"/var/opt/tmp/GRE//RAJA/RAJAT-flat.vmdk"
> libguestfs: trace: add_drive
"/var/opt/tmp/GRE//RAJA/RAJAT-flat.vmdk"
> "readonly:true"
> libguestfs: creating COW overlay to protect original drive content
> libguestfs: trace: disk_create
"/tmp/libguestfsCpl8My/overlay3.qcow2" "qcow2"
> -1 "backingfile:/var/opt/tmp/GRE//RAJA/RAJAT-flat.vmdk"
> libguestfs: command: run: qemu-img
> libguestfs: command: run: \ create
> libguestfs: command: run: \ -f qcow2
> libguestfs: command: run: \ -o backing_file=/var/opt/tmp/GRE//RAJA/
> RAJAT-flat.vmdk
> libguestfs: command: run: \ /tmp/libguestfsCpl8My/overlay3.qcow2
> Formatting '/tmp/libguestfsCpl8My/overlay3.qcow2', fmt=qcow2 
> size=21474836480 backing_file=/var/opt/tmp/GRE//RAJA/RAJAT-flat.vmdk 
> cluster_size=65536 lazy_refcounts=off refcount_bits=16
> libguestfs: trace: disk_create = -1 (error)
^^ There should be an error message between this two lines.  Without seeing what
the error is, it's hard to know what the problem is.

Is this happening in a program you wrote?  If so you probably want to read the
bit about how to handle error messages:

https://urldefense.com/v3/__https://libguestfs.org/guestfs.3.html*error-handling__;Iw!!Obbck6kTJA!a2FcI3CQ6qa1neQWz3uUdjBa4wFqY7ucZ6acLCMnK_P1JEntcQxfaY-P2KOkpYWBt4wXOD0RBiF0T-D7hw$

Rich.
> libguestfs: trace: add_drive = -1 (error)
> libguestfs: trace: add_drive_ro = -1 (error)
> libguestfs: trace: close
> libguestfs: closing guestfs handle 0x1e89340 (state 0)
> libguestfs: command: run: rm
> libguestfs: command: run: \ -rf /tmp/libguestfsCpl8My
>
--
Richard Jones, Virtualization Group, Red Hat
https://urldefense.com/v3/__http://people.redhat.com/*rjones__;fg!!Obbck6kTJA!a2FcI3CQ6qa1neQWz3uUdjBa4wFqY7ucZ6acLCMnK_P1JEntcQxfaY-P2KOkpYWBt4wXOD0RBiH8yx7oyA$
Read my programming and virtualization blog:
https://urldefense.com/v3/__http://rwmj.wordpress.com__;!!Obbck6kTJA!a2FcI3CQ6qa1neQWz3uUdjBa4wFqY7ucZ6acLCMnK_P1JEntcQxfaY-P2KOkpYWBt4wXOD0RBiEeYKbusQ$
virt-builder quickly builds VMs from scratch
https://urldefense.com/v3/__http://libguestfs.org/virt-builder.1.html__;!!Obbck6kTJA!a2FcI3CQ6qa1neQWz3uUdjBa4wFqY7ucZ6acLCMnK_P1JEntcQxfaY-P2KOkpYWBt4wXOD0RBiGXgRfjPQ$

Hi Richard, 

Thank you for the reply, I hope this mail finds you well.

We resolved guestfs_add_drive failure, now guestfs_add_drive is adding disk
successfully after adding "format:raw".

But guestfs_launch is failing Kindly help me to troubleshoot or to find any
workaround.

Error_callback is in-place, it return guestfs_last_error()

guestfs_last_error():
	[ 2023-09-16 17:24:20 ]  errno: ( 10 ) : command: waitpid: No child processes
	[ 2023-09-16 17:24:20 ]  errno: ( 10 ) : command: waitpid: No child processes

