VM console cannot access after VNC certificate expired

##### ISSUE TYPE

* Bug Report

##### COMPONENT NAME

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CPVM
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##### CLOUDSTACK VERSION

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4.18
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##### CONFIGURATION

advanced networking

##### OS / ENVIRONMENT

Hypervisro: KVM virtualization with ubuntu 22.04

##### SUMMARY

VM console cannot access after VNC certificate expired。
Default certificate valid for 1 year ，then automatically renews certificates when they expire by cloudstack。
I made sure the certificate was updated on the host，but Th running VM instances need stop and start to apply the new certificate or migraton to other host. For production environments, this is hard to do

I don't know how to get a new certificate to take effect without rebooting the vm

https://github.com/apache/cloudstack/pull/7015

##### STEPS TO REPRODUCE

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##### EXPECTED RESULTS

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Make a new certificate to take effect without rebooting the vm
Provide a setting to turn off tls for vnc
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##### ACTUAL RESULTS

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先從 issue 中描述的 CPVM 和 VNC 憑證更新流程開始，然後檢視連結的 pull request #7015 和最近的討論。在使用 KVM 和 Ubuntu 22.04 的 CloudStack 4.18 上重現憑證過期的情況；當更新後的憑證能夠套用至正在執行的 VM，且無需停止、啟動或遷移這些 VM 時，即表示完成。

由索引模型根據 Issue 內容生成。