I/O redirection Guest VM

I/O redirection Guest VM

[Shiva]

Hello,
I am working on building an Storage Intrusion Detection System(SIDS) App 

inside a VM on KVM hypervisor. 

I wanted I/O's from other vm's to first contact this App VM and

 then finally write to the  disk.I went with the network storage as

 an option to achieve this objective. But wanted to know what  about 

I/O's that are not a shared on NFS-share for example? How can 

I intercept these I/O/'s ? As the guest VM will be having its own virtual disk 

and can write to its own partitions that are not part of NFS share.

I know modifying Qemu could be other options here.(Like developing a

 driver or adding redirection of I/O). But I have a time constraint here and

 unlikely to achieve it by this way.

Looking forward to your help/comments.Thanks


--
Shiva

Re: I/O redirection Guest VM

[Fam Zheng]

On Fri, 03/14 04:46, Shiva wrote:
> Hello,
> I am working on building an Storage Intrusion Detection System(SIDS) App 
> 
> inside a VM on KVM hypervisor. 
> 
> I wanted I/O's from other vm's to first contact this App VM and
> 
>  then finally write to the  disk.I went with the network storage as
> 
>  an option to achieve this objective. But wanted to know what  about 
> 
> I/O's that are not a shared on NFS-share for example? How can 
> 
> I intercept these I/O/'s ? As the guest VM will be having its own virtual disk 
> 
> and can write to its own partitions that are not part of NFS share.
> 
> I know modifying Qemu could be other options here.(Like developing a
> 
>  driver or adding redirection of I/O). But I have a time constraint here and
> 
>  unlikely to achieve it by this way.
> 
> Looking forward to your help/comments.Thanks
> 

Not sure I understand it correctly, but this sounds doable to backend.

If you want to intercept the IO's from other VM, can you move the location of
its virtual disk and let them access throught your NFS you App VM can control?

If you only want to observe the IO, you can mirror the writes to a target on
the NFS.

Thanks,
Fam

Re: I/O redirection Guest VM

[Shiva]

Hello Fam,

Thanks a lot  to your reply.

I think I needed to bit more clear in my explanation.

Here is my requirement:

At first,I have a guest vm with its virtual disk performing no storage

intrusion detection  running on top of kvm hypervisor.

Then later I create this new VM app that performs the storage

 intrusion detection functionality again running on top of kvm hypervisor.

I run nfs share inside this vm. Once I do this,I need the I/O's that is 

happening on guest vm to undergo the intrusion detection functionality 

before writes are performed on the disks.  How could I point the image to the 

NFS share if the guest vm prior didn't had this functionality?

And If I do the functionality now,Only NFS-shared partitions could be 

intercepted.What about the other partition writes occurring at the 

guest vm?

Looking forward to your reply. 

--
Shiva

Re: I/O redirection Guest VM

[Fam Zheng]

On Fri, 03/14 02:00, Shivaramakrishnan Vaidyanathan wrote:
> Hello Fam,
> Thanks a lot  to your reply.
> I think I needed to bit more clear in my explanation.
> Here is my requirement:
> At first,I have a guest vm with its virtual disk performing no storage
> intrusion detection  running on top of kvm hypervisor. Then later I create
> this new VM app that performs the storage intrusion detection functionality
> again running on top of kvm hypervisor.I run nfs share inside this vm. Once
> I do this,I need the I/O's that is happening on guest vm to undergo the
> intrusion detection functionality before writes are performed on the disks.
> 
> 
> How could I point the image to the NFS share if the guest vm prior didn't
> had this functionality?
> And If I do the functionality now,Only NFS-shared partitions could be
> intercepted.What about the other partition writes occurring at the guest vm?
> 

Sounds like you need to change the backend of VM on flight to you NFS share.
But I don't think it's supported for now. (Assuming you use QEMU as device
virtualizer).

Fam

Re: I/O redirection Guest VM

[Shiva]

Yes,I am using QEMU as device virtualizer.

Is there any suggestion that you could give to achieve it?

--
Shiva