Drop Agent dependency on qemu-kvm for Ubuntu

[tetra12]

ISSUE TYPE

• Improvement Request

COMPONENT NAME

Agent, Core

CLOUDSTACK VERSION

4.16.0-Snapshot

CONFIGURATION

Built the latest qemu version from source

OS / ENVIRONMENT

Ubuntu 20.04 and newer

SUMMARY

CS Agent requires qemu-kvm installation. However, newer versions of qemu have dropped dependency on qemu-kvm in favor of qemu-system-x86.

If I build and install the latest qemu from source, I'm unable to install the CloudStack Agent due to its dependency on qemu-kvm, which was dropped in recent releases of qemu.

Thus, I can't use the latest release of qemu, since trying to apt install -y qemu-kvm yields in the following error :

bku@ttx0:~/work/qemu/build$ sudo apt install -y qemu-kvm
Reading package lists... Done
Building dependency tree... Done
Reading state information... Done
Note, selecting 'qemu-system-x86' instead of 'qemu-kvm'
qemu-system-x86 is already the newest version (1:5.2+dfsg-9ubuntu3.1).
qemu-system-x86 set to manually installed.
You might want to run 'apt --fix-broken install' to correct these.
The following packages have unmet dependencies:
 cloudstack-agent : Depends: qemu-kvm (>= 2.5)
                    Depends: ebtables but it is not going to be installed
                    Depends: vlan but it is not going to be installed
                    Depends: ipset but it is not going to be installed
                    Depends: python3-libvirt but it is not going to be installed
                    Depends: ethtool but it is not going to be installed
E: Unmet dependencies. Try 'apt --fix-broken install' with no packages (or specify a solution).

STEPS TO REPRODUCE

1. Clone qemu repository
2. Build and install qemu from master
3. Install a stock libvirt for Ubuntu
3. Validate qemu and virsh installation: `qemu-img --version` , `libvirtd --version`
4. Try to install CloudStack Agent on the node
5. Observe error installing the CS agent

EXPECTED RESULTS

Agent works with the latest qemu and libvirt

ACTUAL RESULTS

Fail to install CS Agent  on the node with the latest `qemu` is installed

[weizhouapache]

@rhtyd @DaanHoogland
do we support non-stock qemu version on hypervisors ?
do we support non-LTS ubuntu versions as hypervisors ? qemu-kvm is not installed in ubuntu 21.04

[tetra12]

That's what ppl say about qemu-kvm here

[DaanHoogland]

@weizhouapache @tetra12 I'm not sure how we can insert this altered dependency but for sure we'll need a separate packaging for newer distributions. If we feel it serves a purpose we should support it, but it will cost us a lot of extra effort to maintain.
Can we use a replace.property to insert the string 'qemu-kvm-x86' in the package?

[weizhouapache]

@weizhouapache @tetra12 I'm not sure how we can insert this altered dependency but for sure we'll need a separate packaging for newer distributions. If we feel it serves a purpose we should support it, but it will cost us a lot of extra effort to maintain.
Can we use a replace.property to insert the string 'qemu-kvm-x86' in the package?

Even if we remove the dependency so cloudstack-agent can be installed, we do not know if it works with the new qemu 5.2, nobody have tested it.
@tetra12 I suggest you to remove your self-build qemu 5.2 and install qemu from official apt repository on ubuntu 20.04, it works fine.

[rohityadavcloud]

On 20.04 I don't see any issue @tetra12, were you testing a recent version of Ubuntu? I would prefer a platform-agnostic depdency otherwise we'll have to keep separate packaging configs for Ubuntu/aarch64 (for ex. RaspberryPi/arm64 platforms).

[weizhouapache]

On 20.04 I don't see any issue @tetra12, were you testing a recent version of Ubuntu? I would prefer a platform-agnostic depdency otherwise we'll have to keep separate packaging configs for Ubuntu/aarch64 (for ex. RaspberryPi/arm64 platforms).

@rhtyd
it looks he built qemu 5.2 from source, which does not have qemu-kvm package any more.

ps:
official qemu version in ubuntu 20.04 is 4.2, which works fine in cloudstack)
official qemu version n ubuntu 21.04 is 5.2, which does not contain qemu-kvm package. it is not LTS.

[tetra12]

@rhtyd @weizhouapache

I need to customize QEMU and built a master from sources, which is 6.1.0-RC4 now.

qemu-kvm package was the wrapper over qemu-kvm-x86 in older 4.x QEMU, which is shipped with Ubuntu 20.04.
QEMU provides it, not OS. It has been removed starting from 5.x and Ubuntu 21.04, which ships 5.2, also doesn't ship qemu-kvm

[weizhouapache]

@tetra12

can you try the following change in debian/control ?

https://github.com/apache/cloudstack/blob/main/debian/control#L25

qemu-kvm (>= 2.5) | qemu-system-x86 (>=5.2)

[tetra12]

@weizhouapache

If you do that change, ACS would fail to install on Ubuntu 18 and 20. Leaving that empty is a generic workaround, that will push users to install correct deps on the host before installing ACS

[weizhouapache]

@weizhouapache

If you do that change, ACS would fail to install on Ubuntu 18 and 20. Leaving that empty is a generic workaround, that will push users to install correct deps on the host before installing ACS

@tetra12
qemu-kvm (>= 2.5) | qemu-system-x86 (>= 5.2) means it is ok if one of qemu-kvm (>= 2.5) and qemu-system-x86 (>= 5.2) is installed.

[gogast]

Issue also exists on Debian 11 .