Disk usage metrics do not work in specific zone

##### ISSUE TYPE

* Other

##### COMPONENT NAME

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VMWARE
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##### CLOUDSTACK VERSION

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4.18
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##### CONFIGURATION

##### OS / ENVIRONMENT

##### SUMMARY
In my environment, I use 2 zones.

However, in the "x" zone, the metrics part presents a problem when displaying disk and network data.

While in zone "y" all data is shown normally.

Do you have any specific connectivity tests to do?

In principle, the zone settings are identical, the only difference is the following:

Zone X
System VM's -> KVM (The only KVM it has are the two SystemVM)
Zone X environment uses VMware vSphere Client version 6.7.0

Zone y uses the system VM and entire environment with vSphere Client version 7.0.3.01700

##### Remembering that the disk and network metrics just do not appear in the problem area, but the CPU and memory metrics work normally.

Zone X:

Zone Y:

该 issue 未列出任何文件、测试或入口点。首先在两个 zone 中重现 metrics view，并比较 VMware vSphere 6.7.0 和 7.0.3.01700 环境，重点关注为什么磁盘和网络数据缺失，而 CPU 和内存却能显示。完成标准是识别并修复原因，使四种 metric 类型都能在 zone X 中显示。

由索引模型根据 Issue 内容生成。