Compute offering "Custom constrained" not working

[cdfgallo]

ISSUE TYPE

• Bug Report

COMPONENT NAME

Core

CLOUDSTACK VERSION

4.17.0.1 installed on CentOS 7

CONFIGURATION

KVM Hypervisor with compute offering type custom unconstrained

OS / ENVIRONMENT

CentOS 7

SUMMARY

When applying a custom constrained compute offering on a virtual machine on a KVM host it fails to start with error: "internal error: process exited while connecting to monitor: qemu: invalid ram size".
Parameter "memory" in the compute offering is indicated in MB.
There are no issues when applying on the VM a fixed compute offering.

STEPS TO REPRODUCE

Create a VM with a custom constrained compute offering on a KVM host

EXPECTED RESULTS

The VM is created and starts as it happens on previous cloudstack versions.

ACTUAL RESULTS

VM creation fails with error "internal error: process exited while connecting to monitor: qemu: invalid ram size"

[boring-cyborg]

Thanks for opening your first issue here! Be sure to follow the issue template!

[shwstppr]

@cdfgallo I'm not able to reproduce in my lab. Can you please share logs of the complete deploy VM action?
What value of RAM was VM provided?

[cdfgallo]

here attached you can find the log of the vm deploy.
debug.log
I trried as RAM value 1024 or 2048 with same result.

[shwstppr]

@cdfgallo can you try with a template or compute offering which dynamically scalable parameter set to false.
I was able to reproduce this with dynamically scalable enabled for VM with a centos7 host having following config:

# virsh version
Compiled against library: libvirt 4.5.0
Using library: libvirt 4.5.0
Using API: QEMU 4.5.0
Running hypervisor: QEMU 1.5.3

However same thing worked fine with a Ubuntu host with the following config,

# virsh version
Compiled against library: libvirt 8.0.0
Using library: libvirt 8.0.0
Using API: QEMU 8.0.0
Running hypervisor: QEMU 6.2.0

[shwstppr]

@DaanHoogland @GutoVeronezi cc @rohityadavcloud @weizhouapache @nvazquez @harikrishna-patnala VM deployment with following qemu-libvirt config on CentOS7, for a dynamically scalable VM with custom offerings,

# virsh version
Compiled against library: libvirt 4.5.0
Using library: libvirt 4.5.0
Using API: QEMU 4.5.0
Running hypervisor: QEMU 1.5.3

Should this be documented or do we need to add a check in KVM hypervisor code for qemu version? Didn't find any existing documentation for it.

[DaanHoogland]

it is very operator friendly if we do an software check for version on each feature but this will not be very maintainable. I vote documentation.

[shwstppr]

I've created doc PR to address this, apache/cloudstack-documentation#283

@cdfgallo can you please try deploying VM with template and offering that do not have dynamic scaling enabled

[cdfgallo]

@cdfgallo can you please try deploying VM with template and offering that do not have dynamic scaling enabled

@shwstppr sorry but if I apply a fixed compute offering how can it scale dinamically?

[DaanHoogland]

@cdfgallo can you please try deploying VM with template and offering that do not have dynamic scaling enabled

@shwstppr sorry but if I apply a fixed compute offering how can it scale dinamically?

@cdfgallo , I think the message is that you can not if

Compiled against library: libvirt 4.5.0
Using library: libvirt 4.5.0
Using API: QEMU 4.5.0
Running hypervisor: QEMU 1.5.3

but if for instance

# virsh version
Compiled against library: libvirt 8.0.0
Using library: libvirt 8.0.0
Using API: QEMU 8.0.0
Running hypervisor: QEMU 6.2.0

you can.
You´ll have to check your combination.