While: guestfs_lanch error:
	libguestfs: trace: set_verbose true
	libguestfs: trace: set_verbose = 0
	libguestfs: trace: set_backend "direct"
	libguestfs: trace: set_backend = 0
	libguestfs: create: flags = 0, handle = 0xbb0a70, program = greagent.exe
	libguestfs: trace: add_drive
"/var/opt/omni/tmp/GRE/5029f5c4-e08d-23e1-07d3-96c5c7ffeeac/2023/09/16-3/5029f5c4-e08d-23e1-07d3-96c5c7ffeeac/Datastore2-9166/RAJATEST/RAJATEST_1-flat.vmdk"
"format:raw"
	libguestfs: trace: add_drive = 0
	libguestfs: trace: add_drive
"/var/opt/omni/tmp/GRE/5029f5c4-e08d-23e1-07d3-96c5c7ffeeac/2023/09/16-3/5029f5c4-e08d-23e1-07d3-96c5c7ffeeac/Datastore2-9166/RAJATEST/RAJATEST_2-flat.vmdk"
"format:raw"
	libguestfs: trace: add_drive = 0
	libguestfs: trace: add_drive
"/var/opt/omni/tmp/GRE/5029f5c4-e08d-23e1-07d3-96c5c7ffeeac/2023/09/16-3/5029f5c4-e08d-23e1-07d3-96c5c7ffeeac/Datastore2-9166/RAJATEST/RAJATEST-flat.vmdk"
"format:raw"
	libguestfs: trace: add_drive = 0
	libguestfs: trace: launch
	libguestfs: trace: max_disks
	libguestfs: trace: max_disks = 255
	libguestfs: trace: get_tmpdir
	libguestfs: trace: get_tmpdir = "/tmp"
	libguestfs: trace: version
	libguestfs: trace: version = <struct guestfs_version = major: 1, minor: 38,
release: 4, extra: rhel=8,release=15.module+el8.2.0+5297+222a20af,libvirt, >
	libguestfs: trace: get_backend
	libguestfs: trace: get_backend = "direct"
	libguestfs: launch: program=greagent.exe
	libguestfs: launch:
version=1.38.4rhel=8,release=15.module+el8.2.0+5297+222a20af,libvirt
	libguestfs: launch: backend registered: unix
	libguestfs: launch: backend registered: uml
	libguestfs: launch: backend registered: libvirt
	libguestfs: launch: backend registered: direct
	libguestfs: launch: backend=direct
	libguestfs: launch: tmpdir=/tmp/libguestfsMzD9Rl
	libguestfs: launch: umask=0002
	libguestfs: launch: euid=0
	libguestfs: is_openable: /dev/kvm: No such file or directory
	libguestfs: trace: get_backend_setting "force_tcg"
	libguestfs: trace: get_backend_setting = NULL (error)
	libguestfs: trace: get_cachedir
	libguestfs: trace: get_cachedir = "/var/tmp"
	libguestfs: begin building supermin appliance
	libguestfs: run supermin
	libguestfs: command: run: /usr/bin/supermin
	libguestfs: command: run: \ --build
	libguestfs: command: run: \ --verbose
	libguestfs: command: run: \ --if-newer
	libguestfs: command: run: \ --lock /var/tmp/.guestfs-0/lock
	libguestfs: command: run: \ --copy-kernel
	libguestfs: command: run: \ -f ext2
	libguestfs: command: run: \ --host-cpu x86_64
	libguestfs: command: run: \ /usr/lib64/guestfs/supermin.d
	libguestfs: command: run: \ -o /var/tmp/.guestfs-0/appliance.d
	supermin: version: 5.1.19
	supermin: rpm: detected RPM version 4.14
	supermin: package handler: fedora/rpm
	supermin: acquiring lock on /var/tmp/.guestfs-0/lock
	supermin: if-newer: output does not need rebuilding
	libguestfs: trace: launch = -1 (error)
	libguestfs: trace: close
	libguestfs: closing guestfs handle 0xbb0a70 (state 0)
	libguestfs: command: run: rm
	libguestfs: command: run: \ -rf /tmp/libguestfsMzD9Rl


Thanks
RR




-----Original Message-----
From: Richard W.M. Jones <rjones at redhat.com> 
Sent: Saturday, September 16, 2023 9:39 PM
To: Teja Konapalli <tkonapalli at opentext.com>
Cc: libguestfs at redhat.com; Raja Ram Sharma <rsharma6 at opentext.com>;
Divyanshu Kumar <dkumar3 at opentext.com>
Subject: [EXTERNAL] - Re: LIBGUESTFS mount disk failure

CAUTION: This email originated from outside of the organization. Do not click
links or open attachments unless you recognize the sender and know the content
is safe. If you feel that the email is suspicious, please report it using
PhishAlarm.


