Xen VM configuration files and VM Persistence

[epretorious]

I have a bit of a quandry: I’ve migrated two PVM’s away from the host system but they persist in Xend even though they are not active on the host; they’re not in XenStore (/var/lib/xenstore/tdb), and; there are no configuration files for the VM’s (in /etc/xen/vm):

[CODE]xen2:~ # ls /etc/xen/vm
sles11-1 sles11-1.xml

xen2:~ # xm list
Name ID Mem VCPUs State Time(s)
Domain-0 0 502 2 r----- 6185.1
oracle1 786 1 15.3
oracle2 786 1 14.0

xen2:~ # xenstore-ls | grep "name = "
name = “Domain-0”
name = “Pool-0”
pool_name = “Pool-0”
name = “Domain-0”[/CODE]

Where is this information being stored?

Eric Pretorious
Truckee, CA

From Chapter 3.1, Creating a Virtual Machine, of the SuSE manual Virtualization with Xen:

The actual configuration file for the Xen guests that is used for the installation is stored at /etc/xen/vm/.

From Chapter 3.5, Deleting Virtual Machines, also of the SuSE manual Virtualization with Xen:

To delete all components of a virtual machine configured with a file-backed virtual disk, you must manually delete… its initial startup file (/etc/xen/vm).

From Chapter 5.3, Configuring a Virtual Machine by Modifying its Xend Settings, also of the SuSE manual Virtualization with Xen:

It is no longer recommended that you edit the initial start-up files stored in /etc/xen/vm, because they are used only during the creation of a new virtual machine.

[epretorious]

@epretorious;12135

Where is this information being stored?

I should also mention that even though…

[LIST]
[]there are no configuration files stored locally (in /etc/xen) and
[]there’s no information stored in XenStore
[/LIST]
…the VM’s can be manually restarted:

[code]xen2:~ # xm list
Name ID Mem VCPUs State Time(s)
Domain-0 0 502 2 r----- 40.1
oracle1 786 1 18.2
oracle2 786 1 16.9

xen2:~ # xm start oracle1

xen2:~ # xm start oracle2

xen2:~ # xm list
Name ID Mem VCPUs State Time(s)
Domain-0 0 502 2 r----- 62.8
oracle1 1 786 1 ------ 10.8
oracle2 2 786 1 r----- 2.8[/code]
So, this begs the question: Where is this information being stored?

[KEVIN1]

epretorious wrote:
[color=blue]

So, this begs the question: Where is this information being stored?[/color]

Your “xm list” reports oracle1 and oracle2. They are not running
therefore they must exist in the XenStore.

To see the configuration of the DomU:

xm list -l oracle1

See here for more information:
https://forums.suse.com/content.php?125-Managing-your-Xen-DomU-Difference-between-xm-new-and-xm-create

–
Kevin Boyle - Knowledge Partner
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[epretorious]

[QUOTE=epretorious;12135]…I’ve migrated two PVM’s away from the host system but they persist in Xend even though they are not active on the host; they’re not in XenStore (/var/lib/xenstore/tdb), and; there are no configuration files for the VM’s (in /etc/xen/vm):

xen2:~ # xenstore-ls | grep "name = " name = "Domain-0" name = "Pool-0" pool_name = "Pool-0" name = "Domain-0"[/QUOTE]

[QUOTE=KBOYLE;12139]Your “xm list” reports oracle1 and oracle2. They are not running therefore they must exist in the XenStore.

To see the configuration of the DomU:

xm list -l oracle1

See here for more information:
https://forums.suse.com/content.php?125-Managing-your-Xen-DomU-Difference-between-xm-new-and-xm-create[/QUOTE]

Thanks for sharing your article “Managing your Xen DomU: Difference between “xm new” and "xm create”, Ken:

However, I’m more confused than before (because now I see that my understanding of Xend & XenStore is not necessarily correct)!

AFAICT, the xenstore-ls command (above) illustrates that the configuration settings of the PVM’s “oracle1” & “oracle2” do not exist in XenStore. However, as you suggested (above) the xm list command contradicts this:

[CODE]xen2:~ # xm list
Name ID Mem VCPUs State Time(s)
Domain-0 0 502 2 r----- 267.9
oracle1 786 1 211.9
oracle2 786 1 22.8

xen2:~ # xenstore-ls | grep oracle

xen2:~ # xm list -l oracle1
(domain
(cpu_weight 256)
(cpu_cap 0)
(pool_name Pool-0)
(bootloader /usr/bin/pygrub)
(vcpus 1)
(cpus (()))
(on_poweroff destroy)
(description ‘’)
(on_crash restart)
(uuid a8422077-d938-3e6b-0f68-9cc83910ad4a)
(bootloader_args ‘’)
(name oracle1)
(on_reboot restart)
(maxmem 786)
(memory 786)
(shadow_memory 0)
(features ‘’)
(on_xend_start ignore)
(on_xend_stop ignore)
…
(device
(vbd
(protocol x86_64-abi)
(uuid 25b28895-67a7-0656-83e8-6a67a677972a)
(bootable 1)
(devid 51712)
(driver paravirtualised)
(dev xvda:disk)
(uname
phy:/dev/disk/by-id/scsi-14945540000000000705f69534353492d73616e325f300000
)
(mode w)
(VDI ‘’)
(backend 0)
)
)
)[/CODE]

And so does this command:

[CODE]xen2:~ # file /var/lib/xenstored/tdb
/var/lib/xenstored/tdb: TDB database version 6, little-endian hash size 7919 bytes

xen2:~ # strings /var/lib/xenstored/tdb | grep oracle
oracle2
oracle1
oracle1BBBl
oracle1
oracle1otocol
oracle1ol
oracle1
oracle1ckend-id
oracle1otocol
oracle1ol
oracle1dT[/CODE]
So I guess that, without any authoritative instructions for the xenstore command, I’m back to Square #1.

Hm.