different CPU models in a cluster

[sidereus]

I have servers with different CPU models in a cluster. So, want to create the config file /etc/pve/virtual-guest/cpu-models.conf with common flags for all my CPU. Is there any tool in Proxmox to automate this task? Manually compare flags and create config is a very long and error prone task. Till now I can't create the working config file, because if I just copy flags from lscpu command, it doesn't work, many flags from lscpu qemu doesn't recognize.
My CPUs are:
Intel(R) Xeon(R) CPU E5-2620 v4 @ 2.10GHz
Intel(R) Xeon(R) CPU E5-2620 v3 @ 2.40GHz
If I try to set CPU type to "Haswell", then a VM doesn't want to migrate to the E5-2620 v3 node, saying

2021-05-12 12:03:02 [asr4] kvm: warning: host doesn't support requested feature: CPUID.07H:EBX.hle [bit 4]
2021-05-12 12:03:02 [asr4] kvm: warning: host doesn't support requested feature: CPUID.07H:EBX.rtm [bit 11]
2021-05-12 12:03:02 [asr4] kvm: Host doesn't support requested features

EDIT.
Seems that I found compatible CPU type for both types of my CPUs in the cluster. It's a "Haswell-noTSX".

 

[mira]

You can see a list of recognized CPUID flags by running the following command:

kvm -cpu help

These are the names QEMU recognizes.

 

[ermanishchawla]

Try to use CPU model as "MAX" and see inside VM with lscpu what all flags are visible, do this for all nodes and then put common flags