On Sat, Sep 16, 2023 at 03:56:07PM +0000, Teja Konapalli
wrote:
> Hi Richard & Team,
>
>
>
> Could you please help here on the below failure of mounting disk using 
> libguestfs.
>
>
>
> OS version: RHEL 8.2
>
> Libguestfs version: 1.38.0 stable
>
>
>
>
>
> Error logs:
>
>
>
> libguestfs: trace: add_drive_ro
"/var/opt/tmp/GRE//RAJA/RAJAT-flat.vmdk"
> libguestfs: trace: add_drive
"/var/opt/tmp/GRE//RAJA/RAJAT-flat.vmdk"
> "readonly:true"
> libguestfs: creating COW overlay to protect original drive content
> libguestfs: trace: disk_create
"/tmp/libguestfsCpl8My/overlay3.qcow2" "qcow2"
> -1 "backingfile:/var/opt/tmp/GRE//RAJA/RAJAT-flat.vmdk"
> libguestfs: command: run: qemu-img
> libguestfs: command: run: \ create
> libguestfs: command: run: \ -f qcow2
> libguestfs: command: run: \ -o backing_file=/var/opt/tmp/GRE//RAJA/
> RAJAT-flat.vmdk
> libguestfs: command: run: \ /tmp/libguestfsCpl8My/overlay3.qcow2
> Formatting '/tmp/libguestfsCpl8My/overlay3.qcow2', fmt=qcow2 
> size=21474836480 backing_file=/var/opt/tmp/GRE//RAJA/RAJAT-flat.vmdk 
> cluster_size=65536 lazy_refcounts=off refcount_bits=16
> libguestfs: trace: disk_create = -1 (error)
^^ There should be an error message between this two lines.  Without seeing what
the error is, it's hard to know what the problem is.

Is this happening in a program you wrote?  If so you probably want to read the
bit about how to handle error messages:

https://urldefense.com/v3/__https://libguestfs.org/guestfs.3.html*error-handling__;Iw!!Obbck6kTJA!cv1KjwDluVdY6QeDtrOh_Pwp78cbFyf3tGQ_N76zq1LTl8f3ml4l1FUbxYL0DYvKOC8zw0dsAbychXT0$

Rich.
> libguestfs: trace: add_drive = -1 (error)
> libguestfs: trace: add_drive_ro = -1 (error)
> libguestfs: trace: close
> libguestfs: closing guestfs handle 0x1e89340 (state 0)
> libguestfs: command: run: rm
> libguestfs: command: run: \ -rf /tmp/libguestfsCpl8My
>
--
Richard Jones, Virtualization Group, Red Hat
https://urldefense.com/v3/__http://people.redhat.com/*rjones__;fg!!Obbck6kTJA!cv1KjwDluVdY6QeDtrOh_Pwp78cbFyf3tGQ_N76zq1LTl8f3ml4l1FUbxYL0DYvKOC8zw0dsAUbGivne$
Read my programming and virtualization blog:
https://urldefense.com/v3/__http://rwmj.wordpress.com__;!!Obbck6kTJA!cv1KjwDluVdY6QeDtrOh_Pwp78cbFyf3tGQ_N76zq1LTl8f3ml4l1FUbxYL0DYvKOC8zw0dsAaDLxRcq$
virt-builder quickly builds VMs from scratch
https://urldefense.com/v3/__http://libguestfs.org/virt-builder.1.html__;!!Obbck6kTJA!cv1KjwDluVdY6QeDtrOh_Pwp78cbFyf3tGQ_N76zq1LTl8f3ml4l1FUbxYL0DYvKOC8zw0dsAWV9JWbZ$

Hi, can you run:

  libguestfs-test-tool

and send us the complete output.

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
Read my programming and virtualization blog: http://rwmj.wordpress.com
Fedora Windows cross-compiler. Compile Windows programs, test, and
build Windows installers. Over 100 libraries supported.
http://fedoraproject.org/wiki/MinGW

Thanks for providing the libguestfs-test-tool output in a previous
message.
> While: guestfs_lanch error:
> 	libguestfs: trace: set_verbose true
> 	libguestfs: trace: set_verbose = 0
> 	libguestfs: trace: set_backend "direct"
> 	libguestfs: trace: set_backend = 0
Here you're setting backend = "direct", and while that isn't
necessarily a problem in itself, the libguestfs-test-tool output that
you provided was for the (normal, for RHEL) libvirt backend.

This could make a difference, so what's the output of:

  $ LIBGUESTFS_BACKEND=direct libguestfs-test-tool

?

By the way, unless you have a specific reason to set
'LIBGUESTFS_BACKEND=direct' that you can articulate, it is best not to
set this as it is less secure and less well tested.  If you just
copied that environment variable from somewhere without understanding
why, then don't do that.

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
Read my programming and virtualization blog: http://rwmj.wordpress.com
Fedora Windows cross-compiler. Compile Windows programs, test, and
build Windows installers. Over 100 libraries supported.
http://fedoraproject.org/wiki/MinGW