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According to the Azure documentation, the number of certificates that can be stored in an Azure VM with Windows OS is limited to 199 per availability set. However, it is important to note that properties such as SSH public keys are also pushed as certificates and count towards this limit.
To bypass this limit, you can use the Azure Key Vault extension for Windows or the Azure Key Vault extension for Linux to install certificates. Additionally, with Azure Resource Manager, certificates are stored in the Azure Key Vault. The number of certificates is unlimited for a subscription. There's a 1-MB limit of certificates per deployment, which consists of either a single VM or an availability set.
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