You are viewing a plain text version of this content. The canonical link for it is here.
Posted to user@vcl.apache.org by Clifton B Wood <Cl...@MORGAN.EDU> on 2010/07/09 23:30:52 UTC
Question about VCL Cacheing and Image Reloading
I've been testing our VCL setup and I've noticed something in
the logs.
Recently I loaded an image from VCL and it loaded
successfully. According to the logs, after I ended the
reservation, the system proceeded to unregister and reload
that same image to the same host.
I then tried requesting that exact same image. It selected the
same host I used previously. However, rather than quickly
provision the fresh image, it unregistered and reloaded that
exact same image on the exact same VM.
What am I missing here? The image on the VM was just ready for
a quick post setup. Why the full drop and reload routine?
Relevant log entries can be provided if necessary, but I have
to edit them down, first.
Thanks.
- Cliff
Re: Question about VCL Cacheing and Image
Reloading
Posted by Clifton B Wood <Cl...@MORGAN.EDU>.
Aaron,
Thanks for the explanation. That makes a world of sense. Since
we are only dealing with VMware at the moment, I forgot that VCL
did handle other provisioning sources.
- Cliff
Re: Question about VCL Cacheing and Image Reloading
Posted by Aaron Peeler <aa...@ncsu.edu>.
Currentimage.txt is a simple unique identifier used by vcld to determine
what image is loaded on any node, outside of the hypervisor or
provisioning module. Since vcl can use more than one provisioning
source, this identifier needs to exist.
Aaron
On 7/12/10 12:23 AM, Clifton B Wood wrote:
> Of course, now I am a little confused. Why rely on
> currentimage.txt, when VCL queries the hypervisor not much
> later and can get that same information?
>
>
> 2010-07-12 00:07:34|2568|154:157|new|esx.pm:load(208)|VM info
> command: /opt/vcl/bin/apps/vm/vminfo.pl --server 'vmware2' --
> vmname host14 --username vcl --password ##########
> 2010-07-12 00:07:36|2568|154:157|new|esx.pm:load(211)|VM info
> output:
> |2568|154:157|new| Information of Virtual Machine host14
> |2568|154:157|new| Name: host14
> |2568|154:157|new| No. of CPU(s): 1
> |2568|154:157|new| Memory Size: 1024
> |2568|154:157|new| Virtual Disks: 1
> |2568|154:157|new| Template: 0
> |2568|154:157|new| vmPathName: [VCL]
> inuse/host14/vmwareesxmath-base28-v0.vmx
> |2568|154:157|new| Guest OS: Microsoft Windows XP Professional
> (32-bit)
> |2568|154:157|new| guestId: winXPProGuest
> |2568|154:157|new| Host name: vcl-winxp-base.Engineering.soe
> |2568|154:157|new| IP Address: 10.24.60.213
> |2568|154:157|new| VMware Tools: VMware Tools is running and
> the version is current
> |2568|154:157|new| Cpu usage: 12 MHz
> |2568|154:157|new| Host memory usage: 459 MB
> |2568|154:157|new| Guest memory usage: 61 MB
> |2568|154:157|new| Overall Status: The entity is OK
>
> It would see to me that this could be a secondary validation
> as this step happens right before the power-off command is
> issued.
>
> Nevertheless, I will follow your advice and update our images
> to insure the right image name is in currentimage.txt
>
> Thanks.
>
> - Cliff
>
--
Aaron Peeler
Program Manager
Virtual Computing Lab
NC State University
aaron_peeler@ncsu.edu
919-513-4571
Re: Question about VCL Cacheing and Image
Reloading
Posted by Clifton B Wood <Cl...@MORGAN.EDU>.
Of course, now I am a little confused. Why rely on
currentimage.txt, when VCL queries the hypervisor not much
later and can get that same information?
2010-07-12 00:07:34|2568|154:157|new|esx.pm:load(208)|VM info
command: /opt/vcl/bin/apps/vm/vminfo.pl --server 'vmware2' --
vmname host14 --username vcl --password ##########
2010-07-12 00:07:36|2568|154:157|new|esx.pm:load(211)|VM info
output:
|2568|154:157|new| Information of Virtual Machine host14
|2568|154:157|new| Name: host14
|2568|154:157|new| No. of CPU(s): 1
|2568|154:157|new| Memory Size: 1024
|2568|154:157|new| Virtual Disks: 1
|2568|154:157|new| Template: 0
|2568|154:157|new| vmPathName: [VCL]
inuse/host14/vmwareesxmath-base28-v0.vmx
|2568|154:157|new| Guest OS: Microsoft Windows XP Professional
(32-bit)
|2568|154:157|new| guestId: winXPProGuest
|2568|154:157|new| Host name: vcl-winxp-base.Engineering.soe
|2568|154:157|new| IP Address: 10.24.60.213
|2568|154:157|new| VMware Tools: VMware Tools is running and
the version is current
|2568|154:157|new| Cpu usage: 12 MHz
|2568|154:157|new| Host memory usage: 459 MB
|2568|154:157|new| Guest memory usage: 61 MB
|2568|154:157|new| Overall Status: The entity is OK
It would see to me that this could be a secondary validation
as this step happens right before the power-off command is
issued.
Nevertheless, I will follow your advice and update our images
to insure the right image name is in currentimage.txt
Thanks.
- Cliff
Re: Question about VCL Cacheing and Image
Reloading
Posted by Clifton B Wood <Cl...@MORGAN.EDU>.
Ah, that solves a big problem for me. Thank you very much. I
forgot that little step in the derivative images I've made after
provisioning my base.
- Cliff
Re: Question about VCL Cacheing and Image Reloading
Posted by Sean Dilda <se...@duke.edu>.
On 7/9/10 5:30 PM, Clifton B Wood wrote:
> I've been testing our VCL setup and I've noticed something in
> the logs.
>
> Recently I loaded an image from VCL and it loaded
> successfully. According to the logs, after I ended the
> reservation, the system proceeded to unregister and reload
> that same image to the same host.
>
> I then tried requesting that exact same image. It selected the
> same host I used previously. However, rather than quickly
> provision the fresh image, it unregistered and reloaded that
> exact same image on the exact same VM.
>
> What am I missing here? The image on the VM was just ready for
> a quick post setup. Why the full drop and reload routine?
>
> Relevant log entries can be provided if necessary, but I have
> to edit them down, first.
>
Is the currentimage.txt correct in your image? I've noticed that if VCL
loads an image for you, it will not verify the currentimage.txt.
However, if there is an image preloaded (as with your second attempt),
then it will ssh in and check the contents of the file. If it doesn't
match with the image name it expects, it will decide its the wrong image
and reimage the host. If this is the case you should see a log message
indicating that VCL thinks the wrong image is loaded and that is going
to do a reload.